---
_id: '12165'
abstract:
- lang: eng
text: It may come as a surprise that a phenomenon as ubiquitous and prominent as
the transition from laminar to turbulent flow has resisted combined efforts by
physicists, engineers and mathematicians, and remained unresolved for almost one
and a half centuries. In recent years, various studies have proposed analogies
to directed percolation, a well-known universality class in statistical mechanics,
which describes a non-equilibrium phase transition from a fluctuating active phase
into an absorbing state. It is this unlikely relation between the multiscale,
high-dimensional dynamics that signify the transition process in virtually all
flows of practical relevance, and the arguably most basic non-equilibrium phase
transition, that so far has mainly been the subject of model studies, which I
review in this Perspective.
article_processing_charge: No
article_type: original
author:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Hof B. Directed percolation and the transition to turbulence. Nature Reviews
Physics. 2023;5:62-72. doi:10.1038/s42254-022-00539-y
apa: Hof, B. (2023). Directed percolation and the transition to turbulence. Nature
Reviews Physics. Springer Nature. https://doi.org/10.1038/s42254-022-00539-y
chicago: Hof, Björn. “Directed Percolation and the Transition to Turbulence.” Nature
Reviews Physics. Springer Nature, 2023. https://doi.org/10.1038/s42254-022-00539-y.
ieee: B. Hof, “Directed percolation and the transition to turbulence,” Nature
Reviews Physics, vol. 5. Springer Nature, pp. 62–72, 2023.
ista: Hof B. 2023. Directed percolation and the transition to turbulence. Nature
Reviews Physics. 5, 62–72.
mla: Hof, Björn. “Directed Percolation and the Transition to Turbulence.” Nature
Reviews Physics, vol. 5, Springer Nature, 2023, pp. 62–72, doi:10.1038/s42254-022-00539-y.
short: B. Hof, Nature Reviews Physics 5 (2023) 62–72.
date_created: 2023-01-12T12:10:18Z
date_published: 2023-01-01T00:00:00Z
date_updated: 2023-08-01T12:50:48Z
day: '01'
department:
- _id: BjHo
doi: 10.1038/s42254-022-00539-y
external_id:
isi:
- '000890148700002'
intvolume: ' 5'
isi: 1
keyword:
- General Physics and Astronomy
language:
- iso: eng
month: '01'
oa_version: None
page: 62-72
publication: Nature Reviews Physics
publication_identifier:
eissn:
- 2522-5820
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Directed percolation and the transition to turbulence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 5
year: '2023'
...
---
_id: '12105'
abstract:
- lang: eng
text: Data-driven dimensionality reduction methods such as proper orthogonal decomposition
and dynamic mode decomposition have proven to be useful for exploring complex
phenomena within fluid dynamics and beyond. A well-known challenge for these techniques
is posed by the continuous symmetries, e.g. translations and rotations, of the
system under consideration, as drifts in the data dominate the modal expansions
without providing an insight into the dynamics of the problem. In the present
study, we address this issue for fluid flows in rectangular channels by formulating
a continuous symmetry reduction method that eliminates the translations in the
streamwise and spanwise directions simultaneously. We demonstrate our method by
computing the symmetry-reduced dynamic mode decomposition (SRDMD) of sliding windows
of data obtained from the transitional plane-Couette and turbulent plane-Poiseuille
flow simulations. In the former setting, SRDMD captures the dynamics in the vicinity
of the invariant solutions with translation symmetries, i.e. travelling waves
and relative periodic orbits, whereas in the latter, our calculations reveal episodes
of turbulent time evolution that can be approximated by a low-dimensional linear
expansion.
acknowledgement: "E.M. acknowledges funding from the ISTplus fellowship programme.
G.Y. and B.H. acknowledge\r\na grant from the Simons Foundation (662960, BH)."
article_number: A10
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Elena
full_name: Marensi, Elena
id: 0BE7553A-1004-11EA-B805-18983DDC885E
last_name: Marensi
- first_name: Gökhan
full_name: Yalniz, Gökhan
id: 66E74FA2-D8BF-11E9-8249-8DE2E5697425
last_name: Yalniz
orcid: 0000-0002-8490-9312
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
citation:
ama: Marensi E, Yalniz G, Hof B, Budanur NB. Symmetry-reduced dynamic mode decomposition
of near-wall turbulence. Journal of Fluid Mechanics. 2023;954. doi:10.1017/jfm.2022.1001
apa: Marensi, E., Yalniz, G., Hof, B., & Budanur, N. B. (2023). Symmetry-reduced
dynamic mode decomposition of near-wall turbulence. Journal of Fluid Mechanics.
Cambridge University Press. https://doi.org/10.1017/jfm.2022.1001
chicago: Marensi, Elena, Gökhan Yalniz, Björn Hof, and Nazmi B Budanur. “Symmetry-Reduced
Dynamic Mode Decomposition of near-Wall Turbulence.” Journal of Fluid Mechanics.
Cambridge University Press, 2023. https://doi.org/10.1017/jfm.2022.1001.
ieee: E. Marensi, G. Yalniz, B. Hof, and N. B. Budanur, “Symmetry-reduced dynamic
mode decomposition of near-wall turbulence,” Journal of Fluid Mechanics,
vol. 954. Cambridge University Press, 2023.
ista: Marensi E, Yalniz G, Hof B, Budanur NB. 2023. Symmetry-reduced dynamic mode
decomposition of near-wall turbulence. Journal of Fluid Mechanics. 954, A10.
mla: Marensi, Elena, et al. “Symmetry-Reduced Dynamic Mode Decomposition of near-Wall
Turbulence.” Journal of Fluid Mechanics, vol. 954, A10, Cambridge University
Press, 2023, doi:10.1017/jfm.2022.1001.
short: E. Marensi, G. Yalniz, B. Hof, N.B. Budanur, Journal of Fluid Mechanics 954
(2023).
date_created: 2023-01-08T23:00:53Z
date_published: 2023-01-10T00:00:00Z
date_updated: 2023-08-01T12:53:23Z
day: '10'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2022.1001
external_id:
arxiv:
- '2101.07516'
isi:
- '000903336600001'
file:
- access_level: open_access
checksum: 9224f987caefe5dd85a70814d3cce65c
content_type: application/pdf
creator: dernst
date_created: 2023-02-02T12:34:54Z
date_updated: 2023-02-02T12:34:54Z
file_id: '12489'
file_name: 2023_JourFluidMechanics_Marensi.pdf
file_size: 1931647
relation: main_file
success: 1
file_date_updated: 2023-02-02T12:34:54Z
has_accepted_license: '1'
intvolume: ' 954'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '01'
oa: 1
oa_version: Published Version
project:
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
grant_number: '662960'
name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
Studies on Transitional and Turbulent Flows'
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Symmetry-reduced dynamic mode decomposition of near-wall turbulence
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 954
year: '2023'
...
---
_id: '12681'
abstract:
- lang: eng
text: The dissolution of minute concentration of polymers in wall-bounded flows
is well-known for its unparalleled ability to reduce turbulent friction drag.
Another phenomenon, elasto-inertial turbulence (EIT), has been far less studied
even though elastic instabilities have already been observed in dilute polymer
solutions before the discovery of polymer drag reduction. EIT is a chaotic state
driven by polymer dynamics that is observed across many orders of magnitude in
Reynolds number. It involves energy transfer from small elastic scales to large
flow scales. The investigation of the mechanisms of EIT offers the possibility
to better understand other complex phenomena such as elastic turbulence and maximum
drag reduction. In this review, we survey recent research efforts that are advancing
the understanding of the dynamics of EIT. We highlight the fundamental differences
between EIT and Newtonian/inertial turbulence from the perspective of experiments,
numerical simulations, instabilities, and coherent structures. Finally, we discuss
the possible links between EIT and elastic turbulence and polymer drag reduction,
as well as the remaining challenges in unraveling the self-sustaining mechanism
of EIT.
acknowledgement: Part of the material presented here is based upon work supported
by the National Science Foundation CBET (Chemical, Bioengineering, Environmental
and Transport Systems) award 1805636 (to Y.D.), the Binational Science Foundation
award 2016145 (to Y.D. and Victor Steinberg), a FRIA (Fund for Research Training
in Industry and Agriculture) grant of the Belgian F.R.S.-FNRS (National Fund for
Scientific Research) (to V.E.T.), the Marie Curie FP7 Career Integration grant PCIG10-GA-2011-304073
(to V.E.T.), and the Fonds spéciaux pour la recherche grant C-13/19 of the University
of Liege (to V.E.T.). Computational resources have been provided by the Consortium
des Équipements de Calcul Intensif (CECI) funded by the Belgian F.R.S.-FNRS, the
Vermont Advanced Computing Center (VACC), the Partnership for Advanced Computing
in Europe (PRACE), and the Tier-1 supercomputer of the Fédération Wallonie-Bruxelles
funded by the Walloon Region (grant agreement 117545).
article_processing_charge: No
article_type: original
author:
- first_name: Yves
full_name: Dubief, Yves
last_name: Dubief
- first_name: Vincent E.
full_name: Terrapon, Vincent E.
last_name: Terrapon
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Dubief Y, Terrapon VE, Hof B. Elasto-inertial turbulence. Annual Review
of Fluid Mechanics. 2023;55(1):675-705. doi:10.1146/annurev-fluid-032822-025933
apa: Dubief, Y., Terrapon, V. E., & Hof, B. (2023). Elasto-inertial turbulence.
Annual Review of Fluid Mechanics. Annual Reviews. https://doi.org/10.1146/annurev-fluid-032822-025933
chicago: Dubief, Yves, Vincent E. Terrapon, and Björn Hof. “Elasto-Inertial Turbulence.”
Annual Review of Fluid Mechanics. Annual Reviews, 2023. https://doi.org/10.1146/annurev-fluid-032822-025933.
ieee: Y. Dubief, V. E. Terrapon, and B. Hof, “Elasto-inertial turbulence,” Annual
Review of Fluid Mechanics, vol. 55, no. 1. Annual Reviews, pp. 675–705, 2023.
ista: Dubief Y, Terrapon VE, Hof B. 2023. Elasto-inertial turbulence. Annual Review
of Fluid Mechanics. 55(1), 675–705.
mla: Dubief, Yves, et al. “Elasto-Inertial Turbulence.” Annual Review of Fluid
Mechanics, vol. 55, no. 1, Annual Reviews, 2023, pp. 675–705, doi:10.1146/annurev-fluid-032822-025933.
short: Y. Dubief, V.E. Terrapon, B. Hof, Annual Review of Fluid Mechanics 55 (2023)
675–705.
date_created: 2023-02-26T23:01:01Z
date_published: 2023-01-19T00:00:00Z
date_updated: 2023-08-01T13:19:47Z
day: '19'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1146/annurev-fluid-032822-025933
external_id:
isi:
- '000915418100026'
file:
- access_level: open_access
checksum: 2666aa3af2a25252d35eb8681d3edff7
content_type: application/pdf
creator: dernst
date_created: 2023-02-27T09:23:02Z
date_updated: 2023-02-27T09:23:02Z
file_id: '12690'
file_name: 2023_AnnReviewFluidMech_Dubief.pdf
file_size: 4036706
relation: main_file
success: 1
file_date_updated: 2023-02-27T09:23:02Z
has_accepted_license: '1'
intvolume: ' 55'
isi: 1
issue: '1'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: 675-705
publication: Annual Review of Fluid Mechanics
publication_identifier:
eissn:
- 1545-4479
issn:
- 0066-4189
publication_status: published
publisher: Annual Reviews
quality_controlled: '1'
scopus_import: '1'
status: public
title: Elasto-inertial turbulence
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 55
year: '2023'
...
---
_id: '12682'
abstract:
- lang: eng
text: 'Since the seminal studies by Osborne Reynolds in the nineteenth century,
pipe flow has served as a primary prototype for investigating the transition to
turbulence in wall-bounded flows. Despite the apparent simplicity of this flow,
various facets of this problem have occupied researchers for more than a century.
Here we review insights from three distinct perspectives: (a) stability and susceptibility
of laminar flow, (b) phase transition and spatiotemporal dynamics, and (c) dynamical
systems analysis of the Navier—Stokes equations. We show how these perspectives
have led to a profound understanding of the onset of turbulence in pipe flow.
Outstanding open points, applications to flows of complex fluids, and similarities
with other wall-bounded flows are discussed.'
acknowledgement: 'The authors are very grateful to Laurette Tuckerman for her helpful
comments. This work was supported by grants from the Simons Foundation (grant numbers
662985, D.B., and 662960, B.H.) and the Priority Programme “SPP 1881: Turbulent
Superstructures” of the Deutsche Forschungsgemeinschaft (grant number AV120/3-2
to M.A.).'
article_processing_charge: No
article_type: original
author:
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
- first_name: Dwight
full_name: Barkley, Dwight
last_name: Barkley
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Avila M, Barkley D, Hof B. Transition to turbulence in pipe flow. Annual
Review of Fluid Mechanics. 2023;55:575-602. doi:10.1146/annurev-fluid-120720-025957
apa: Avila, M., Barkley, D., & Hof, B. (2023). Transition to turbulence in pipe
flow. Annual Review of Fluid Mechanics. Annual Reviews. https://doi.org/10.1146/annurev-fluid-120720-025957
chicago: Avila, Marc, Dwight Barkley, and Björn Hof. “Transition to Turbulence in
Pipe Flow.” Annual Review of Fluid Mechanics. Annual Reviews, 2023. https://doi.org/10.1146/annurev-fluid-120720-025957.
ieee: M. Avila, D. Barkley, and B. Hof, “Transition to turbulence in pipe flow,”
Annual Review of Fluid Mechanics, vol. 55. Annual Reviews, pp. 575–602,
2023.
ista: Avila M, Barkley D, Hof B. 2023. Transition to turbulence in pipe flow. Annual
Review of Fluid Mechanics. 55, 575–602.
mla: Avila, Marc, et al. “Transition to Turbulence in Pipe Flow.” Annual Review
of Fluid Mechanics, vol. 55, Annual Reviews, 2023, pp. 575–602, doi:10.1146/annurev-fluid-120720-025957.
short: M. Avila, D. Barkley, B. Hof, Annual Review of Fluid Mechanics 55 (2023)
575–602.
date_created: 2023-02-26T23:01:01Z
date_published: 2023-01-19T00:00:00Z
date_updated: 2023-08-01T13:20:30Z
day: '19'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1146/annurev-fluid-120720-025957
external_id:
isi:
- '000915418100023'
file:
- access_level: open_access
checksum: f99ef30f76cabc9e5e1946b380c16db4
content_type: application/pdf
creator: dernst
date_created: 2023-02-27T09:35:52Z
date_updated: 2023-02-27T09:35:52Z
file_id: '12691'
file_name: 2023_AnnReviewFluidMech_Avila.pdf
file_size: 4769537
relation: main_file
success: 1
file_date_updated: 2023-02-27T09:35:52Z
has_accepted_license: '1'
intvolume: ' 55'
isi: 1
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
page: 575-602
project:
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
grant_number: '662960'
name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
Studies on Transitional and Turbulent Flows'
publication: Annual Review of Fluid Mechanics
publication_identifier:
issn:
- 0066-4189
publication_status: published
publisher: Annual Reviews
quality_controlled: '1'
scopus_import: '1'
status: public
title: Transition to turbulence in pipe flow
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 55
year: '2023'
...
---
_id: '12172'
abstract:
- lang: eng
text: In industrial reactors and equipment, non-ideality is quite a common phenomenon
rather than an exception. These deviations from ideality impact the process's
overall efficiency and the effectiveness of the equipment. To recognize the associated
non-ideality, one needs to have enough understanding of the formulation of the
equations and in-depth knowledge of the residence time distribution (RTD) data
of real reactors. In the current work, step input and pulse input were used to
create RTD data for Cascade continuous stirred tank reactors (CSTRs). For the
aforementioned configuration, experiments were run at various flow rates to validate
the developed characteristic equations. To produce RTD data, distilled water was
utilized as the flowing fluid, and NaOH was the tracer substance. The ideal behavior
of tracer concentration exits age distribution, and cumulative fraction for each
setup and each input was plotted and experimental results were compared with perfect
behavior. Deviation of concentration exit age distribution and cumulative fractional
distribution from ideal behavior is more in pulse input as compared to a step
input. For ideal cases, the exit age distribution curve and cumulative fraction
curves are independent of the type of input. But a significant difference was
observed for the two cases, which may be due to non-measurable fluctuations in
volumetric flow rate, non-achievement of instant injection of tracer in case of
pulse input, and slight variations in the sampling period. Further, with increasing
flow rate, concentration, exit age, and cumulative fractional curves shifted upward,
and this behavior matches with the actual case.
article_processing_charge: No
article_type: original
author:
- first_name: Bushra
full_name: Khatoon, Bushra
last_name: Khatoon
- first_name: Shoaib
full_name: Kamil, Shoaib
id: 185a19af-dc7d-11ea-9b2f-8eb2201959e9
last_name: Kamil
- first_name: Hitesh
full_name: Babu, Hitesh
last_name: Babu
- first_name: M.
full_name: Siraj Alam, M.
last_name: Siraj Alam
citation:
ama: 'Khatoon B, Kamil S, Babu H, Siraj Alam M. Experimental analysis of Cascade
CSTRs with step and pulse inputs. Materials Today: Proceedings. 2023;78(Part
1):40-47. doi:10.1016/j.matpr.2022.11.037'
apa: 'Khatoon, B., Kamil, S., Babu, H., & Siraj Alam, M. (2023). Experimental
analysis of Cascade CSTRs with step and pulse inputs. Materials Today: Proceedings.
Elsevier. https://doi.org/10.1016/j.matpr.2022.11.037'
chicago: 'Khatoon, Bushra, Shoaib Kamil, Hitesh Babu, and M. Siraj Alam. “Experimental
Analysis of Cascade CSTRs with Step and Pulse Inputs.” Materials Today: Proceedings.
Elsevier, 2023. https://doi.org/10.1016/j.matpr.2022.11.037.'
ieee: 'B. Khatoon, S. Kamil, H. Babu, and M. Siraj Alam, “Experimental analysis
of Cascade CSTRs with step and pulse inputs,” Materials Today: Proceedings,
vol. 78, no. Part 1. Elsevier, pp. 40–47, 2023.'
ista: 'Khatoon B, Kamil S, Babu H, Siraj Alam M. 2023. Experimental analysis of
Cascade CSTRs with step and pulse inputs. Materials Today: Proceedings. 78(Part
1), 40–47.'
mla: 'Khatoon, Bushra, et al. “Experimental Analysis of Cascade CSTRs with Step
and Pulse Inputs.” Materials Today: Proceedings, vol. 78, no. Part 1, Elsevier,
2023, pp. 40–47, doi:10.1016/j.matpr.2022.11.037.'
short: 'B. Khatoon, S. Kamil, H. Babu, M. Siraj Alam, Materials Today: Proceedings
78 (2023) 40–47.'
date_created: 2023-01-12T12:11:26Z
date_published: 2023-03-20T00:00:00Z
date_updated: 2023-08-16T09:08:11Z
day: '20'
department:
- _id: BjHo
doi: 10.1016/j.matpr.2022.11.037
intvolume: ' 78'
issue: Part 1
keyword:
- General Medicine
language:
- iso: eng
month: '03'
oa_version: None
page: 40-47
publication: 'Materials Today: Proceedings'
publication_identifier:
issn:
- 2214-7853
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Experimental analysis of Cascade CSTRs with step and pulse inputs
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 78
year: '2023'
...
---
_id: '14341'
abstract:
- lang: eng
text: Flows through pipes and channels are, in practice, almost always turbulent,
and the multiscale eddying motion is responsible for a major part of the encountered
friction losses and pumping costs1. Conversely, for pulsatile flows, in particular
for aortic blood flow, turbulence levels remain low despite relatively large peak
velocities. For aortic blood flow, high turbulence levels are intolerable as they
would damage the shear-sensitive endothelial cell layer2,3,4,5. Here we show that
turbulence in ordinary pipe flow is diminished if the flow is driven in a pulsatile
mode that incorporates all the key features of the cardiac waveform. At Reynolds
numbers comparable to those of aortic blood flow, turbulence is largely inhibited,
whereas at much higher speeds, the turbulent drag is reduced by more than 25%.
This specific operation mode is more efficient when compared with steady driving,
which is the present situation for virtually all fluid transport processes ranging
from heating circuits to water, gas and oil pipelines.
acknowledged_ssus:
- _id: M-Shop
- _id: ScienComp
acknowledgement: We acknowledge the assistance of the Miba machine shop and the team
of the ISTA-HPC cluster. We thank M. Quadrio for the discussions. The work was supported
by the Simons Foundation (grant no. 662960) and by the Austrian Science Fund (grant
no. I4188-N30), within Deutsche Forschungsgemeinschaft research unit FOR 2688.
article_processing_charge: No
article_type: original
author:
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Scarselli D, Lopez Alonso JM, Varshney A, Hof B. Turbulence suppression by
cardiac-cycle-inspired driving of pipe flow. Nature. 2023;621(7977):71-74.
doi:10.1038/s41586-023-06399-5
apa: Scarselli, D., Lopez Alonso, J. M., Varshney, A., & Hof, B. (2023). Turbulence
suppression by cardiac-cycle-inspired driving of pipe flow. Nature. Springer
Nature. https://doi.org/10.1038/s41586-023-06399-5
chicago: Scarselli, Davide, Jose M Lopez Alonso, Atul Varshney, and Björn Hof. “Turbulence
Suppression by Cardiac-Cycle-Inspired Driving of Pipe Flow.” Nature. Springer
Nature, 2023. https://doi.org/10.1038/s41586-023-06399-5.
ieee: D. Scarselli, J. M. Lopez Alonso, A. Varshney, and B. Hof, “Turbulence suppression
by cardiac-cycle-inspired driving of pipe flow,” Nature, vol. 621, no.
7977. Springer Nature, pp. 71–74, 2023.
ista: Scarselli D, Lopez Alonso JM, Varshney A, Hof B. 2023. Turbulence suppression
by cardiac-cycle-inspired driving of pipe flow. Nature. 621(7977), 71–74.
mla: Scarselli, Davide, et al. “Turbulence Suppression by Cardiac-Cycle-Inspired
Driving of Pipe Flow.” Nature, vol. 621, no. 7977, Springer Nature, 2023,
pp. 71–74, doi:10.1038/s41586-023-06399-5.
short: D. Scarselli, J.M. Lopez Alonso, A. Varshney, B. Hof, Nature 621 (2023) 71–74.
date_created: 2023-09-17T22:01:09Z
date_published: 2023-09-07T00:00:00Z
date_updated: 2023-09-20T12:10:22Z
day: '07'
department:
- _id: BjHo
doi: 10.1038/s41586-023-06399-5
external_id:
pmid:
- '37673988'
intvolume: ' 621'
issue: '7977'
language:
- iso: eng
month: '09'
oa_version: None
page: 71-74
pmid: 1
project:
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
grant_number: '662960'
name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
Studies on Transitional and Turbulent Flows'
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
call_identifier: FWF
grant_number: I04188
name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
publication: Nature
publication_identifier:
eissn:
- 1476-4687
issn:
- 0028-0836
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
link:
- description: News on ISTA website
relation: press_release
url: https://www.ista.ac.at/en/news/pumping-like-the-heart/
scopus_import: '1'
status: public
title: Turbulence suppression by cardiac-cycle-inspired driving of pipe flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 621
year: '2023'
...
---
_id: '12726'
abstract:
- lang: eng
text: "Most motions of many-body systems at any scale in nature with sufficient
degrees\r\nof freedom tend to be chaotic; reaching from the orbital motion of
planets, the air\r\ncurrents in our atmosphere, down to the water flowing through
our pipelines or\r\nthe movement of a population of bacteria. To the observer
it is therefore intriguing\r\nwhen a moving collective exhibits order. Collective
motion of flocks of birds, schools\r\nof fish or swarms of self-propelled particles
or robots have been studied extensively\r\nover the past decades but the mechanisms
involved in the transition from chaos to\r\norder remain unclear. Here, the interactions,
that in most systems give rise to chaos,\r\nsustain order. In this thesis we investigate
mechanisms that preserve, destabilize\r\nor lead to the ordered state. We show
that endothelial cells migrating in circular\r\nconfinements transition to a collective
rotating state and concomitantly synchronize\r\nthe frequencies of nucleating
actin waves within individual cells. Consequently,\r\nthe frequency dependent
cell migration speed uniformizes across the population.\r\nComplementary to the
WAVE dependent nucleation of traveling actin waves, we\r\nshow that in leukocytes
the actin polymerization depending on WASp generates\r\npushing forces locally
at stationary patches. Next, in pipe flows, we study methods\r\nto disrupt the
self–sustaining cycle of turbulence and therefore relaminarize the\r\nflow. While
we find in pulsating flow conditions that turbulence emerges through a\r\nhelical
instability during the decelerating phase. Finally, we show quantitatively in\r\nbrain
slices of mice that wild-type control neurons can compensate the migratory\r\ndeficits
of a genetically modified neuronal sub–population in the developing cortex."
acknowledged_ssus:
- _id: M-Shop
- _id: Bio
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Michael
full_name: Riedl, Michael
id: 3BE60946-F248-11E8-B48F-1D18A9856A87
last_name: Riedl
orcid: 0000-0003-4844-6311
citation:
ama: Riedl M. Synchronization in collectively moving active matter. 2023. doi:10.15479/at:ista:12726
apa: Riedl, M. (2023). Synchronization in collectively moving active matter.
Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12726
chicago: Riedl, Michael. “Synchronization in Collectively Moving Active Matter.”
Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12726.
ieee: M. Riedl, “Synchronization in collectively moving active matter,” Institute
of Science and Technology Austria, 2023.
ista: Riedl M. 2023. Synchronization in collectively moving active matter. Institute
of Science and Technology Austria.
mla: Riedl, Michael. Synchronization in Collectively Moving Active Matter.
Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12726.
short: M. Riedl, Synchronization in Collectively Moving Active Matter, Institute
of Science and Technology Austria, 2023.
date_created: 2023-03-15T13:22:13Z
date_published: 2023-03-23T00:00:00Z
date_updated: 2023-11-30T10:55:13Z
day: '23'
ddc:
- '530'
degree_awarded: PhD
department:
- _id: GradSch
- _id: BjHo
doi: 10.15479/at:ista:12726
file:
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checksum: eba0e19fe57a8c15e7aeab55a845efb7
content_type: application/pdf
creator: cchlebak
date_created: 2023-03-23T12:49:23Z
date_updated: 2023-11-24T11:57:46Z
description: the main file is missing the bibliography. See new thesis record 14530
for updated files.
file_id: '12745'
file_name: Thesis_Riedl_2023.pdf
file_size: 63734746
relation: main_file
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content_type: application/octet-stream
creator: cchlebak
date_created: 2023-03-23T12:54:34Z
date_updated: 2023-09-24T22:30:03Z
embargo_to: open_access
file_id: '12746'
file_name: Thesis_Riedl_2023_source.rar
file_size: 339473651
relation: source_file
file_date_updated: 2023-11-24T11:57:46Z
has_accepted_license: '1'
language:
- iso: eng
month: '03'
oa_version: None
page: '260'
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '10703'
relation: part_of_dissertation
status: public
- id: '10791'
relation: part_of_dissertation
status: public
- id: '7932'
relation: part_of_dissertation
status: public
- id: '461'
relation: part_of_dissertation
status: public
- id: '14530'
relation: new_edition
status: public
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: Synchronization in collectively moving active matter
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2023'
...
---
_id: '13274'
abstract:
- lang: eng
text: Viscous flows through pipes and channels are steady and ordered until, with
increasing velocity, the laminar motion catastrophically breaks down and gives
way to turbulence. How this apparently discontinuous change from low- to high-dimensional
motion can be rationalized within the framework of the Navier-Stokes equations
is not well understood. Exploiting geometrical properties of transitional channel
flow we trace turbulence to far lower Reynolds numbers (Re) than previously possible
and identify the complete path that reversibly links fully turbulent motion to
an invariant solution. This precursor of turbulence destabilizes rapidly with
Re, and the accompanying explosive increase in attractor dimension effectively
marks the transition between deterministic and de facto stochastic dynamics.
acknowledgement: We thank Baofang Song as well as the developers of Channelflow for
sharing their numerical codes, and Mukund Vasudevan and Holger Kantz for fruitful
discussions. This work was supported by a grant from the Simons Foundation (662960,
B. H.).
article_number: '034002'
article_processing_charge: No
article_type: original
author:
- first_name: Chaitanya S
full_name: Paranjape, Chaitanya S
id: 3D85B7C4-F248-11E8-B48F-1D18A9856A87
last_name: Paranjape
- first_name: Gökhan
full_name: Yalniz, Gökhan
id: 66E74FA2-D8BF-11E9-8249-8DE2E5697425
last_name: Yalniz
orcid: 0000-0002-8490-9312
- first_name: Yohann
full_name: Duguet, Yohann
last_name: Duguet
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Paranjape CS, Yalniz G, Duguet Y, Budanur NB, Hof B. Direct path from turbulence
to time-periodic solutions. Physical Review Letters. 2023;131(3). doi:10.1103/physrevlett.131.034002
apa: Paranjape, C. S., Yalniz, G., Duguet, Y., Budanur, N. B., & Hof, B. (2023).
Direct path from turbulence to time-periodic solutions. Physical Review Letters.
American Physical Society. https://doi.org/10.1103/physrevlett.131.034002
chicago: Paranjape, Chaitanya S, Gökhan Yalniz, Yohann Duguet, Nazmi B Budanur,
and Björn Hof. “Direct Path from Turbulence to Time-Periodic Solutions.” Physical
Review Letters. American Physical Society, 2023. https://doi.org/10.1103/physrevlett.131.034002.
ieee: C. S. Paranjape, G. Yalniz, Y. Duguet, N. B. Budanur, and B. Hof, “Direct
path from turbulence to time-periodic solutions,” Physical Review Letters,
vol. 131, no. 3. American Physical Society, 2023.
ista: Paranjape CS, Yalniz G, Duguet Y, Budanur NB, Hof B. 2023. Direct path from
turbulence to time-periodic solutions. Physical Review Letters. 131(3), 034002.
mla: Paranjape, Chaitanya S., et al. “Direct Path from Turbulence to Time-Periodic
Solutions.” Physical Review Letters, vol. 131, no. 3, 034002, American
Physical Society, 2023, doi:10.1103/physrevlett.131.034002.
short: C.S. Paranjape, G. Yalniz, Y. Duguet, N.B. Budanur, B. Hof, Physical Review
Letters 131 (2023).
date_created: 2023-07-24T09:43:59Z
date_published: 2023-07-21T00:00:00Z
date_updated: 2023-12-13T11:40:19Z
day: '21'
department:
- _id: GradSch
- _id: BjHo
doi: 10.1103/physrevlett.131.034002
external_id:
arxiv:
- '2306.05098'
isi:
- '001052929900004'
intvolume: ' 131'
isi: 1
issue: '3'
keyword:
- General Physics and Astronomy
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.48550/arXiv.2306.05098
month: '07'
oa: 1
oa_version: Preprint
project:
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
grant_number: '662960'
name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
Studies on Transitional and Turbulent Flows'
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Direct path from turbulence to time-periodic solutions
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 131
year: '2023'
...
---
_id: '14361'
abstract:
- lang: eng
text: Whether one considers swarming insects, flocking birds, or bacterial colonies,
collective motion arises from the coordination of individuals and entails the
adjustment of their respective velocities. In particular, in close confinements,
such as those encountered by dense cell populations during development or regeneration,
collective migration can only arise coordinately. Yet, how individuals unify their
velocities is often not understood. Focusing on a finite number of cells in circular
confinements, we identify waves of polymerizing actin that function as a pacemaker
governing the speed of individual cells. We show that the onset of collective
motion coincides with the synchronization of the wave nucleation frequencies across
the population. Employing a simpler and more readily accessible mechanical model
system of active spheres, we identify the synchronization of the individuals’
internal oscillators as one of the essential requirements to reach the corresponding
collective state. The mechanical ‘toy’ experiment illustrates that the global
synchronous state is achieved by nearest neighbor coupling. We suggest by analogy
that local coupling and the synchronization of actin waves are essential for the
emergent, self-organized motion of cell collectives.
acknowledged_ssus:
- _id: Bio
- _id: LifeSc
- _id: M-Shop
acknowledgement: We thank K. O’Keeffe, E. Hannezo, P. Devreotes, C. Dessalles, and
E. Martens for discussion and/or critical reading of the manuscript; the Bioimaging
Facility of ISTA for excellent support, as well as the Life Science Facility and
the Miba Machine Shop of ISTA. This work was supported by the European Research
Council (ERC StG 281556 and CoG 724373) to M.S.
article_number: '5633'
article_processing_charge: Yes
article_type: original
author:
- first_name: Michael
full_name: Riedl, Michael
id: 3BE60946-F248-11E8-B48F-1D18A9856A87
last_name: Riedl
orcid: 0000-0003-4844-6311
- first_name: Isabelle D
full_name: Mayer, Isabelle D
id: 61763940-15b2-11ec-abd3-cfaddfbc66b4
last_name: Mayer
- first_name: Jack
full_name: Merrin, Jack
id: 4515C308-F248-11E8-B48F-1D18A9856A87
last_name: Merrin
orcid: 0000-0001-5145-4609
- first_name: Michael K
full_name: Sixt, Michael K
id: 41E9FBEA-F248-11E8-B48F-1D18A9856A87
last_name: Sixt
orcid: 0000-0002-6620-9179
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Riedl M, Mayer ID, Merrin J, Sixt MK, Hof B. Synchronization in collectively
moving inanimate and living active matter. Nature Communications. 2023;14.
doi:10.1038/s41467-023-41432-1
apa: Riedl, M., Mayer, I. D., Merrin, J., Sixt, M. K., & Hof, B. (2023). Synchronization
in collectively moving inanimate and living active matter. Nature Communications.
Springer Nature. https://doi.org/10.1038/s41467-023-41432-1
chicago: Riedl, Michael, Isabelle D Mayer, Jack Merrin, Michael K Sixt, and Björn
Hof. “Synchronization in Collectively Moving Inanimate and Living Active Matter.”
Nature Communications. Springer Nature, 2023. https://doi.org/10.1038/s41467-023-41432-1.
ieee: M. Riedl, I. D. Mayer, J. Merrin, M. K. Sixt, and B. Hof, “Synchronization
in collectively moving inanimate and living active matter,” Nature Communications,
vol. 14. Springer Nature, 2023.
ista: Riedl M, Mayer ID, Merrin J, Sixt MK, Hof B. 2023. Synchronization in collectively
moving inanimate and living active matter. Nature Communications. 14, 5633.
mla: Riedl, Michael, et al. “Synchronization in Collectively Moving Inanimate and
Living Active Matter.” Nature Communications, vol. 14, 5633, Springer Nature,
2023, doi:10.1038/s41467-023-41432-1.
short: M. Riedl, I.D. Mayer, J. Merrin, M.K. Sixt, B. Hof, Nature Communications
14 (2023).
date_created: 2023-09-24T22:01:10Z
date_published: 2023-09-13T00:00:00Z
date_updated: 2023-12-13T12:29:41Z
day: '13'
ddc:
- '530'
- '570'
department:
- _id: MiSi
- _id: NanoFab
- _id: BjHo
doi: 10.1038/s41467-023-41432-1
ec_funded: 1
external_id:
isi:
- '001087583700030'
pmid:
- '37704595'
file:
- access_level: open_access
checksum: 82d2d4ad736cc8493db8ce45cd313f7b
content_type: application/pdf
creator: dernst
date_created: 2023-09-25T08:32:37Z
date_updated: 2023-09-25T08:32:37Z
file_id: '14366'
file_name: 2023_NatureComm_Riedl.pdf
file_size: 2317272
relation: main_file
success: 1
file_date_updated: 2023-09-25T08:32:37Z
has_accepted_license: '1'
intvolume: ' 14'
isi: 1
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
pmid: 1
project:
- _id: 25A603A2-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '281556'
name: Cytoskeletal force generation and force transduction of migrating leukocytes
- _id: 25FE9508-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '724373'
name: Cellular navigation along spatial gradients
publication: Nature Communications
publication_identifier:
eissn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Synchronization in collectively moving inanimate and living active matter
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 14
year: '2023'
...
---
_id: '14754'
abstract:
- lang: eng
text: The large-scale laminar/turbulent spiral patterns that appear in the linearly
unstable regime of counter-rotating Taylor–Couette flow are investigated from
a statistical perspective by means of direct numerical simulation. Unlike the
vast majority of previous numerical studies, we analyse the flow in periodic parallelogram-annular
domains, following a coordinate change that aligns one of the parallelogram sides
with the spiral pattern. The domain size, shape and spatial resolution have been
varied and the results compared with those in a sufficiently large computational
orthogonal domain with natural axial and azimuthal periodicity. We find that a
minimal parallelogram of the right tilt significantly reduces the computational
cost without notably compromising the statistical properties of the supercritical
turbulent spiral. Its mean structure, obtained from extremely long time integrations
in a co-rotating reference frame using the method of slices, bears remarkable
similarity with the turbulent stripes observed in plane Couette flow, the centrifugal
instability playing only a secondary role.
acknowledgement: K.D.’s research was supported by Australian Research Council Discovery
Early Career Researcher Award (DE170100171). B.W., R.A., F.M. and A.M. research
was supported by the Spanish Ministerio de Economía y Competitividad (grant nos.
FIS2016-77849-R and FIS2017-85794-P) and Ministerio de Ciencia e Innovación (grant
no. PID2020-114043GB-I00) and the Generalitat de Catalunya (grant no. 2017-SGR-785).
B.W.’s research was also supported by the Chinese Scholarship Council (grant CSC
no. 201806440152). F.M. is a Serra-Húnter Fellow.
article_number: '0112'
article_processing_charge: No
article_type: original
author:
- first_name: B.
full_name: Wang, B.
last_name: Wang
- first_name: F.
full_name: Mellibovsky, F.
last_name: Mellibovsky
- first_name: Roger
full_name: Ayats López, Roger
id: ab77522d-073b-11ed-8aff-e71b39258362
last_name: Ayats López
orcid: 0000-0001-6572-0621
- first_name: K.
full_name: Deguchi, K.
last_name: Deguchi
- first_name: A.
full_name: Meseguer, A.
last_name: Meseguer
citation:
ama: Wang B, Mellibovsky F, Ayats López R, Deguchi K, Meseguer A. Mean structure
of the supercritical turbulent spiral in Taylor–Couette flow. Philosophical
Transactions of the Royal Society A. 2023;381(2246). doi:10.1098/rsta.2022.0112
apa: Wang, B., Mellibovsky, F., Ayats López, R., Deguchi, K., & Meseguer, A.
(2023). Mean structure of the supercritical turbulent spiral in Taylor–Couette
flow. Philosophical Transactions of the Royal Society A. The Royal Society.
https://doi.org/10.1098/rsta.2022.0112
chicago: Wang, B., F. Mellibovsky, Roger Ayats López, K. Deguchi, and A. Meseguer.
“Mean Structure of the Supercritical Turbulent Spiral in Taylor–Couette Flow.”
Philosophical Transactions of the Royal Society A. The Royal Society, 2023.
https://doi.org/10.1098/rsta.2022.0112.
ieee: B. Wang, F. Mellibovsky, R. Ayats López, K. Deguchi, and A. Meseguer, “Mean
structure of the supercritical turbulent spiral in Taylor–Couette flow,” Philosophical
Transactions of the Royal Society A, vol. 381, no. 2246. The Royal Society,
2023.
ista: Wang B, Mellibovsky F, Ayats López R, Deguchi K, Meseguer A. 2023. Mean structure
of the supercritical turbulent spiral in Taylor–Couette flow. Philosophical Transactions
of the Royal Society A. 381(2246), 0112.
mla: Wang, B., et al. “Mean Structure of the Supercritical Turbulent Spiral in Taylor–Couette
Flow.” Philosophical Transactions of the Royal Society A, vol. 381, no.
2246, 0112, The Royal Society, 2023, doi:10.1098/rsta.2022.0112.
short: B. Wang, F. Mellibovsky, R. Ayats López, K. Deguchi, A. Meseguer, Philosophical
Transactions of the Royal Society A 381 (2023).
date_created: 2024-01-08T13:11:45Z
date_published: 2023-05-01T00:00:00Z
date_updated: 2024-01-09T09:15:29Z
day: '01'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1098/rsta.2022.0112
external_id:
pmid:
- '36907214'
file:
- access_level: open_access
checksum: 1978d126c0ce2f47c22ac20107cc0106
content_type: application/pdf
creator: dernst
date_created: 2024-01-09T09:13:53Z
date_updated: 2024-01-09T09:13:53Z
file_id: '14763'
file_name: 2023_PhilTransactionsA_Wang_accepted.pdf
file_size: 6421086
relation: main_file
success: 1
file_date_updated: 2024-01-09T09:13:53Z
has_accepted_license: '1'
intvolume: ' 381'
issue: '2246'
keyword:
- General Physics and Astronomy
- General Engineering
- General Mathematics
language:
- iso: eng
month: '05'
oa: 1
oa_version: Submitted Version
pmid: 1
publication: Philosophical Transactions of the Royal Society A
publication_identifier:
eissn:
- 1471-2962
issn:
- 1364-503X
publication_status: published
publisher: The Royal Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Mean structure of the supercritical turbulent spiral in Taylor–Couette flow
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 381
year: '2023'
...
---
_id: '14466'
abstract:
- lang: eng
text: The first long-lived turbulent structures observable in planar shear flows
take the form of localized stripes, inclined with respect to the mean flow direction.
The dynamics of these stripes is central to transition, and recent studies proposed
an analogy to directed percolation where the stripes’ proliferation is ultimately
responsible for the turbulence becoming sustained. In the present study we focus
on the internal stripe dynamics as well as on the eventual stripe expansion, and
we compare the underlying mechanisms in pressure- and shear-driven planar flows,
respectively, plane-Poiseuille and plane-Couette flow. Despite the similarities
of the overall laminar–turbulence patterns, the stripe proliferation processes
in the two cases are fundamentally different. Starting from the growth and sustenance
of individual stripes, we find that in plane-Couette flow new streaks are created
stochastically throughout the stripe whereas in plane-Poiseuille flow streak creation
is deterministic and occurs locally at the downstream tip. Because of the up/downstream
symmetry, Couette stripes, in contrast to Poiseuille stripes, have two weak and
two strong laminar turbulent interfaces. These differences in symmetry as well
as in internal growth give rise to two fundamentally different stripe splitting
mechanisms. In plane-Poiseuille flow splitting is connected to the elongational
growth of the original stripe, and it results from a break-off/shedding of the
stripe's tail. In plane-Couette flow splitting follows from a broadening of the
original stripe and a division along the stripe into two slimmer stripes.
acknowledgement: E.M. acknowledges funding from the ISTplus fellowship programme.
G.Y. and B.H. acknowledge a grant from the Simons Foundation (662960, BH).
article_number: A21
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Elena
full_name: Marensi, Elena
id: 0BE7553A-1004-11EA-B805-18983DDC885E
last_name: Marensi
orcid: 0000-0001-7173-4923
- first_name: Gökhan
full_name: Yalniz, Gökhan
id: 66E74FA2-D8BF-11E9-8249-8DE2E5697425
last_name: Yalniz
orcid: 0000-0002-8490-9312
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Marensi E, Yalniz G, Hof B. Dynamics and proliferation of turbulent stripes
in plane-Poiseuille and plane-Couette flows. Journal of Fluid Mechanics.
2023;974. doi:10.1017/jfm.2023.780
apa: Marensi, E., Yalniz, G., & Hof, B. (2023). Dynamics and proliferation of
turbulent stripes in plane-Poiseuille and plane-Couette flows. Journal of Fluid
Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2023.780
chicago: Marensi, Elena, Gökhan Yalniz, and Björn Hof. “Dynamics and Proliferation
of Turbulent Stripes in Plane-Poiseuille and Plane-Couette Flows.” Journal
of Fluid Mechanics. Cambridge University Press, 2023. https://doi.org/10.1017/jfm.2023.780.
ieee: E. Marensi, G. Yalniz, and B. Hof, “Dynamics and proliferation of turbulent
stripes in plane-Poiseuille and plane-Couette flows,” Journal of Fluid Mechanics,
vol. 974. Cambridge University Press, 2023.
ista: Marensi E, Yalniz G, Hof B. 2023. Dynamics and proliferation of turbulent
stripes in plane-Poiseuille and plane-Couette flows. Journal of Fluid Mechanics.
974, A21.
mla: Marensi, Elena, et al. “Dynamics and Proliferation of Turbulent Stripes in
Plane-Poiseuille and Plane-Couette Flows.” Journal of Fluid Mechanics,
vol. 974, A21, Cambridge University Press, 2023, doi:10.1017/jfm.2023.780.
short: E. Marensi, G. Yalniz, B. Hof, Journal of Fluid Mechanics 974 (2023).
date_created: 2023-10-30T09:32:28Z
date_published: 2023-11-10T00:00:00Z
date_updated: 2024-02-15T09:06:23Z
day: '10'
ddc:
- '530'
department:
- _id: GradSch
- _id: BjHo
doi: 10.1017/jfm.2023.780
external_id:
arxiv:
- '2212.12406'
isi:
- '001088363700001'
file:
- access_level: open_access
checksum: 17c64c1fb0d5f73252364bf98b0b9e1a
content_type: application/pdf
creator: dernst
date_created: 2024-02-15T09:05:21Z
date_updated: 2024-02-15T09:05:21Z
file_id: '14996'
file_name: 2023_JourFluidMechanics_Marensi.pdf
file_size: 2804641
relation: main_file
success: 1
file_date_updated: 2024-02-15T09:05:21Z
has_accepted_license: '1'
intvolume: ' 974'
isi: 1
keyword:
- turbulence
- transition to turbulence
- patterns
language:
- iso: eng
month: '11'
oa: 1
oa_version: Published Version
project:
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
grant_number: '662960'
name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
Studies on Transitional and Turbulent Flows'
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
status: public
title: Dynamics and proliferation of turbulent stripes in plane-Poiseuille and plane-Couette
flows
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 974
year: '2023'
...
---
_id: '14641'
acknowledged_ssus:
- _id: LifeSc
- _id: Bio
- _id: CampIT
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Mike
full_name: Hennessey-Wesen, Mike
id: 3F338C72-F248-11E8-B48F-1D18A9856A87
last_name: Hennessey-Wesen
citation:
ama: Hennessey-Wesen M. Adaptive mutation in E. coli modulated by luxS. 2023. doi:10.15479/at:ista:14641
apa: Hennessey-Wesen, M. (2023). Adaptive mutation in E. coli modulated by luxS.
Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:14641
chicago: Hennessey-Wesen, Mike. “Adaptive Mutation in E. Coli Modulated by LuxS.”
Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:14641.
ieee: M. Hennessey-Wesen, “Adaptive mutation in E. coli modulated by luxS,” Institute
of Science and Technology Austria, 2023.
ista: Hennessey-Wesen M. 2023. Adaptive mutation in E. coli modulated by luxS. Institute
of Science and Technology Austria.
mla: Hennessey-Wesen, Mike. Adaptive Mutation in E. Coli Modulated by LuxS.
Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:14641.
short: M. Hennessey-Wesen, Adaptive Mutation in E. Coli Modulated by LuxS, Institute
of Science and Technology Austria, 2023.
date_created: 2023-12-04T13:17:37Z
date_published: 2023-11-30T00:00:00Z
date_updated: 2024-03-22T13:21:17Z
day: '30'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: GradSch
- _id: BjHo
doi: 10.15479/at:ista:14641
ec_funded: 1
file:
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checksum: 4127c285b34f4bf7fb31ef24f9d14c25
content_type: application/vnd.oasis.opendocument.text
creator: mhenness
date_created: 2023-12-06T13:13:26Z
date_updated: 2023-12-06T13:13:26Z
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file_size: 46405919
relation: source_file
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creator: mhenness
date_created: 2023-12-06T13:14:15Z
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content_type: application/pdf
creator: cchlebak
date_created: 2024-03-20T13:19:36Z
date_updated: 2024-03-20T13:19:36Z
file_id: '15145'
file_name: 2023_Hennessey_Michael_Thesis_from_source.pdf
file_size: 2930287
relation: other
file_date_updated: 2024-03-20T13:19:36Z
has_accepted_license: '1'
keyword:
- microfluidics
- miceobiology
- mutations
- quorum sensing
language:
- iso: eng
month: '11'
oa_version: Published Version
page: '104'
project:
- _id: 2564DBCA-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '665385'
name: International IST Doctoral Program
publication_identifier:
issn:
- 2663 - 337X
publication_status: published
publisher: Institute of Science and Technology Austria
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: Adaptive mutation in E. coli modulated by luxS
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2023'
...
---
_id: '12134'
abstract:
- lang: eng
text: Standard epidemic models exhibit one continuous, second order phase transition
to macroscopic outbreaks. However, interventions to control outbreaks may fundamentally
alter epidemic dynamics. Here we reveal how such interventions modify the type
of phase transition. In particular, we uncover three distinct types of explosive
phase transitions for epidemic dynamics with capacity-limited interventions. Depending
on the capacity limit, interventions may (i) leave the standard second order phase
transition unchanged but exponentially suppress the probability of large outbreaks,
(ii) induce a first-order discontinuous transition to macroscopic outbreaks, or
(iii) cause a secondary explosive yet continuous third-order transition. These
insights highlight inherent limitations in predicting and containing epidemic
outbreaks. More generally our study offers a cornerstone example of a third-order
explosive phase transition in complex systems.
acknowledgement: We acknowledge support from the Volkswagen Foundation under Grant
No. 99720 and the German Federal Ministry for Education and Research (BMBF) under
Grant No. 16ICR01. This research was supported by the Deutsche Forschungsgemeinschaft
(DFG, German Research Foundation) under Germany’s Excellence Strategy—EXC-2068—390729961—Cluster
of Excellence Physics of Life of TU Dresden.
article_number: 04LT02
article_processing_charge: No
article_type: original
author:
- first_name: Georg
full_name: Börner, Georg
last_name: Börner
- first_name: Malte
full_name: Schröder, Malte
last_name: Schröder
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
- first_name: Marc
full_name: Timme, Marc
last_name: Timme
citation:
ama: 'Börner G, Schröder M, Scarselli D, Budanur NB, Hof B, Timme M. Explosive transitions
in epidemic dynamics. Journal of Physics: Complexity. 2022;3(4). doi:10.1088/2632-072x/ac99cd'
apa: 'Börner, G., Schröder, M., Scarselli, D., Budanur, N. B., Hof, B., & Timme,
M. (2022). Explosive transitions in epidemic dynamics. Journal of Physics:
Complexity. IOP Publishing. https://doi.org/10.1088/2632-072x/ac99cd'
chicago: 'Börner, Georg, Malte Schröder, Davide Scarselli, Nazmi B Budanur, Björn
Hof, and Marc Timme. “Explosive Transitions in Epidemic Dynamics.” Journal
of Physics: Complexity. IOP Publishing, 2022. https://doi.org/10.1088/2632-072x/ac99cd.'
ieee: 'G. Börner, M. Schröder, D. Scarselli, N. B. Budanur, B. Hof, and M. Timme,
“Explosive transitions in epidemic dynamics,” Journal of Physics: Complexity,
vol. 3, no. 4. IOP Publishing, 2022.'
ista: 'Börner G, Schröder M, Scarselli D, Budanur NB, Hof B, Timme M. 2022. Explosive
transitions in epidemic dynamics. Journal of Physics: Complexity. 3(4), 04LT02.'
mla: 'Börner, Georg, et al. “Explosive Transitions in Epidemic Dynamics.” Journal
of Physics: Complexity, vol. 3, no. 4, 04LT02, IOP Publishing, 2022, doi:10.1088/2632-072x/ac99cd.'
short: 'G. Börner, M. Schröder, D. Scarselli, N.B. Budanur, B. Hof, M. Timme, Journal
of Physics: Complexity 3 (2022).'
date_created: 2023-01-12T12:03:43Z
date_published: 2022-10-25T00:00:00Z
date_updated: 2023-02-13T09:15:13Z
day: '25'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1088/2632-072x/ac99cd
file:
- access_level: open_access
checksum: 35c5c5cb0eb17ea1b5184755daab9fc9
content_type: application/pdf
creator: dernst
date_created: 2023-01-24T07:24:37Z
date_updated: 2023-01-24T07:24:37Z
file_id: '12350'
file_name: 2022_JourPhysics_Boerner.pdf
file_size: 1006106
relation: main_file
success: 1
file_date_updated: 2023-01-24T07:24:37Z
has_accepted_license: '1'
intvolume: ' 3'
issue: '4'
keyword:
- Artificial Intelligence
- Computer Networks and Communications
- Computer Science Applications
- Information Systems
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
publication: 'Journal of Physics: Complexity'
publication_identifier:
issn:
- 2632-072X
publication_status: published
publisher: IOP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: Explosive transitions in epidemic dynamics
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 3
year: '2022'
...
---
_id: '10654'
abstract:
- lang: eng
text: "Directed percolation (DP) has recently emerged as a possible solution to
the century old puzzle surrounding the transition to turbulence. Multiple model
studies reported DP exponents, however, experimental evidence is limited since
the largest possible observation times are orders of magnitude shorter than the
flows’ characteristic timescales. An exception is cylindrical Couette flow where
the limit is not temporal, but rather the realizable system size. We present experiments
in a Couette setup of unprecedented azimuthal and axial aspect ratios. Approaching
the critical point to within less than 0.1% we determine five critical exponents,
all of which are in excellent agreement with the 2+1D DP universality class. The
complex dynamics encountered at \r\nthe onset of turbulence can hence be fully
rationalized within the framework of statistical mechanics."
acknowledged_ssus:
- _id: M-Shop
acknowledgement: "We thank T.Menner, T.Asenov, P. Maier and the Miba machine shop
of IST Austria for their valuable support in all technical aspects. We thank Marc
Avila for comments on the manuscript. This work was supported by a grant from the
Simons Foundation (662960, B.H.). We acknowledge the European Research Council under
the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement
306589 for financial support. K.A.\r\nacknowledges funding from the Central Research
Development Fund of the University of Bremen, grant number ZF04B /2019/FB04 Avila
Kerstin (”Independent Project for Postdocs”). L.K. was supported by the European
Union’s Horizon 2020 Research and innovation programme under the Marie Sklodowska-Curie
grant agreement No. 754411.\r\n"
article_number: '014502'
article_processing_charge: No
article_type: original
author:
- first_name: Lukasz
full_name: Klotz, Lukasz
id: 2C9AF1C2-F248-11E8-B48F-1D18A9856A87
last_name: Klotz
orcid: 0000-0003-1740-7635
- first_name: Grégoire M
full_name: Lemoult, Grégoire M
id: 4787FE80-F248-11E8-B48F-1D18A9856A87
last_name: Lemoult
- first_name: Kerstin
full_name: Avila, Kerstin
last_name: Avila
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Klotz L, Lemoult GM, Avila K, Hof B. Phase transition to turbulence in spatially
extended shear flows. Physical Review Letters. 2022;128(1). doi:10.1103/PhysRevLett.128.014502
apa: Klotz, L., Lemoult, G. M., Avila, K., & Hof, B. (2022). Phase transition
to turbulence in spatially extended shear flows. Physical Review Letters.
American Physical Society. https://doi.org/10.1103/PhysRevLett.128.014502
chicago: Klotz, Lukasz, Grégoire M Lemoult, Kerstin Avila, and Björn Hof. “Phase
Transition to Turbulence in Spatially Extended Shear Flows.” Physical Review
Letters. American Physical Society, 2022. https://doi.org/10.1103/PhysRevLett.128.014502.
ieee: L. Klotz, G. M. Lemoult, K. Avila, and B. Hof, “Phase transition to turbulence
in spatially extended shear flows,” Physical Review Letters, vol. 128,
no. 1. American Physical Society, 2022.
ista: Klotz L, Lemoult GM, Avila K, Hof B. 2022. Phase transition to turbulence
in spatially extended shear flows. Physical Review Letters. 128(1), 014502.
mla: Klotz, Lukasz, et al. “Phase Transition to Turbulence in Spatially Extended
Shear Flows.” Physical Review Letters, vol. 128, no. 1, 014502, American
Physical Society, 2022, doi:10.1103/PhysRevLett.128.014502.
short: L. Klotz, G.M. Lemoult, K. Avila, B. Hof, Physical Review Letters 128 (2022).
date_created: 2022-01-23T23:01:28Z
date_published: 2022-01-05T00:00:00Z
date_updated: 2023-08-02T13:59:19Z
day: '05'
department:
- _id: BjHo
doi: 10.1103/PhysRevLett.128.014502
ec_funded: 1
external_id:
arxiv:
- '2111.14894'
isi:
- '000748271700010'
pmid:
- '35061458'
intvolume: ' 128'
isi: 1
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2111.14894
month: '01'
oa: 1
oa_version: Preprint
pmid: 1
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
grant_number: '662960'
name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
Studies on Transitional and Turbulent Flows'
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Phase transition to turbulence in spatially extended shear flows
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 128
year: '2022'
...
---
_id: '11704'
abstract:
- lang: eng
text: In Fall 2020, several European countries reported rapid increases in COVID-19
cases along with growing estimates of the effective reproduction rates. Such an
acceleration in epidemic spread is usually attributed to time-dependent effects,
e.g. human travel, seasonal behavioral changes, mutations of the pathogen etc.
In this case however the acceleration occurred when counter measures such as testing
and contact tracing exceeded their capacity limit. Considering Austria as an example,
here we show that this dynamics can be captured by a time-independent, i.e. autonomous,
compartmental model that incorporates these capacity limits. In this model, the
epidemic acceleration coincides with the exhaustion of mitigation efforts, resulting
in an increasing fraction of undetected cases that drive the effective reproduction
rate progressively higher. We demonstrate that standard models which does not
include this effect necessarily result in a systematic underestimation of the
effective reproduction rate.
article_number: e0269975
article_processing_charge: No
article_type: original
author:
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Budanur NB, Hof B. An autonomous compartmental model for accelerating epidemics.
PLoS ONE. 2022;17(7). doi:10.1371/journal.pone.0269975
apa: Budanur, N. B., & Hof, B. (2022). An autonomous compartmental model for
accelerating epidemics. PLoS ONE. Public Library of Science. https://doi.org/10.1371/journal.pone.0269975
chicago: Budanur, Nazmi B, and Björn Hof. “An Autonomous Compartmental Model for
Accelerating Epidemics.” PLoS ONE. Public Library of Science, 2022. https://doi.org/10.1371/journal.pone.0269975.
ieee: N. B. Budanur and B. Hof, “An autonomous compartmental model for accelerating
epidemics,” PLoS ONE, vol. 17, no. 7. Public Library of Science, 2022.
ista: Budanur NB, Hof B. 2022. An autonomous compartmental model for accelerating
epidemics. PLoS ONE. 17(7), e0269975.
mla: Budanur, Nazmi B., and Björn Hof. “An Autonomous Compartmental Model for Accelerating
Epidemics.” PLoS ONE, vol. 17, no. 7, e0269975, Public Library of Science,
2022, doi:10.1371/journal.pone.0269975.
short: N.B. Budanur, B. Hof, PLoS ONE 17 (2022).
date_created: 2022-07-31T22:01:48Z
date_published: 2022-07-18T00:00:00Z
date_updated: 2023-08-03T12:24:22Z
day: '18'
ddc:
- '510'
department:
- _id: BjHo
doi: 10.1371/journal.pone.0269975
external_id:
isi:
- '000911392100055'
file:
- access_level: open_access
checksum: 1ddd9b91e6dec31ab0e7a8433ca2d452
content_type: application/pdf
creator: dernst
date_created: 2022-08-01T08:02:38Z
date_updated: 2022-08-01T08:02:38Z
file_id: '11712'
file_name: 2022_PLoSONE_Budanur.pdf
file_size: 1421256
relation: main_file
success: 1
file_date_updated: 2022-08-01T08:02:38Z
has_accepted_license: '1'
intvolume: ' 17'
isi: 1
issue: '7'
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
publication: PLoS ONE
publication_identifier:
eissn:
- 1932-6203
publication_status: published
publisher: Public Library of Science
quality_controlled: '1'
related_material:
record:
- id: '11711'
relation: research_data
status: public
scopus_import: '1'
status: public
title: An autonomous compartmental model for accelerating epidemics
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 17
year: '2022'
...
---
_id: '11711'
abstract:
- lang: eng
text: Codes and data for reproducing the results of N. B. Budanur and B. Hof "An
autonomous compartmental model for accelerating epidemics"
article_processing_charge: No
author:
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
citation:
ama: Budanur NB. burakbudanur/autoacc-public. 2022. doi:10.5281/ZENODO.6802720
apa: Budanur, N. B. (2022). burakbudanur/autoacc-public. Zenodo. https://doi.org/10.5281/ZENODO.6802720
chicago: Budanur, Nazmi B. “Burakbudanur/Autoacc-Public.” Zenodo, 2022. https://doi.org/10.5281/ZENODO.6802720.
ieee: N. B. Budanur, “burakbudanur/autoacc-public.” Zenodo, 2022.
ista: Budanur NB. 2022. burakbudanur/autoacc-public, Zenodo, 10.5281/ZENODO.6802720.
mla: Budanur, Nazmi B. Burakbudanur/Autoacc-Public. Zenodo, 2022, doi:10.5281/ZENODO.6802720.
short: N.B. Budanur, (2022).
date_created: 2022-08-01T08:06:33Z
date_published: 2022-07-06T00:00:00Z
date_updated: 2023-08-03T12:24:21Z
day: '06'
ddc:
- '000'
department:
- _id: BjHo
doi: 10.5281/ZENODO.6802720
has_accepted_license: '1'
license: https://creativecommons.org/publicdomain/zero/1.0/
main_file_link:
- open_access: '1'
url: https://doi.org/10.5281/ZENODO.6802720
month: '07'
oa: 1
oa_version: Published Version
publisher: Zenodo
related_material:
record:
- id: '11704'
relation: used_in_publication
status: public
status: public
title: burakbudanur/autoacc-public
tmp:
image: /images/cc_0.png
legal_code_url: https://creativecommons.org/publicdomain/zero/1.0/legalcode
name: Creative Commons Public Domain Dedication (CC0 1.0)
short: CC0 (1.0)
type: research_data_reference
user_id: 6785fbc1-c503-11eb-8a32-93094b40e1cf
year: '2022'
...
---
_id: '10820'
abstract:
- lang: eng
text: Streaky structures in the boundary layers are often generated by surface roughness
elements and/or free-stream turbulence, and are known to have significant effects
on boundary-layer instability. In this paper, we investigate the impact of two
forms of streaks on the instability of supersonic boundary layers. The first concerns
the streaks generated by an array of spanwise periodic and streamwise elongated
surface roughness elements, and our interest is how these streaks influence the
lower-branch viscous first modes, whose characteristic wavelength and frequency
are on the classical triple-deck scales. By adapting the triple-deck theory in
the incompressible regime to the supersonic one, we first derived a simplified
system which allows for efficient calculation of the streaks. The asymptotic analysis
simplifies a bi-global eigenvalue problem to a one-dimensional problem in the
spanwise direction, showing that the instability is controlled at leading order
solely by the spanwise-dependent wall shear. In the fundamental configuration,
the streaks stabilize first modes at low frequencies but destabilize the high-frequency
ones. In the subharmonic configuration, the streaks generally destabilize the
first mode across the entire frequency band. Importantly, the spanwise even modes
are of radiating nature, i.e. they emit acoustic waves spontaneously to the far
field. Streaks of the second form are generated by low-frequency vortical disturbances
representing free-stream turbulence. They alter the flow in the entire layer and
their effects on instability are investigated by solving the inviscid bi-global
eigenvalue problem. Different from the incompressible case, a multitude of compressible
instability modes exists, of which the dominant mode is an inviscid instability
associated with the spanwise shear. In addition, there exists a separate branch
of instability modes that have smaller growth rates but are spontaneously radiating.
acknowledgement: The work is supported by the National Key Research and Development
Program of China (No. 2016YFA0401200), the National Natural Science Foundation of
China (Grant Nos. 91952202 and 11402167).
article_processing_charge: No
author:
- first_name: Jianxin
full_name: Liu, Jianxin
last_name: Liu
- first_name: Elena
full_name: Marensi, Elena
id: 0BE7553A-1004-11EA-B805-18983DDC885E
last_name: Marensi
- first_name: Xuesong
full_name: Wu, Xuesong
last_name: Wu
citation:
ama: 'Liu J, Marensi E, Wu X. Effects of streaky structures on the instability of
supersonic boundary layers. In: Sherwin S, Schmid P, Wu X, eds. IUTAM Laminar-Turbulent
Transition. Vol 38. 1st ed. IUTAM Bookseries. Cham: Springer Nature; 2022:587-598.
doi:10.1007/978-3-030-67902-6_51'
apa: 'Liu, J., Marensi, E., & Wu, X. (2022). Effects of streaky structures on
the instability of supersonic boundary layers. In S. Sherwin, P. Schmid, &
X. Wu (Eds.), IUTAM Laminar-Turbulent Transition (1st ed., Vol. 38, pp.
587–598). Cham: Springer Nature. https://doi.org/10.1007/978-3-030-67902-6_51'
chicago: 'Liu, Jianxin, Elena Marensi, and Xuesong Wu. “Effects of Streaky Structures
on the Instability of Supersonic Boundary Layers.” In IUTAM Laminar-Turbulent
Transition, edited by Spencer Sherwin, Peter Schmid, and Xuesong Wu, 1st ed.,
38:587–98. IUTAM Bookseries. Cham: Springer Nature, 2022. https://doi.org/10.1007/978-3-030-67902-6_51.'
ieee: 'J. Liu, E. Marensi, and X. Wu, “Effects of streaky structures on the instability
of supersonic boundary layers,” in IUTAM Laminar-Turbulent Transition,
1st ed., vol. 38, S. Sherwin, P. Schmid, and X. Wu, Eds. Cham: Springer Nature,
2022, pp. 587–598.'
ista: 'Liu J, Marensi E, Wu X. 2022.Effects of streaky structures on the instability
of supersonic boundary layers. In: IUTAM Laminar-Turbulent Transition. vol. 38,
587–598.'
mla: Liu, Jianxin, et al. “Effects of Streaky Structures on the Instability of Supersonic
Boundary Layers.” IUTAM Laminar-Turbulent Transition, edited by Spencer
Sherwin et al., 1st ed., vol. 38, Springer Nature, 2022, pp. 587–98, doi:10.1007/978-3-030-67902-6_51.
short: J. Liu, E. Marensi, X. Wu, in:, S. Sherwin, P. Schmid, X. Wu (Eds.), IUTAM
Laminar-Turbulent Transition, 1st ed., Springer Nature, Cham, 2022, pp. 587–598.
conference:
end_date: 2019-09-06
location: London, United Kingdom
name: IUTAM Symposium
start_date: 2019-09-02
date_created: 2022-03-04T09:14:34Z
date_published: 2022-01-01T00:00:00Z
date_updated: 2023-08-03T12:54:59Z
day: '01'
department:
- _id: BjHo
doi: 10.1007/978-3-030-67902-6_51
edition: '1'
editor:
- first_name: Spencer
full_name: Sherwin, Spencer
last_name: Sherwin
- first_name: Peter
full_name: Schmid, Peter
last_name: Schmid
- first_name: Xuesong
full_name: Wu, Xuesong
last_name: Wu
external_id:
isi:
- '000709087600051'
intvolume: ' 38'
isi: 1
language:
- iso: eng
month: '01'
oa_version: None
page: 587-598
place: Cham
publication: IUTAM Laminar-Turbulent Transition
publication_identifier:
eisbn:
- '9783030679026'
eissn:
- 1875-3493
isbn:
- '9783030679019'
issn:
- 1875-3507
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
series_title: IUTAM Bookseries
status: public
title: Effects of streaky structures on the instability of supersonic boundary layers
type: book_chapter
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 38
year: '2022'
...
---
_id: '12137'
abstract:
- lang: eng
text: We investigate the local self-sustained process underlying spiral turbulence
in counter-rotating Taylor–Couette flow using a periodic annular domain, shaped
as a parallelogram, two of whose sides are aligned with the cylindrical helix
described by the spiral pattern. The primary focus of the study is placed on the
emergence of drifting–rotating waves (DRW) that capture, in a relatively small
domain, the main features of coherent structures typically observed in developed
turbulence. The transitional dynamics of the subcritical region, far below the
first instability of the laminar circular Couette flow, is determined by the upper
and lower branches of DRW solutions originated at saddle-node bifurcations. The
mechanism whereby these solutions self-sustain, and the chaotic dynamics they
induce, are conspicuously reminiscent of other subcritical shear flows. Remarkably,
the flow properties of DRW persist even as the Reynolds number is increased beyond
the linear stability threshold of the base flow. Simulations in a narrow parallelogram
domain stretched in the azimuthal direction to revolve around the apparatus a
full turn confirm that self-sustained vortices eventually concentrate into a localised
pattern. The resulting statistical steady state satisfactorily reproduces qualitatively,
and to a certain degree also quantitatively, the topology and properties of spiral
turbulence as calculated in a large periodic domain of sufficient aspect ratio
that is representative of the real system.
acknowledgement: "K.D.’s research was supported by an Australian Research Council
Discovery Early Career\r\nResearcher Award (DE170100171). B.W., R.A., F.M. and A.M.
research was supported by the Spanish Ministerio de Economía y Competitivdad (grant
numbers FIS2016-77849-R and FIS2017-85794-P) and Ministerio de Ciencia e Innovación
(grant number PID2020-114043GB-I00) and the Generalitat de Catalunya (grant 2017-SGR-785).
B.W.’s research was also supported by the Chinese Scholarship Council (grant CSC
no. 201806440152)."
article_number: A21
article_processing_charge: No
article_type: original
author:
- first_name: B.
full_name: Wang, B.
last_name: Wang
- first_name: Roger
full_name: Ayats López, Roger
id: ab77522d-073b-11ed-8aff-e71b39258362
last_name: Ayats López
orcid: 0000-0001-6572-0621
- first_name: K.
full_name: Deguchi, K.
last_name: Deguchi
- first_name: F.
full_name: Mellibovsky, F.
last_name: Mellibovsky
- first_name: A.
full_name: Meseguer, A.
last_name: Meseguer
citation:
ama: Wang B, Ayats López R, Deguchi K, Mellibovsky F, Meseguer A. Self-sustainment
of coherent structures in counter-rotating Taylor–Couette flow. Journal of
Fluid Mechanics. 2022;951. doi:10.1017/jfm.2022.828
apa: Wang, B., Ayats López, R., Deguchi, K., Mellibovsky, F., & Meseguer, A.
(2022). Self-sustainment of coherent structures in counter-rotating Taylor–Couette
flow. Journal of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2022.828
chicago: Wang, B., Roger Ayats López, K. Deguchi, F. Mellibovsky, and A. Meseguer.
“Self-Sustainment of Coherent Structures in Counter-Rotating Taylor–Couette Flow.”
Journal of Fluid Mechanics. Cambridge University Press, 2022. https://doi.org/10.1017/jfm.2022.828.
ieee: B. Wang, R. Ayats López, K. Deguchi, F. Mellibovsky, and A. Meseguer, “Self-sustainment
of coherent structures in counter-rotating Taylor–Couette flow,” Journal of
Fluid Mechanics, vol. 951. Cambridge University Press, 2022.
ista: Wang B, Ayats López R, Deguchi K, Mellibovsky F, Meseguer A. 2022. Self-sustainment
of coherent structures in counter-rotating Taylor–Couette flow. Journal of Fluid
Mechanics. 951, A21.
mla: Wang, B., et al. “Self-Sustainment of Coherent Structures in Counter-Rotating
Taylor–Couette Flow.” Journal of Fluid Mechanics, vol. 951, A21, Cambridge
University Press, 2022, doi:10.1017/jfm.2022.828.
short: B. Wang, R. Ayats López, K. Deguchi, F. Mellibovsky, A. Meseguer, Journal
of Fluid Mechanics 951 (2022).
date_created: 2023-01-12T12:04:17Z
date_published: 2022-11-07T00:00:00Z
date_updated: 2023-08-04T08:54:16Z
day: '07'
department:
- _id: BjHo
doi: 10.1017/jfm.2022.828
external_id:
arxiv:
- '2207.12990'
isi:
- '000879446900001'
intvolume: ' 951'
isi: 1
keyword:
- Mechanical Engineering
- Mechanics of Materials
- Condensed Matter Physics
- Applied Mathematics
language:
- iso: eng
main_file_link:
- open_access: '1'
url: ' https://doi.org/10.48550/arXiv.2207.12990'
month: '11'
oa: 1
oa_version: Preprint
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Self-sustainment of coherent structures in counter-rotating Taylor–Couette
flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 951
year: '2022'
...
---
_id: '12259'
abstract:
- lang: eng
text: 'Theoretical foundations of chaos have been predominantly laid out for finite-dimensional
dynamical systems, such as the three-body problem in classical mechanics and the
Lorenz model in dissipative systems. In contrast, many real-world chaotic phenomena,
e.g., weather, arise in systems with many (formally infinite) degrees of freedom,
which limits direct quantitative analysis of such systems using chaos theory.
In the present work, we demonstrate that the hydrodynamic pilot-wave systems offer
a bridge between low- and high-dimensional chaotic phenomena by allowing for a
systematic study of how the former connects to the latter. Specifically, we present
experimental results, which show the formation of low-dimensional chaotic attractors
upon destabilization of regular dynamics and a final transition to high-dimensional
chaos via the merging of distinct chaotic regions through a crisis bifurcation.
Moreover, we show that the post-crisis dynamics of the system can be rationalized
as consecutive scatterings from the nonattracting chaotic sets with lifetimes
following exponential distributions. '
acknowledgement: 'This work was partially funded by the Institute of Science and Technology
Austria Interdisciplinary Project Committee Grant “Pilot-Wave Hydrodynamics: Chaos
and Quantum Analogies.”'
article_number: '093138'
article_processing_charge: No
article_type: original
author:
- first_name: George H
full_name: Choueiri, George H
id: 448BD5BC-F248-11E8-B48F-1D18A9856A87
last_name: Choueiri
- first_name: Balachandra
full_name: Suri, Balachandra
id: 47A5E706-F248-11E8-B48F-1D18A9856A87
last_name: Suri
- first_name: Jack
full_name: Merrin, Jack
id: 4515C308-F248-11E8-B48F-1D18A9856A87
last_name: Merrin
orcid: 0000-0001-5145-4609
- first_name: Maksym
full_name: Serbyn, Maksym
id: 47809E7E-F248-11E8-B48F-1D18A9856A87
last_name: Serbyn
orcid: 0000-0002-2399-5827
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
citation:
ama: 'Choueiri GH, Suri B, Merrin J, Serbyn M, Hof B, Budanur NB. Crises and chaotic
scattering in hydrodynamic pilot-wave experiments. Chaos: An Interdisciplinary
Journal of Nonlinear Science. 2022;32(9). doi:10.1063/5.0102904'
apa: 'Choueiri, G. H., Suri, B., Merrin, J., Serbyn, M., Hof, B., & Budanur,
N. B. (2022). Crises and chaotic scattering in hydrodynamic pilot-wave experiments.
Chaos: An Interdisciplinary Journal of Nonlinear Science. AIP Publishing.
https://doi.org/10.1063/5.0102904'
chicago: 'Choueiri, George H, Balachandra Suri, Jack Merrin, Maksym Serbyn, Björn
Hof, and Nazmi B Budanur. “Crises and Chaotic Scattering in Hydrodynamic Pilot-Wave
Experiments.” Chaos: An Interdisciplinary Journal of Nonlinear Science.
AIP Publishing, 2022. https://doi.org/10.1063/5.0102904.'
ieee: 'G. H. Choueiri, B. Suri, J. Merrin, M. Serbyn, B. Hof, and N. B. Budanur,
“Crises and chaotic scattering in hydrodynamic pilot-wave experiments,” Chaos:
An Interdisciplinary Journal of Nonlinear Science, vol. 32, no. 9. AIP Publishing,
2022.'
ista: 'Choueiri GH, Suri B, Merrin J, Serbyn M, Hof B, Budanur NB. 2022. Crises
and chaotic scattering in hydrodynamic pilot-wave experiments. Chaos: An Interdisciplinary
Journal of Nonlinear Science. 32(9), 093138.'
mla: 'Choueiri, George H., et al. “Crises and Chaotic Scattering in Hydrodynamic
Pilot-Wave Experiments.” Chaos: An Interdisciplinary Journal of Nonlinear Science,
vol. 32, no. 9, 093138, AIP Publishing, 2022, doi:10.1063/5.0102904.'
short: 'G.H. Choueiri, B. Suri, J. Merrin, M. Serbyn, B. Hof, N.B. Budanur, Chaos:
An Interdisciplinary Journal of Nonlinear Science 32 (2022).'
date_created: 2023-01-16T09:58:16Z
date_published: 2022-09-26T00:00:00Z
date_updated: 2023-08-04T09:51:17Z
day: '26'
ddc:
- '530'
department:
- _id: MaSe
- _id: BjHo
- _id: NanoFab
doi: 10.1063/5.0102904
external_id:
arxiv:
- '2206.01531'
isi:
- '000861009600005'
file:
- access_level: open_access
checksum: 17881eff8b21969359a2dd64620120ba
content_type: application/pdf
creator: dernst
date_created: 2023-01-30T09:41:12Z
date_updated: 2023-01-30T09:41:12Z
file_id: '12445'
file_name: 2022_Chaos_Choueiri.pdf
file_size: 3209644
relation: main_file
success: 1
file_date_updated: 2023-01-30T09:41:12Z
has_accepted_license: '1'
intvolume: ' 32'
isi: 1
issue: '9'
keyword:
- Applied Mathematics
- General Physics and Astronomy
- Mathematical Physics
- Statistical and Nonlinear Physics
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
publication: 'Chaos: An Interdisciplinary Journal of Nonlinear Science'
publication_identifier:
eissn:
- 1089-7682
issn:
- 1054-1500
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: Crises and chaotic scattering in hydrodynamic pilot-wave experiments
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 32
year: '2022'
...
---
_id: '12279'
abstract:
- lang: eng
text: We report frictional drag reduction and a complete flow relaminarization of
elastic turbulence (ET) at vanishing inertia in a viscoelastic channel flow past
an obstacle. We show that the intensity of the observed elastic waves and wall-normal
vorticity correlate well with the measured drag above the onset of ET. Moreover,
we find that the elastic wave frequency grows with the Weissenberg number, and
at sufficiently high frequency it causes a decay of the elastic waves, resulting
in ET attenuation and drag reduction. Thus, this allows us to substantiate a physical
mechanism, involving the interaction of elastic waves with wall-normal vorticity
fluctuations, leading to the drag reduction and relaminarization phenomena at
low Reynolds number.
acknowledgement: "We thank G. Falkovich for discussion and Guy Han for technical support.
We are grateful to N. Jha for his help in µPIV measurements. This work is partially
supported by the grants from\r\nIsrael Science Foundation (ISF; grant #882/15 and
grant #784/19) and Binational USA-Israel Foundation (BSF;grant #2016145). "
article_number: L081301
article_processing_charge: No
article_type: original
author:
- first_name: M. Vijay
full_name: Kumar, M. Vijay
last_name: Kumar
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
- first_name: Dongyang
full_name: Li, Dongyang
last_name: Li
- first_name: Victor
full_name: Steinberg, Victor
last_name: Steinberg
citation:
ama: Kumar MV, Varshney A, Li D, Steinberg V. Relaminarization of elastic turbulence.
Physical Review Fluids. 2022;7(8). doi:10.1103/physrevfluids.7.l081301
apa: Kumar, M. V., Varshney, A., Li, D., & Steinberg, V. (2022). Relaminarization
of elastic turbulence. Physical Review Fluids. American Physical Society.
https://doi.org/10.1103/physrevfluids.7.l081301
chicago: Kumar, M. Vijay, Atul Varshney, Dongyang Li, and Victor Steinberg. “Relaminarization
of Elastic Turbulence.” Physical Review Fluids. American Physical Society,
2022. https://doi.org/10.1103/physrevfluids.7.l081301.
ieee: M. V. Kumar, A. Varshney, D. Li, and V. Steinberg, “Relaminarization of elastic
turbulence,” Physical Review Fluids, vol. 7, no. 8. American Physical Society,
2022.
ista: Kumar MV, Varshney A, Li D, Steinberg V. 2022. Relaminarization of elastic
turbulence. Physical Review Fluids. 7(8), L081301.
mla: Kumar, M. Vijay, et al. “Relaminarization of Elastic Turbulence.” Physical
Review Fluids, vol. 7, no. 8, L081301, American Physical Society, 2022, doi:10.1103/physrevfluids.7.l081301.
short: M.V. Kumar, A. Varshney, D. Li, V. Steinberg, Physical Review Fluids 7 (2022).
date_created: 2023-01-16T10:02:40Z
date_published: 2022-08-03T00:00:00Z
date_updated: 2023-08-04T10:26:40Z
day: '03'
department:
- _id: BjHo
doi: 10.1103/physrevfluids.7.l081301
external_id:
arxiv:
- '2205.12871'
isi:
- '000836397000001'
intvolume: ' 7'
isi: 1
issue: '8'
keyword:
- Fluid Flow and Transfer Processes
- Modeling and Simulation
- Computational Mechanics
language:
- iso: eng
main_file_link:
- open_access: '1'
url: ' https://doi.org/10.48550/arXiv.2205.12871'
month: '08'
oa: 1
oa_version: Preprint
publication: Physical Review Fluids
publication_identifier:
issn:
- 2469-990X
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Relaminarization of elastic turbulence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 7
year: '2022'
...
---
_id: '12146'
abstract:
- lang: eng
text: 'In this paper, we explore the stability and dynamical relevance of a wide
variety of steady, time-periodic, quasiperiodic, and chaotic flows arising between
orthogonally stretching parallel plates. We first explore the stability of all
the steady flow solution families formerly identified by Ayats et al. [“Flows
between orthogonally stretching parallel plates,” Phys. Fluids 33, 024103 (2021)],
concluding that only the one that originates from the Stokesian approximation
is actually stable. When both plates are shrinking at identical or nearly the
same deceleration rates, this Stokesian flow exhibits a Hopf bifurcation that
leads to stable time-periodic regimes. The resulting time-periodic orbits or flows
are tracked for different Reynolds numbers and stretching rates while monitoring
their Floquet exponents to identify secondary instabilities. It is found that
these time-periodic flows also exhibit Neimark–Sacker bifurcations, generating
stable quasiperiodic flows (tori) that may sometimes give rise to chaotic dynamics
through a Ruelle–Takens–Newhouse scenario. However, chaotic dynamics is unusually
observed, as the quasiperiodic flows generally become phase-locked through a resonance
mechanism before a strange attractor may arise, thus restoring the time-periodicity
of the flow. In this work, we have identified and tracked four different resonance
regions, also known as Arnold tongues or horns. In particular, the 1 : 4 strong
resonance region is explored in great detail, where the identified scenarios are
in very good agreement with normal form theory. '
acknowledgement: "This work was supported by the Spanish MINECO under Grant Nos. FIS2017-85794-P
and PRX18/00179, the Spanish MICINN through Grant No. PID2020-114043GB-I00, and
the\r\nGeneralitat de Catalunya under Grant No. 2017-SGR-785. B.W.’s research was
also supported by the Chinese Scholarship Council through Grant CSC No. 201806440152."
article_number: '114111'
article_processing_charge: No
article_type: original
author:
- first_name: B.
full_name: Wang, B.
last_name: Wang
- first_name: Roger
full_name: Ayats López, Roger
id: ab77522d-073b-11ed-8aff-e71b39258362
last_name: Ayats López
orcid: 0000-0001-6572-0621
- first_name: A.
full_name: Meseguer, A.
last_name: Meseguer
- first_name: F.
full_name: Marques, F.
last_name: Marques
citation:
ama: Wang B, Ayats López R, Meseguer A, Marques F. Phase-locking flows between orthogonally
stretching parallel plates. Physics of Fluids. 2022;34(11). doi:10.1063/5.0124152
apa: Wang, B., Ayats López, R., Meseguer, A., & Marques, F. (2022). Phase-locking
flows between orthogonally stretching parallel plates. Physics of Fluids.
AIP Publishing. https://doi.org/10.1063/5.0124152
chicago: Wang, B., Roger Ayats López, A. Meseguer, and F. Marques. “Phase-Locking
Flows between Orthogonally Stretching Parallel Plates.” Physics of Fluids.
AIP Publishing, 2022. https://doi.org/10.1063/5.0124152.
ieee: B. Wang, R. Ayats López, A. Meseguer, and F. Marques, “Phase-locking flows
between orthogonally stretching parallel plates,” Physics of Fluids, vol.
34, no. 11. AIP Publishing, 2022.
ista: Wang B, Ayats López R, Meseguer A, Marques F. 2022. Phase-locking flows between
orthogonally stretching parallel plates. Physics of Fluids. 34(11), 114111.
mla: Wang, B., et al. “Phase-Locking Flows between Orthogonally Stretching Parallel
Plates.” Physics of Fluids, vol. 34, no. 11, 114111, AIP Publishing, 2022,
doi:10.1063/5.0124152.
short: B. Wang, R. Ayats López, A. Meseguer, F. Marques, Physics of Fluids 34 (2022).
date_created: 2023-01-12T12:06:58Z
date_published: 2022-11-04T00:00:00Z
date_updated: 2023-10-03T11:07:58Z
day: '04'
department:
- _id: BjHo
doi: 10.1063/5.0124152
external_id:
isi:
- '000880665300024'
intvolume: ' 34'
isi: 1
issue: '11'
keyword:
- Condensed Matter Physics
- Fluid Flow and Transfer Processes
- Mechanics of Materials
- Computational Mechanics
- Mechanical Engineering
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://upcommons.upc.edu/handle/2117/385635
month: '11'
oa: 1
oa_version: Submitted Version
publication: Physics of Fluids
publication_identifier:
eissn:
- 1089-7666
issn:
- 1070-6631
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: Phase-locking flows between orthogonally stretching parallel plates
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 34
year: '2022'
...
---
_id: '10791'
abstract:
- lang: eng
text: The mammalian neocortex is composed of diverse neuronal and glial cell classes
that broadly arrange in six distinct laminae. Cortical layers emerge during development
and defects in the developmental programs that orchestrate cortical lamination
are associated with neurodevelopmental diseases. The developmental principle of
cortical layer formation depends on concerted radial projection neuron migration,
from their birthplace to their final target position. Radial migration occurs
in defined sequential steps, regulated by a large array of signaling pathways.
However, based on genetic loss-of-function experiments, most studies have thus
far focused on the role of cell-autonomous gene function. Yet, cortical neuron
migration in situ is a complex process and migrating neurons traverse along diverse
cellular compartments and environments. The role of tissue-wide properties and
genetic state in radial neuron migration is however not clear. Here we utilized
mosaic analysis with double markers (MADM) technology to either sparsely or globally
delete gene function, followed by quantitative single-cell phenotyping. The MADM-based
gene ablation paradigms in combination with computational modeling demonstrated
that global tissue-wide effects predominate cell-autonomous gene function albeit
in a gene-specific manner. Our results thus suggest that the genetic landscape
in a tissue critically affects the overall migration phenotype of individual cortical
projection neurons. In a broader context, our findings imply that global tissue-wide
effects represent an essential component of the underlying etiology associated
with focal malformations of cortical development in particular, and neurological
diseases in general.
acknowledged_ssus:
- _id: LifeSc
- _id: PreCl
- _id: Bio
acknowledgement: "A.H.H. was a recipient of a DOC Fellowship (24812) of the Austrian
Academy of Sciences. This work also received support from IST Austria institutional
funds; the People Programme (Marie Curie Actions) of the European Union’s Seventh
Framework Programme (FP7/2007–2013) under REA grant agreement No 618444 to S.H.\r\nAPC
funding was obtained by IST Austria institutional funds.\r\nWe thank A. Sommer and
C. Czepe (VBCF GmbH, NGS Unit), L. Andersen, J. Sonntag and J. Renno for technical
support and/or initial experiments; M. Sixt, J. Nimpf and all members of the Hippenmeyer
lab for discussion. This research was supported by the Scientific Service Units
of IST Austria through resources provided by the Imaging and Optics Facility, Lab
Support Facility and Preclinical Facility."
article_number: kvac009
article_processing_charge: No
article_type: original
author:
- first_name: Andi H
full_name: Hansen, Andi H
id: 38853E16-F248-11E8-B48F-1D18A9856A87
last_name: Hansen
- first_name: Florian
full_name: Pauler, Florian
id: 48EA0138-F248-11E8-B48F-1D18A9856A87
last_name: Pauler
orcid: 0000-0002-7462-0048
- first_name: Michael
full_name: Riedl, Michael
id: 3BE60946-F248-11E8-B48F-1D18A9856A87
last_name: Riedl
orcid: 0000-0003-4844-6311
- first_name: Carmen
full_name: Streicher, Carmen
id: 36BCB99C-F248-11E8-B48F-1D18A9856A87
last_name: Streicher
- first_name: Anna-Magdalena
full_name: Heger, Anna-Magdalena
id: 4B76FFD2-F248-11E8-B48F-1D18A9856A87
last_name: Heger
- first_name: Susanne
full_name: Laukoter, Susanne
id: 2D6B7A9A-F248-11E8-B48F-1D18A9856A87
last_name: Laukoter
orcid: 0000-0002-7903-3010
- first_name: Christoph M
full_name: Sommer, Christoph M
id: 4DF26D8C-F248-11E8-B48F-1D18A9856A87
last_name: Sommer
orcid: 0000-0003-1216-9105
- first_name: Armel
full_name: Nicolas, Armel
id: 2A103192-F248-11E8-B48F-1D18A9856A87
last_name: Nicolas
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
- first_name: Li Huei
full_name: Tsai, Li Huei
last_name: Tsai
- first_name: Thomas
full_name: Rülicke, Thomas
last_name: Rülicke
- first_name: Simon
full_name: Hippenmeyer, Simon
id: 37B36620-F248-11E8-B48F-1D18A9856A87
last_name: Hippenmeyer
orcid: 0000-0003-2279-1061
citation:
ama: Hansen AH, Pauler F, Riedl M, et al. Tissue-wide effects override cell-intrinsic
gene function in radial neuron migration. Oxford Open Neuroscience. 2022;1(1).
doi:10.1093/oons/kvac009
apa: Hansen, A. H., Pauler, F., Riedl, M., Streicher, C., Heger, A.-M., Laukoter,
S., … Hippenmeyer, S. (2022). Tissue-wide effects override cell-intrinsic gene
function in radial neuron migration. Oxford Open Neuroscience. Oxford Academic.
https://doi.org/10.1093/oons/kvac009
chicago: Hansen, Andi H, Florian Pauler, Michael Riedl, Carmen Streicher, Anna-Magdalena
Heger, Susanne Laukoter, Christoph M Sommer, et al. “Tissue-Wide Effects Override
Cell-Intrinsic Gene Function in Radial Neuron Migration.” Oxford Open Neuroscience.
Oxford Academic, 2022. https://doi.org/10.1093/oons/kvac009.
ieee: A. H. Hansen et al., “Tissue-wide effects override cell-intrinsic gene
function in radial neuron migration,” Oxford Open Neuroscience, vol. 1,
no. 1. Oxford Academic, 2022.
ista: Hansen AH, Pauler F, Riedl M, Streicher C, Heger A-M, Laukoter S, Sommer CM,
Nicolas A, Hof B, Tsai LH, Rülicke T, Hippenmeyer S. 2022. Tissue-wide effects
override cell-intrinsic gene function in radial neuron migration. Oxford Open
Neuroscience. 1(1), kvac009.
mla: Hansen, Andi H., et al. “Tissue-Wide Effects Override Cell-Intrinsic Gene Function
in Radial Neuron Migration.” Oxford Open Neuroscience, vol. 1, no. 1, kvac009,
Oxford Academic, 2022, doi:10.1093/oons/kvac009.
short: A.H. Hansen, F. Pauler, M. Riedl, C. Streicher, A.-M. Heger, S. Laukoter,
C.M. Sommer, A. Nicolas, B. Hof, L.H. Tsai, T. Rülicke, S. Hippenmeyer, Oxford
Open Neuroscience 1 (2022).
date_created: 2022-02-25T07:52:11Z
date_published: 2022-07-07T00:00:00Z
date_updated: 2023-11-30T10:55:12Z
day: '07'
ddc:
- '570'
department:
- _id: SiHi
- _id: BjHo
- _id: LifeSc
- _id: EM-Fac
doi: 10.1093/oons/kvac009
ec_funded: 1
file:
- access_level: open_access
checksum: 822e76e056c07099d1fb27d1ece5941b
content_type: application/pdf
creator: dernst
date_created: 2023-08-16T08:00:30Z
date_updated: 2023-08-16T08:00:30Z
file_id: '14061'
file_name: 2023_OxfordOpenNeuroscience_Hansen.pdf
file_size: 4846551
relation: main_file
success: 1
file_date_updated: 2023-08-16T08:00:30Z
has_accepted_license: '1'
intvolume: ' 1'
issue: '1'
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
project:
- _id: 25D61E48-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '618444'
name: Molecular Mechanisms of Cerebral Cortex Development
- _id: 2625A13E-B435-11E9-9278-68D0E5697425
grant_number: '24812'
name: Molecular Mechanisms of Radial Neuronal Migration
publication: Oxford Open Neuroscience
publication_identifier:
eissn:
- 2753-149X
publication_status: published
publisher: Oxford Academic
quality_controlled: '1'
related_material:
record:
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status: public
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relation: dissertation_contains
status: public
status: public
title: Tissue-wide effects override cell-intrinsic gene function in radial neuron
migration
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 1
year: '2022'
...
---
_id: '10703'
abstract:
- lang: eng
text: 'When crawling through the body, leukocytes often traverse tissues that are
densely packed with extracellular matrix and other cells, and this raises the
question: How do leukocytes overcome compressive mechanical loads? Here, we show
that the actin cortex of leukocytes is mechanoresponsive and that this responsiveness
requires neither force sensing via the nucleus nor adhesive interactions with
a substrate. Upon global compression of the cell body as well as local indentation
of the plasma membrane, Wiskott-Aldrich syndrome protein (WASp) assembles into
dot-like structures, providing activation platforms for Arp2/3 nucleated actin
patches. These patches locally push against the external load, which can be obstructing
collagen fibers or other cells, and thereby create space to facilitate forward
locomotion. We show in vitro and in vivo that this WASp function is rate limiting
for ameboid leukocyte migration in dense but not in loose environments and is
required for trafficking through diverse tissues such as skin and lymph nodes.'
acknowledged_ssus:
- _id: LifeSc
- _id: Bio
- _id: EM-Fac
acknowledgement: We thank N. Darwish-Miranda, F. Leite, F.P. Assen, and A. Eichner
for advice and help with experiments. We thank J. Renkawitz, E. Kiermaier, A. Juanes
Garcia, and M. Avellaneda for critical reading of the manuscript. We thank M. Driscoll
for advice on fluorescent labeling of collagen gels. This research was supported
by the Scientific Service Units (SSUs) of IST Austria through resources provided
by Molecular Biology Services/Lab Support Facility (LSF)/Bioimaging Facility/Electron
Microscopy Facility. This work was funded by grants from the European Research Council
( CoG 724373 ) and the Austrian Science Foundation (FWF) to M.S. F.G. received funding
from the European Union’s Horizon 2020 research and innovation program under the
Marie Skłodowska-Curie grant agreement no. 747687.
article_processing_charge: No
article_type: original
author:
- first_name: Florian
full_name: Gaertner, Florian
last_name: Gaertner
- first_name: Patricia
full_name: Reis-Rodrigues, Patricia
last_name: Reis-Rodrigues
- first_name: Ingrid
full_name: De Vries, Ingrid
id: 4C7D837E-F248-11E8-B48F-1D18A9856A87
last_name: De Vries
- first_name: Miroslav
full_name: Hons, Miroslav
id: 4167FE56-F248-11E8-B48F-1D18A9856A87
last_name: Hons
orcid: 0000-0002-6625-3348
- first_name: Juan
full_name: Aguilera, Juan
last_name: Aguilera
- first_name: Michael
full_name: Riedl, Michael
id: 3BE60946-F248-11E8-B48F-1D18A9856A87
last_name: Riedl
orcid: 0000-0003-4844-6311
- first_name: Alexander F
full_name: Leithner, Alexander F
id: 3B1B77E4-F248-11E8-B48F-1D18A9856A87
last_name: Leithner
orcid: 0000-0002-1073-744X
- first_name: Saren
full_name: Tasciyan, Saren
id: 4323B49C-F248-11E8-B48F-1D18A9856A87
last_name: Tasciyan
orcid: 0000-0003-1671-393X
- first_name: Aglaja
full_name: Kopf, Aglaja
id: 31DAC7B6-F248-11E8-B48F-1D18A9856A87
last_name: Kopf
orcid: 0000-0002-2187-6656
- first_name: Jack
full_name: Merrin, Jack
id: 4515C308-F248-11E8-B48F-1D18A9856A87
last_name: Merrin
orcid: 0000-0001-5145-4609
- first_name: Vanessa
full_name: Zheden, Vanessa
id: 39C5A68A-F248-11E8-B48F-1D18A9856A87
last_name: Zheden
orcid: 0000-0002-9438-4783
- first_name: Walter
full_name: Kaufmann, Walter
id: 3F99E422-F248-11E8-B48F-1D18A9856A87
last_name: Kaufmann
orcid: 0000-0001-9735-5315
- first_name: Robert
full_name: Hauschild, Robert
id: 4E01D6B4-F248-11E8-B48F-1D18A9856A87
last_name: Hauschild
orcid: 0000-0001-9843-3522
- first_name: Michael K
full_name: Sixt, Michael K
id: 41E9FBEA-F248-11E8-B48F-1D18A9856A87
last_name: Sixt
orcid: 0000-0002-6620-9179
citation:
ama: Gaertner F, Reis-Rodrigues P, de Vries I, et al. WASp triggers mechanosensitive
actin patches to facilitate immune cell migration in dense tissues. Developmental
Cell. 2022;57(1):47-62.e9. doi:10.1016/j.devcel.2021.11.024
apa: Gaertner, F., Reis-Rodrigues, P., de Vries, I., Hons, M., Aguilera, J., Riedl,
M., … Sixt, M. K. (2022). WASp triggers mechanosensitive actin patches to facilitate
immune cell migration in dense tissues. Developmental Cell. Cell Press ;
Elsevier. https://doi.org/10.1016/j.devcel.2021.11.024
chicago: Gaertner, Florian, Patricia Reis-Rodrigues, Ingrid de Vries, Miroslav Hons,
Juan Aguilera, Michael Riedl, Alexander F Leithner, et al. “WASp Triggers Mechanosensitive
Actin Patches to Facilitate Immune Cell Migration in Dense Tissues.” Developmental
Cell. Cell Press ; Elsevier, 2022. https://doi.org/10.1016/j.devcel.2021.11.024.
ieee: F. Gaertner et al., “WASp triggers mechanosensitive actin patches to
facilitate immune cell migration in dense tissues,” Developmental Cell,
vol. 57, no. 1. Cell Press ; Elsevier, p. 47–62.e9, 2022.
ista: Gaertner F, Reis-Rodrigues P, de Vries I, Hons M, Aguilera J, Riedl M, Leithner
AF, Tasciyan S, Kopf A, Merrin J, Zheden V, Kaufmann W, Hauschild R, Sixt MK.
2022. WASp triggers mechanosensitive actin patches to facilitate immune cell migration
in dense tissues. Developmental Cell. 57(1), 47–62.e9.
mla: Gaertner, Florian, et al. “WASp Triggers Mechanosensitive Actin Patches to
Facilitate Immune Cell Migration in Dense Tissues.” Developmental Cell,
vol. 57, no. 1, Cell Press ; Elsevier, 2022, p. 47–62.e9, doi:10.1016/j.devcel.2021.11.024.
short: F. Gaertner, P. Reis-Rodrigues, I. de Vries, M. Hons, J. Aguilera, M. Riedl,
A.F. Leithner, S. Tasciyan, A. Kopf, J. Merrin, V. Zheden, W. Kaufmann, R. Hauschild,
M.K. Sixt, Developmental Cell 57 (2022) 47–62.e9.
date_created: 2022-01-30T23:01:33Z
date_published: 2022-01-10T00:00:00Z
date_updated: 2024-03-28T23:30:23Z
day: '10'
ddc:
- '570'
department:
- _id: MiSi
- _id: EM-Fac
- _id: NanoFab
- _id: BjHo
doi: 10.1016/j.devcel.2021.11.024
ec_funded: 1
external_id:
isi:
- '000768933800005'
pmid:
- '34919802'
intvolume: ' 57'
isi: 1
issue: '1'
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-nd/4.0/
main_file_link:
- open_access: '1'
url: https://www.sciencedirect.com/science/article/pii/S1534580721009497
month: '01'
oa: 1
oa_version: Published Version
page: 47-62.e9
pmid: 1
project:
- _id: 260AA4E2-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '747687'
name: Mechanical Adaptation of Lamellipodial Actin Networks in Migrating Cells
- _id: 25FE9508-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '724373'
name: Cellular navigation along spatial gradients
publication: Developmental Cell
publication_identifier:
eissn:
- 1878-1551
issn:
- 1534-5807
publication_status: published
publisher: Cell Press ; Elsevier
quality_controlled: '1'
related_material:
record:
- id: '12726'
relation: dissertation_contains
status: public
- id: '14530'
relation: dissertation_contains
status: public
- id: '12401'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: WASp triggers mechanosensitive actin patches to facilitate immune cell migration
in dense tissues
tmp:
image: /images/cc_by_nc_nd.png
legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
(CC BY-NC-ND 4.0)
short: CC BY-NC-ND (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 57
year: '2022'
...
---
_id: '8999'
abstract:
- lang: eng
text: "In many basic shear flows, such as pipe, Couette, and channel flow, turbulence
does not\r\narise from an instability of the laminar state, and both dynamical
states co-exist. With decreasing flow speed (i.e., decreasing Reynolds number)
the fraction of fluid in laminar motion increases while turbulence recedes and
eventually the entire flow relaminarizes. The first step towards understanding
the nature of this transition is to determine if the phase change is of either
first or second order. In the former case, the turbulent fraction would drop discontinuously
to zero as the Reynolds number decreases while in the latter the process would
be continuous. For Couette flow, the flow between two parallel plates, earlier
studies suggest a discontinuous scenario. In the present study we realize a Couette
flow between two concentric cylinders which allows studies to be carried out in
large aspect ratios and for extensive observation times. The presented measurements
show that the transition in this circular Couette geometry is continuous suggesting
that former studies were limited by finite size effects. A further characterization
of this transition, in particular its relation to the directed percolation universality
class, requires even larger system sizes than presently available. "
acknowledgement: "This research was funded by the Central Research Development Fund
of the University of\r\nBremen grant number ZF04B /2019/FB04 Avila_Kerstin (“Independent
Project for Postdocs”). Shreyas Jalikop is acknowledged for recording some of the
lifetime measurements\r\n"
article_number: '58'
article_processing_charge: No
article_type: original
author:
- first_name: Kerstin
full_name: Avila, Kerstin
id: fcf74381-53e1-11eb-a6dc-b0e2acf78757
last_name: Avila
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Avila K, Hof B. Second-order phase transition in counter-rotating taylor-couette
flow experiment. Entropy. 2021;23(1). doi:10.3390/e23010058
apa: Avila, K., & Hof, B. (2021). Second-order phase transition in counter-rotating
taylor-couette flow experiment. Entropy. MDPI. https://doi.org/10.3390/e23010058
chicago: Avila, Kerstin, and Björn Hof. “Second-Order Phase Transition in Counter-Rotating
Taylor-Couette Flow Experiment.” Entropy. MDPI, 2021. https://doi.org/10.3390/e23010058.
ieee: K. Avila and B. Hof, “Second-order phase transition in counter-rotating taylor-couette
flow experiment,” Entropy, vol. 23, no. 1. MDPI, 2021.
ista: Avila K, Hof B. 2021. Second-order phase transition in counter-rotating taylor-couette
flow experiment. Entropy. 23(1), 58.
mla: Avila, Kerstin, and Björn Hof. “Second-Order Phase Transition in Counter-Rotating
Taylor-Couette Flow Experiment.” Entropy, vol. 23, no. 1, 58, MDPI, 2021,
doi:10.3390/e23010058.
short: K. Avila, B. Hof, Entropy 23 (2021).
date_created: 2021-01-10T23:01:17Z
date_published: 2021-01-01T00:00:00Z
date_updated: 2023-08-07T13:31:07Z
day: '01'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.3390/e23010058
external_id:
isi:
- '000610135400001'
pmid:
- '33396499'
file:
- access_level: open_access
checksum: 3ba3dd8b7eecff713b72c5e9ba30d626
content_type: application/pdf
creator: dernst
date_created: 2021-01-11T07:50:32Z
date_updated: 2021-01-11T07:50:32Z
file_id: '9003'
file_name: 2021_Entropy_Avila.pdf
file_size: 9456389
relation: main_file
success: 1
file_date_updated: 2021-01-11T07:50:32Z
has_accepted_license: '1'
intvolume: ' 23'
isi: 1
issue: '1'
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
pmid: 1
publication: Entropy
publication_identifier:
eissn:
- 1099-4300
publication_status: published
publisher: MDPI
quality_controlled: '1'
scopus_import: '1'
status: public
title: Second-order phase transition in counter-rotating taylor-couette flow experiment
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 23
year: '2021'
...
---
_id: '9207'
abstract:
- lang: eng
text: "In this paper we experimentally study the transitional range of Reynolds
numbers in\r\nplane Couette–Poiseuille flow, focusing our attention on the localized
turbulent structures\r\ntriggered by a strong impulsive jet and the large-scale
flow generated around these\r\nstructures. We present a detailed investigation
of the large-scale flow and show how\r\nits amplitude depends on Reynolds number
and amplitude perturbation. In addition,\r\nwe characterize the initial dynamics
of the localized turbulent spot, which includes the\r\ncoupling between the small
and large scales, as well as the dependence of the advection\r\nspeed on the large-scale
flow generated around the spot. Finally, we provide the first\r\nexperimental
measurements of the large-scale flow around an oblique turbulent band."
acknowledgement: "We thank Y. Duguet, S. Gomé, G. Lemoult, T. Liu, B. Semin and L.S.
Tuckerman for\r\nfruitful discussions. \r\nThis work was supported by a grant, TRANSFLOW,
provided by the Agence Nationale de\r\nla Recherche (ANR). A.M.P. was partially
supported by the French Embassy in Russia (I.I. Mechnikov scholarship) and by the
Russian Science Foundation (project no. 18-79-00189). L.K. was partially supported
by the European Union’s Horizon 2020 research and innovation programme under the
Marie Skłodowska-Curie grant agreement no. 754411."
article_number: A24
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Lukasz
full_name: Klotz, Lukasz
id: 2C9AF1C2-F248-11E8-B48F-1D18A9856A87
last_name: Klotz
orcid: 0000-0003-1740-7635
- first_name: A. M.
full_name: Pavlenko, A. M.
last_name: Pavlenko
- first_name: J. E.
full_name: Wesfreid, J. E.
last_name: Wesfreid
citation:
ama: 'Klotz L, Pavlenko AM, Wesfreid JE. Experimental measurements in plane Couette-Poiseuille
flow: Dynamics of the large- and small-scale flow. Journal of Fluid Mechanics.
2021;912. doi:10.1017/jfm.2020.1089'
apa: 'Klotz, L., Pavlenko, A. M., & Wesfreid, J. E. (2021). Experimental measurements
in plane Couette-Poiseuille flow: Dynamics of the large- and small-scale flow.
Journal of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2020.1089'
chicago: 'Klotz, Lukasz, A. M. Pavlenko, and J. E. Wesfreid. “Experimental Measurements
in Plane Couette-Poiseuille Flow: Dynamics of the Large- and Small-Scale Flow.”
Journal of Fluid Mechanics. Cambridge University Press, 2021. https://doi.org/10.1017/jfm.2020.1089.'
ieee: 'L. Klotz, A. M. Pavlenko, and J. E. Wesfreid, “Experimental measurements
in plane Couette-Poiseuille flow: Dynamics of the large- and small-scale flow,”
Journal of Fluid Mechanics, vol. 912. Cambridge University Press, 2021.'
ista: 'Klotz L, Pavlenko AM, Wesfreid JE. 2021. Experimental measurements in plane
Couette-Poiseuille flow: Dynamics of the large- and small-scale flow. Journal
of Fluid Mechanics. 912, A24.'
mla: 'Klotz, Lukasz, et al. “Experimental Measurements in Plane Couette-Poiseuille
Flow: Dynamics of the Large- and Small-Scale Flow.” Journal of Fluid Mechanics,
vol. 912, A24, Cambridge University Press, 2021, doi:10.1017/jfm.2020.1089.'
short: L. Klotz, A.M. Pavlenko, J.E. Wesfreid, Journal of Fluid Mechanics 912 (2021).
date_created: 2021-02-28T23:01:25Z
date_published: 2021-02-15T00:00:00Z
date_updated: 2023-08-07T13:55:40Z
day: '15'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2020.1089
ec_funded: 1
external_id:
isi:
- '000618034400001'
file:
- access_level: open_access
checksum: b8020d6338667673e34fde0608913dd2
content_type: application/pdf
creator: dernst
date_created: 2021-03-03T09:49:34Z
date_updated: 2021-03-03T09:49:34Z
file_id: '9220'
file_name: 2021_JourFluidMechanics_Klotz.pdf
file_size: 4124471
relation: main_file
success: 1
file_date_updated: 2021-03-03T09:49:34Z
has_accepted_license: '1'
intvolume: ' 912'
isi: 1
language:
- iso: eng
month: '02'
oa: 1
oa_version: Published Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Experimental measurements in plane Couette-Poiseuille flow: Dynamics of the
large- and small-scale flow'
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 912
year: '2021'
...
---
_id: '9297'
abstract:
- lang: eng
text: 'We report the results of an experimental investigation into the decay of
turbulence in plane Couette–Poiseuille flow using ‘quench’ experiments where the
flow laminarises after a sudden reduction in Reynolds number Re. Specifically,
we study the velocity field in the streamwise–spanwise plane. We show that the
spanwise velocity containing rolls decays faster than the streamwise velocity,
which displays elongated regions of higher or lower velocity called streaks. At
final Reynolds numbers above 425, the decay of streaks displays two stages: first
a slow decay when rolls are present and secondly a more rapid decay of streaks
alone. The difference in behaviour results from the regeneration of streaks by
rolls, called the lift-up effect. We define the turbulent fraction as the portion
of the flow containing turbulence and this is estimated by thresholding the spanwise
velocity component. It decreases linearly with time in the whole range of final
Re. The corresponding decay slope increases linearly with final Re. The extrapolated
value at which this decay slope vanishes is Reaz≈656±10, close to Reg≈670 at which
turbulence is self-sustained. The decay of the energy computed from the spanwise
velocity component is found to be exponential. The corresponding decay rate increases
linearly with Re, with an extrapolated vanishing value at ReAz≈688±10. This value
is also close to the value at which the turbulence is self-sustained, showing
that valuable information on the transition can be obtained over a wide range
of Re.'
acknowledgement: "We gratefully acknowledge Joran Rolland, Yohann Duguet, Romain Monchaux,
S´ebastien Gom´e, Laurette Tuckerman, Dwight Barkley, Olivier Dauchot and Sabine
Bottin for fruitful discussions. We thank Xavier Benoit-Gonin, Amaury Fourgeaud,
Thierry Darnige, Olivier Brouard and Justine Laurent for technical help. This work
has benefited from the ANR TransFlow, and by starting grants obtained by B.S. from
CNRS (INSIS) and ESPCI. T.M. was\r\nsupported by a Joliot visiting professorship
grant from ESPCI."
article_number: A65
article_processing_charge: No
article_type: original
author:
- first_name: T.
full_name: Liu, T.
last_name: Liu
- first_name: B.
full_name: Semin, B.
last_name: Semin
- first_name: Lukasz
full_name: Klotz, Lukasz
id: 2C9AF1C2-F248-11E8-B48F-1D18A9856A87
last_name: Klotz
orcid: 0000-0003-1740-7635
- first_name: R.
full_name: Godoy-Diana, R.
last_name: Godoy-Diana
- first_name: J. E.
full_name: Wesfreid, J. E.
last_name: Wesfreid
- first_name: T.
full_name: Mullin, T.
last_name: Mullin
citation:
ama: Liu T, Semin B, Klotz L, Godoy-Diana R, Wesfreid JE, Mullin T. Decay of streaks
and rolls in plane Couette-Poiseuille flow. Journal of Fluid Mechanics.
2021;915. doi:10.1017/jfm.2021.89
apa: Liu, T., Semin, B., Klotz, L., Godoy-Diana, R., Wesfreid, J. E., & Mullin,
T. (2021). Decay of streaks and rolls in plane Couette-Poiseuille flow. Journal
of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2021.89
chicago: Liu, T., B. Semin, Lukasz Klotz, R. Godoy-Diana, J. E. Wesfreid, and T.
Mullin. “Decay of Streaks and Rolls in Plane Couette-Poiseuille Flow.” Journal
of Fluid Mechanics. Cambridge University Press, 2021. https://doi.org/10.1017/jfm.2021.89.
ieee: T. Liu, B. Semin, L. Klotz, R. Godoy-Diana, J. E. Wesfreid, and T. Mullin,
“Decay of streaks and rolls in plane Couette-Poiseuille flow,” Journal of Fluid
Mechanics, vol. 915. Cambridge University Press, 2021.
ista: Liu T, Semin B, Klotz L, Godoy-Diana R, Wesfreid JE, Mullin T. 2021. Decay
of streaks and rolls in plane Couette-Poiseuille flow. Journal of Fluid Mechanics.
915, A65.
mla: Liu, T., et al. “Decay of Streaks and Rolls in Plane Couette-Poiseuille Flow.”
Journal of Fluid Mechanics, vol. 915, A65, Cambridge University Press,
2021, doi:10.1017/jfm.2021.89.
short: T. Liu, B. Semin, L. Klotz, R. Godoy-Diana, J.E. Wesfreid, T. Mullin, Journal
of Fluid Mechanics 915 (2021).
date_created: 2021-03-28T22:01:42Z
date_published: 2021-03-17T00:00:00Z
date_updated: 2023-08-07T14:30:11Z
day: '17'
department:
- _id: BjHo
doi: 10.1017/jfm.2021.89
external_id:
arxiv:
- '2008.08851'
isi:
- '000629677500001'
intvolume: ' 915'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2008.08851
month: '03'
oa: 1
oa_version: Preprint
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Decay of streaks and rolls in plane Couette-Poiseuille flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 915
year: '2021'
...
---
_id: '9407'
abstract:
- lang: eng
text: 'High impact epidemics constitute one of the largest threats humanity is facing
in the 21st century. In the absence of pharmaceutical interventions, physical
distancing together with testing, contact tracing and quarantining are crucial
in slowing down epidemic dynamics. Yet, here we show that if testing capacities
are limited, containment may fail dramatically because such combined countermeasures
drastically change the rules of the epidemic transition: Instead of continuous,
the response to countermeasures becomes discontinuous. Rather than following the
conventional exponential growth, the outbreak that is initially strongly suppressed
eventually accelerates and scales faster than exponential during an explosive
growth period. As a consequence, containment measures either suffice to stop the
outbreak at low total case numbers or fail catastrophically if marginally too
weak, thus implying large uncertainties in reliably estimating overall epidemic
dynamics, both during initial phases and during second wave scenarios.'
acknowledgement: The authors thank Malte Schröder for valuable discussions and creating
the scale-free network topologies. B.H. thanks Mukund Vasudevan for helpful discussion.
The research by M.T. was supported by the Deutsche Forschungsgemeinschaft (DFG,
German Research Foundation) under Germany´s Excellence Strategy–EXC-2068–390729961–Cluster
of Excellence Physics of Life of TU Dresden.
article_number: '2586'
article_processing_charge: No
article_type: original
author:
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Marc
full_name: Timme, Marc
last_name: Timme
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Scarselli D, Budanur NB, Timme M, Hof B. Discontinuous epidemic transition
due to limited testing. Nature Communications. 2021;12(1). doi:10.1038/s41467-021-22725-9
apa: Scarselli, D., Budanur, N. B., Timme, M., & Hof, B. (2021). Discontinuous
epidemic transition due to limited testing. Nature Communications. Springer
Nature. https://doi.org/10.1038/s41467-021-22725-9
chicago: Scarselli, Davide, Nazmi B Budanur, Marc Timme, and Björn Hof. “Discontinuous
Epidemic Transition Due to Limited Testing.” Nature Communications. Springer
Nature, 2021. https://doi.org/10.1038/s41467-021-22725-9.
ieee: D. Scarselli, N. B. Budanur, M. Timme, and B. Hof, “Discontinuous epidemic
transition due to limited testing,” Nature Communications, vol. 12, no.
1. Springer Nature, 2021.
ista: Scarselli D, Budanur NB, Timme M, Hof B. 2021. Discontinuous epidemic transition
due to limited testing. Nature Communications. 12(1), 2586.
mla: Scarselli, Davide, et al. “Discontinuous Epidemic Transition Due to Limited
Testing.” Nature Communications, vol. 12, no. 1, 2586, Springer Nature,
2021, doi:10.1038/s41467-021-22725-9.
short: D. Scarselli, N.B. Budanur, M. Timme, B. Hof, Nature Communications 12 (2021).
date_created: 2021-05-23T22:01:42Z
date_published: 2021-05-10T00:00:00Z
date_updated: 2023-08-08T13:45:13Z
day: '10'
ddc:
- '570'
department:
- _id: BjHo
doi: 10.1038/s41467-021-22725-9
external_id:
isi:
- '000687305500044'
file:
- access_level: open_access
checksum: fe26c1b8a7da1ae07a6c03f80ff06ea1
content_type: application/pdf
creator: kschuh
date_created: 2021-05-25T14:18:40Z
date_updated: 2021-05-25T14:18:40Z
file_id: '9426'
file_name: 2021_NatureCommunications_Scarselli.pdf
file_size: 1176573
relation: main_file
success: 1
file_date_updated: 2021-05-25T14:18:40Z
has_accepted_license: '1'
intvolume: ' 12'
isi: 1
issue: '1'
language:
- iso: eng
month: '05'
oa: 1
oa_version: Published Version
publication: Nature Communications
publication_identifier:
eissn:
- '20411723'
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
link:
- description: News on IST Homepage
relation: press_release
url: https://ist.ac.at/en/news/smashing-the-covid-curve/
scopus_import: '1'
status: public
title: Discontinuous epidemic transition due to limited testing
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 12
year: '2021'
...
---
_id: '9467'
abstract:
- lang: eng
text: "Turbulence in the flow of fluid through a pipe can be suppressed by buoyancy
forces. As the suppression of turbulence leads to severe heat transfer deterioration,
this is an important and undesirable phenomenon in both heating and cooling applications.
Vertical flow is often considered, as the axial buoyancy force can help drive
the flow. With heating measured by the buoyancy parameter \U0001D436, our direct
numerical simulations show that shear-driven turbulence may either be completely
laminarised or it transitions to a relatively quiescent convection-driven state.
Buoyancy forces cause a flattening of the base flow profile, which in isothermal
pipe flow has recently been linked to complete suppression of turbulence (Kühnen
et al., Nat. Phys., vol. 14, 2018, pp. 386–390), and the flattened laminar base
profile has enhanced nonlinear stability (Marensi et al., J. Fluid Mech., vol.
863, 2019, pp. 50–875). In agreement with these findings, the nonlinear lower-branch
travelling-wave solution analysed here, which is believed to mediate transition
to turbulence in isothermal pipe flow, is shown to be suppressed by buoyancy.
A linear instability of the laminar base flow is responsible for the appearance
of the relatively quiescent convection driven state for \U0001D436≳4 across the
range of Reynolds numbers considered. In the suppression of turbulence, however,
i.e. in the transition from turbulence, we find clearer association with the analysis
of He et al. (J. Fluid Mech., vol. 809, 2016, pp. 31–71) than with the above dynamical
systems approach, which describes better the transition to turbulence. The laminarisation
criterion He et al. propose, based on an apparent Reynolds number of the flow
as measured by its driving pressure gradient, is found to capture the critical
\U0001D436=\U0001D436\U0001D450\U0001D45F(\U0001D445\U0001D452) above which the
flow will be laminarised or switch to the convection-driven type. Our analysis
suggests that it is the weakened rolls, rather than the streaks, which appear
to be critical for laminarisation."
acknowledgement: The anonymous referees are kindly acknowledged for their useful suggestions
andcomments.
article_number: A17
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Elena
full_name: Marensi, Elena
id: 0BE7553A-1004-11EA-B805-18983DDC885E
last_name: Marensi
- first_name: Shuisheng
full_name: He, Shuisheng
last_name: He
- first_name: Ashley P.
full_name: Willis, Ashley P.
last_name: Willis
citation:
ama: Marensi E, He S, Willis AP. Suppression of turbulence and travelling waves
in a vertical heated pipe. Journal of Fluid Mechanics. 2021;919. doi:10.1017/jfm.2021.371
apa: Marensi, E., He, S., & Willis, A. P. (2021). Suppression of turbulence
and travelling waves in a vertical heated pipe. Journal of Fluid Mechanics.
Cambridge University Press. https://doi.org/10.1017/jfm.2021.371
chicago: Marensi, Elena, Shuisheng He, and Ashley P. Willis. “Suppression of Turbulence
and Travelling Waves in a Vertical Heated Pipe.” Journal of Fluid Mechanics.
Cambridge University Press, 2021. https://doi.org/10.1017/jfm.2021.371.
ieee: E. Marensi, S. He, and A. P. Willis, “Suppression of turbulence and travelling
waves in a vertical heated pipe,” Journal of Fluid Mechanics, vol. 919.
Cambridge University Press, 2021.
ista: Marensi E, He S, Willis AP. 2021. Suppression of turbulence and travelling
waves in a vertical heated pipe. Journal of Fluid Mechanics. 919, A17.
mla: Marensi, Elena, et al. “Suppression of Turbulence and Travelling Waves in a
Vertical Heated Pipe.” Journal of Fluid Mechanics, vol. 919, A17, Cambridge
University Press, 2021, doi:10.1017/jfm.2021.371.
short: E. Marensi, S. He, A.P. Willis, Journal of Fluid Mechanics 919 (2021).
date_created: 2021-06-06T22:01:30Z
date_published: 2021-07-25T00:00:00Z
date_updated: 2023-08-08T13:58:41Z
day: '25'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2021.371
external_id:
arxiv:
- '2008.13486'
isi:
- '000653785000001'
file:
- access_level: open_access
checksum: 867ad077e45c181c2c5ec1311ba27c41
content_type: application/pdf
creator: kschuh
date_created: 2021-08-03T09:53:28Z
date_updated: 2021-08-03T09:53:28Z
file_id: '9766'
file_name: 2021_JournalFluidMechanics_Marensi.pdf
file_size: 4087358
relation: main_file
success: 1
file_date_updated: 2021-08-03T09:53:28Z
has_accepted_license: '1'
intvolume: ' 919'
isi: 1
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- '14697645'
issn:
- '00221120'
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Suppression of turbulence and travelling waves in a vertical heated pipe
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 919
year: '2021'
...
---
_id: '9558'
abstract:
- lang: eng
text: "We show that turbulent dynamics that arise in simulations of the three-dimensional
Navier--Stokes equations in a triply-periodic domain under sinusoidal forcing
can be described as transient visits to the neighborhoods of unstable time-periodic
solutions. Based on this description, we reduce the original system with more
than 10^5 degrees of freedom to a 17-node Markov chain where each node corresponds
to the neighborhood of a periodic orbit. The model accurately reproduces long-term
averages of the system's observables as weighted sums over the periodic orbits.\r\n"
acknowledged_ssus:
- _id: ScienComp
acknowledgement: "We thank the referees for improving this Letter with their comments.
We acknowledge stimulating discussions with\r\nH. Edelsbrunner. This work was supported
by Grant No. 662960 from the Simons Foundation (B. H.). The numerical calculations
were performed at TUBITAK ULAKBIM High Performance and Grid Computing Center (TRUBA
resources) and IST Austria High Performance Computing cluster."
article_number: '244502'
article_processing_charge: No
article_type: letter_note
author:
- first_name: Gökhan
full_name: Yalniz, Gökhan
id: 66E74FA2-D8BF-11E9-8249-8DE2E5697425
last_name: Yalniz
orcid: 0000-0002-8490-9312
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
citation:
ama: Yalniz G, Hof B, Budanur NB. Coarse graining the state space of a turbulent
flow using periodic orbits. Physical Review Letters. 2021;126(24). doi:10.1103/PhysRevLett.126.244502
apa: Yalniz, G., Hof, B., & Budanur, N. B. (2021). Coarse graining the state
space of a turbulent flow using periodic orbits. Physical Review Letters.
American Physical Society. https://doi.org/10.1103/PhysRevLett.126.244502
chicago: Yalniz, Gökhan, Björn Hof, and Nazmi B Budanur. “Coarse Graining the State
Space of a Turbulent Flow Using Periodic Orbits.” Physical Review Letters.
American Physical Society, 2021. https://doi.org/10.1103/PhysRevLett.126.244502.
ieee: G. Yalniz, B. Hof, and N. B. Budanur, “Coarse graining the state space of
a turbulent flow using periodic orbits,” Physical Review Letters, vol.
126, no. 24. American Physical Society, 2021.
ista: Yalniz G, Hof B, Budanur NB. 2021. Coarse graining the state space of a turbulent
flow using periodic orbits. Physical Review Letters. 126(24), 244502.
mla: Yalniz, Gökhan, et al. “Coarse Graining the State Space of a Turbulent Flow
Using Periodic Orbits.” Physical Review Letters, vol. 126, no. 24, 244502,
American Physical Society, 2021, doi:10.1103/PhysRevLett.126.244502.
short: G. Yalniz, B. Hof, N.B. Budanur, Physical Review Letters 126 (2021).
date_created: 2021-06-16T15:45:36Z
date_published: 2021-06-18T00:00:00Z
date_updated: 2023-08-08T14:08:36Z
day: '18'
department:
- _id: GradSch
- _id: BjHo
doi: 10.1103/PhysRevLett.126.244502
external_id:
arxiv:
- '2007.02584'
isi:
- '000663310100008'
intvolume: ' 126'
isi: 1
issue: '24'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2007.02584
month: '06'
oa: 1
oa_version: Preprint
project:
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
grant_number: '662960'
name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
Studies on Transitional and Turbulent Flows'
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
related_material:
link:
- description: News on IST Homepage
relation: press_release
url: https://ist.ac.at/en/news/turbulent-flow-simplified/
status: public
title: Coarse graining the state space of a turbulent flow using periodic orbits
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 126
year: '2021'
...
---
_id: '10203'
abstract:
- lang: eng
text: Single photon emitters in atomically-thin semiconductors can be deterministically
positioned using strain induced by underlying nano-structures. Here, we couple
monolayer WSe2 to high-refractive-index gallium phosphide dielectric nano-antennas
providing both optical enhancement and monolayer deformation. For single photon
emitters formed on such nano-antennas, we find very low (femto-Joule) saturation
pulse energies and up to 104 times brighter photoluminescence than in WSe2 placed
on low-refractive-index SiO2 pillars. We show that the key to these observations
is the increase on average by a factor of 5 of the quantum efficiency of the emitters
coupled to the nano-antennas. This further allows us to gain new insights into
their photoluminescence dynamics, revealing the roles of the dark exciton reservoir
and Auger processes. We also find that the coherence time of such emitters is
limited by intrinsic dephasing processes. Our work establishes dielectric nano-antennas
as a platform for high-efficiency quantum light generation in monolayer semiconductors.
acknowledgement: L.S., P.G.Z., and A.I.T. thank the financial support of the European
Graphene Flagship Project under grant agreements 881603 and EPSRC grant EP/S030751/1.
L.S. and A.I.T. thank the European Union’s Horizon 2020 research and innovation
programme under ITN Spin-NANO Marie Sklodowska-Curie grant agreement no. 676108.
P.G.Z. and A.I.T. thank the European Union’s Horizon 2020 research and innovation
programme under ITN 4PHOTON Marie Sklodowska-Curie grant agreement no. 721394. J.C.,
S.A.M., and R.S. acknowledge funding by EPSRC (EP/P033369 and EP/M013812). C.L.P.,
A.J.B., A.I.T., and A.M.F. acknowledge funding by EPSRC Programme Grant EP/N031776/1.
S.A.M. acknowledges the Lee-Lucas Chair in Physics, the Solar Energies go Hybrid
(SolTech) programme, and the Deutsche Forschungsgemeinschaft (DFG, German Research
Foundation) under Germany’s Excellence Strategy - EXC 2089/1 - 390776260.
article_number: '6063'
article_processing_charge: No
article_type: original
author:
- first_name: Luca
full_name: Sortino, Luca
last_name: Sortino
- first_name: Panaiot G.
full_name: Zotev, Panaiot G.
last_name: Zotev
- first_name: Catherine L.
full_name: Phillips, Catherine L.
last_name: Phillips
- first_name: Alistair J.
full_name: Brash, Alistair J.
last_name: Brash
- first_name: Javier
full_name: Cambiasso, Javier
last_name: Cambiasso
- first_name: Elena
full_name: Marensi, Elena
id: 0BE7553A-1004-11EA-B805-18983DDC885E
last_name: Marensi
orcid: 0000-0001-7173-4923
- first_name: A. Mark
full_name: Fox, A. Mark
last_name: Fox
- first_name: Stefan A.
full_name: Maier, Stefan A.
last_name: Maier
- first_name: Riccardo
full_name: Sapienza, Riccardo
last_name: Sapienza
- first_name: Alexander I.
full_name: Tartakovskii, Alexander I.
last_name: Tartakovskii
citation:
ama: Sortino L, Zotev PG, Phillips CL, et al. Bright single photon emitters with
enhanced quantum efficiency in a two-dimensional semiconductor coupled with dielectric
nano-antennas. Nature Communications. 2021;12. doi:10.1038/s41467-021-26262-3
apa: Sortino, L., Zotev, P. G., Phillips, C. L., Brash, A. J., Cambiasso, J., Marensi,
E., … Tartakovskii, A. I. (2021). Bright single photon emitters with enhanced
quantum efficiency in a two-dimensional semiconductor coupled with dielectric
nano-antennas. Nature Communications. Springer Nature. https://doi.org/10.1038/s41467-021-26262-3
chicago: Sortino, Luca, Panaiot G. Zotev, Catherine L. Phillips, Alistair J. Brash,
Javier Cambiasso, Elena Marensi, A. Mark Fox, Stefan A. Maier, Riccardo Sapienza,
and Alexander I. Tartakovskii. “Bright Single Photon Emitters with Enhanced Quantum
Efficiency in a Two-Dimensional Semiconductor Coupled with Dielectric Nano-Antennas.”
Nature Communications. Springer Nature, 2021. https://doi.org/10.1038/s41467-021-26262-3.
ieee: L. Sortino et al., “Bright single photon emitters with enhanced quantum
efficiency in a two-dimensional semiconductor coupled with dielectric nano-antennas,”
Nature Communications, vol. 12. Springer Nature, 2021.
ista: Sortino L, Zotev PG, Phillips CL, Brash AJ, Cambiasso J, Marensi E, Fox AM,
Maier SA, Sapienza R, Tartakovskii AI. 2021. Bright single photon emitters with
enhanced quantum efficiency in a two-dimensional semiconductor coupled with dielectric
nano-antennas. Nature Communications. 12, 6063.
mla: Sortino, Luca, et al. “Bright Single Photon Emitters with Enhanced Quantum
Efficiency in a Two-Dimensional Semiconductor Coupled with Dielectric Nano-Antennas.”
Nature Communications, vol. 12, 6063, Springer Nature, 2021, doi:10.1038/s41467-021-26262-3.
short: L. Sortino, P.G. Zotev, C.L. Phillips, A.J. Brash, J. Cambiasso, E. Marensi,
A.M. Fox, S.A. Maier, R. Sapienza, A.I. Tartakovskii, Nature Communications 12
(2021).
date_created: 2021-10-31T23:01:30Z
date_published: 2021-10-18T00:00:00Z
date_updated: 2023-08-14T08:12:12Z
day: '18'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1038/s41467-021-26262-3
external_id:
arxiv:
- '2103.16986'
isi:
- '000708601800015'
file:
- access_level: open_access
checksum: 8580d128389860f732028c521cd5949e
content_type: application/pdf
creator: cchlebak
date_created: 2021-11-03T11:31:24Z
date_updated: 2021-11-03T11:31:24Z
file_id: '10212'
file_name: 2021_NatComm_Sortino.pdf
file_size: 1434201
relation: main_file
success: 1
file_date_updated: 2021-11-03T11:31:24Z
has_accepted_license: '1'
intvolume: ' 12'
isi: 1
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
publication: Nature Communications
publication_identifier:
eissn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Bright single photon emitters with enhanced quantum efficiency in a two-dimensional
semiconductor coupled with dielectric nano-antennas
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 12
year: '2021'
...
---
_id: '10299'
abstract:
- lang: eng
text: Turbulence generally arises in shear flows if velocities and hence, inertial
forces are sufficiently large. In striking contrast, viscoelastic fluids can exhibit
disordered motion even at vanishing inertia. Intermediate between these cases,
a state of chaotic motion, “elastoinertial turbulence” (EIT), has been observed
in a narrow Reynolds number interval. We here determine the origin of EIT in experiments
and show that characteristic EIT structures can be detected across an unexpectedly
wide range of parameters. Close to onset, a pattern of chevron-shaped streaks
emerges in qualitative agreement with linear and weakly nonlinear theory. However,
in experiments, the dynamics remain weakly chaotic, and the instability can be
traced to far lower Reynolds numbers than permitted by theory. For increasing
inertia, the flow undergoes a transformation to a wall mode composed of inclined
near-wall streaks and shear layers. This mode persists to what is known as the
“maximum drag reduction limit,” and overall EIT is found to dominate viscoelastic
flows across more than three orders of magnitude in Reynolds number.
acknowledgement: We thank Y. Dubief, R. Kerswell, E. Marensi, V. Shankar, V. Steinberg,
and V. Terrapon for discussions and helpful comments. A.V. and B.H. acknowledge
funding from the Austrian Science Fund, grant I4188-N30, within the Deutsche Forschungsgemeinschaft
research unit FOR 2688.
article_number: e2102350118
article_processing_charge: No
article_type: original
author:
- first_name: George H
full_name: Choueiri, George H
id: 448BD5BC-F248-11E8-B48F-1D18A9856A87
last_name: Choueiri
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
- first_name: Sarath
full_name: Sankar, Sarath
last_name: Sankar
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Choueiri GH, Lopez Alonso JM, Varshney A, Sankar S, Hof B. Experimental observation
of the origin and structure of elastoinertial turbulence. Proceedings of the
National Academy of Sciences. 2021;118(45). doi:10.1073/pnas.2102350118
apa: Choueiri, G. H., Lopez Alonso, J. M., Varshney, A., Sankar, S., & Hof,
B. (2021). Experimental observation of the origin and structure of elastoinertial
turbulence. Proceedings of the National Academy of Sciences. National Academy
of Sciences. https://doi.org/10.1073/pnas.2102350118
chicago: Choueiri, George H, Jose M Lopez Alonso, Atul Varshney, Sarath Sankar,
and Björn Hof. “Experimental Observation of the Origin and Structure of Elastoinertial
Turbulence.” Proceedings of the National Academy of Sciences. National
Academy of Sciences, 2021. https://doi.org/10.1073/pnas.2102350118.
ieee: G. H. Choueiri, J. M. Lopez Alonso, A. Varshney, S. Sankar, and B. Hof, “Experimental
observation of the origin and structure of elastoinertial turbulence,” Proceedings
of the National Academy of Sciences, vol. 118, no. 45. National Academy of
Sciences, 2021.
ista: Choueiri GH, Lopez Alonso JM, Varshney A, Sankar S, Hof B. 2021. Experimental
observation of the origin and structure of elastoinertial turbulence. Proceedings
of the National Academy of Sciences. 118(45), e2102350118.
mla: Choueiri, George H., et al. “Experimental Observation of the Origin and Structure
of Elastoinertial Turbulence.” Proceedings of the National Academy of Sciences,
vol. 118, no. 45, e2102350118, National Academy of Sciences, 2021, doi:10.1073/pnas.2102350118.
short: G.H. Choueiri, J.M. Lopez Alonso, A. Varshney, S. Sankar, B. Hof, Proceedings
of the National Academy of Sciences 118 (2021).
date_created: 2021-11-17T13:24:24Z
date_published: 2021-11-03T00:00:00Z
date_updated: 2023-08-14T11:50:10Z
day: '03'
department:
- _id: BjHo
doi: 10.1073/pnas.2102350118
external_id:
arxiv:
- '2103.00023'
isi:
- '000720926900019'
pmid:
- ' 34732570'
intvolume: ' 118'
isi: 1
issue: '45'
keyword:
- multidisciplinary
- elastoinertial turbulence
- viscoelastic flows
- elastic instability
- drag reduction
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2103.00023
month: '11'
oa: 1
oa_version: Preprint
pmid: 1
project:
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
call_identifier: FWF
grant_number: I04188
name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
publication: Proceedings of the National Academy of Sciences
publication_identifier:
eissn:
- 1091-6490
issn:
- 0027-8424
publication_status: published
publisher: National Academy of Sciences
quality_controlled: '1'
scopus_import: '1'
status: public
title: Experimental observation of the origin and structure of elastoinertial turbulence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 118
year: '2021'
...
---
_id: '9728'
abstract:
- lang: eng
text: "Most real-world flows are multiphase, yet we know little about them compared
to their single-phase counterparts. Multiphase flows are more difficult to investigate
as their dynamics occur in large parameter space and involve complex phenomena
such as preferential concentration, turbulence modulation, non-Newtonian rheology,
etc. Over the last few decades, experiments in particle-laden flows have taken
a back seat in favour of ever-improving computational resources. However, computers
are still not powerful enough to simulate a real-world fluid with millions of
finite-size particles. Experiments are essential not only because they offer a
reliable way to investigate real-world multiphase flows but also because they
serve to validate numerical studies and steer the research in a relevant direction.
In this work, we have experimentally investigated particle-laden flows in pipes,
and in particular, examined the effect of particles on the laminar-turbulent transition
and the drag scaling in turbulent flows.\r\n\r\nFor particle-laden pipe flows,
an earlier study [Matas et al., 2003] reported how the sub-critical (i.e., hysteretic)
transition that occurs via localised turbulent structures called puffs is affected
by the addition of particles. In this study, in addition to this known transition,
we found a super-critical transition to a globally fluctuating state with increasing
particle concentration. At the same time, the Newtonian-type transition via puffs
is delayed to larger Reynolds numbers. At an even higher concentration, only the
globally fluctuating state is found. The dynamics of particle-laden flows are
hence determined by two competing instabilities that give rise to three flow regimes:
Newtonian-type turbulence at low, a particle-induced globally fluctuating state
at high, and a coexistence state at intermediate concentrations.\r\n\r\nThe effect
of particles on turbulent drag is ambiguous, with studies reporting drag reduction,
no net change, and even drag increase. The ambiguity arises because, in addition
to particle concentration, particle shape, size, and density also affect the net
drag. Even similar particles might affect the flow dissimilarly in different Reynolds
number and concentration ranges. In the present study, we explored a wide range
of both Reynolds number and concentration, using spherical as well as cylindrical
particles. We found that the spherical particles do not reduce drag while the
cylindrical particles are drag-reducing within a specific Reynolds number interval.
The interval strongly depends on the particle concentration and the relative size
of the pipe and particles. Within this interval, the magnitude of drag reduction
reaches a maximum. These drag reduction maxima appear to fall onto a distinct
power-law curve irrespective of the pipe diameter and particle concentration,
and this curve can be considered as the maximum drag reduction asymptote for a
given fibre shape. Such an asymptote is well known for polymeric flows but had
not been identified for particle-laden flows prior to this work."
acknowledged_ssus:
- _id: M-Shop
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Nishchal
full_name: Agrawal, Nishchal
id: 469E6004-F248-11E8-B48F-1D18A9856A87
last_name: Agrawal
citation:
ama: Agrawal N. Transition to turbulence and drag reduction in particle-laden pipe
flows. 2021. doi:10.15479/at:ista:9728
apa: Agrawal, N. (2021). Transition to turbulence and drag reduction in particle-laden
pipe flows. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:9728
chicago: Agrawal, Nishchal. “Transition to Turbulence and Drag Reduction in Particle-Laden
Pipe Flows.” Institute of Science and Technology Austria, 2021. https://doi.org/10.15479/at:ista:9728.
ieee: N. Agrawal, “Transition to turbulence and drag reduction in particle-laden
pipe flows,” Institute of Science and Technology Austria, 2021.
ista: Agrawal N. 2021. Transition to turbulence and drag reduction in particle-laden
pipe flows. Institute of Science and Technology Austria.
mla: Agrawal, Nishchal. Transition to Turbulence and Drag Reduction in Particle-Laden
Pipe Flows. Institute of Science and Technology Austria, 2021, doi:10.15479/at:ista:9728.
short: N. Agrawal, Transition to Turbulence and Drag Reduction in Particle-Laden
Pipe Flows, Institute of Science and Technology Austria, 2021.
date_created: 2021-07-27T13:40:30Z
date_published: 2021-07-29T00:00:00Z
date_updated: 2024-02-28T13:14:39Z
day: '29'
ddc:
- '532'
degree_awarded: PhD
department:
- _id: GradSch
- _id: BjHo
doi: 10.15479/at:ista:9728
file:
- access_level: closed
checksum: 77436be3563a90435024307b1b5ee7e8
content_type: application/x-zip-compressed
creator: nagrawal
date_created: 2021-07-28T13:32:02Z
date_updated: 2022-07-29T22:30:05Z
embargo_to: open_access
file_id: '9744'
file_name: Transition to Turbulence and Drag Reduction in Particle-Laden Pipe Flows.zip
file_size: 22859658
relation: source_file
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checksum: 72a891d7daba85445c29b868c22575ed
content_type: application/pdf
creator: nagrawal
date_created: 2021-07-28T13:32:05Z
date_updated: 2022-07-29T22:30:05Z
embargo: 2022-07-28
file_id: '9745'
file_name: Transition to Turbulence and Drag Reduction in Particle-Laden Pipe Flows.pdf
file_size: 18658048
relation: main_file
file_date_updated: 2022-07-29T22:30:05Z
has_accepted_license: '1'
keyword:
- Drag Reduction
- Transition to Turbulence
- Multiphase Flows
- particle Laden Flows
- Complex Flows
- Experiments
- Fluid Dynamics
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
page: '118'
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '6189'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: Transition to turbulence and drag reduction in particle-laden pipe flows
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2021'
...
---
_id: '7364'
abstract:
- lang: eng
text: We present nsCouette, a highly scalable software tool to solve the Navier–Stokes
equations for incompressible fluid flow between differentially heated and independently
rotating, concentric cylinders. It is based on a pseudospectral spatial discretization
and dynamic time-stepping. It is implemented in modern Fortran with a hybrid MPI-OpenMP
parallelization scheme and thus designed to compute turbulent flows at high Reynolds
and Rayleigh numbers. An additional GPU implementation (C-CUDA) for intermediate
problem sizes and a version for pipe flow (nsPipe) are also provided.
article_number: '100395'
article_processing_charge: No
article_type: original
author:
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: Daniel
full_name: Feldmann, Daniel
last_name: Feldmann
- first_name: Markus
full_name: Rampp, Markus
last_name: Rampp
- first_name: Alberto
full_name: Vela-Martín, Alberto
last_name: Vela-Martín
- first_name: Liang
full_name: Shi, Liang
id: 374A3F1A-F248-11E8-B48F-1D18A9856A87
last_name: Shi
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
citation:
ama: Lopez Alonso JM, Feldmann D, Rampp M, Vela-Martín A, Shi L, Avila M. nsCouette
– A high-performance code for direct numerical simulations of turbulent Taylor–Couette
flow. SoftwareX. 2020;11. doi:10.1016/j.softx.2019.100395
apa: Lopez Alonso, J. M., Feldmann, D., Rampp, M., Vela-Martín, A., Shi, L., &
Avila, M. (2020). nsCouette – A high-performance code for direct numerical simulations
of turbulent Taylor–Couette flow. SoftwareX. Elsevier. https://doi.org/10.1016/j.softx.2019.100395
chicago: Lopez Alonso, Jose M, Daniel Feldmann, Markus Rampp, Alberto Vela-Martín,
Liang Shi, and Marc Avila. “NsCouette – A High-Performance Code for Direct Numerical
Simulations of Turbulent Taylor–Couette Flow.” SoftwareX. Elsevier, 2020.
https://doi.org/10.1016/j.softx.2019.100395.
ieee: J. M. Lopez Alonso, D. Feldmann, M. Rampp, A. Vela-Martín, L. Shi, and M.
Avila, “nsCouette – A high-performance code for direct numerical simulations of
turbulent Taylor–Couette flow,” SoftwareX, vol. 11. Elsevier, 2020.
ista: Lopez Alonso JM, Feldmann D, Rampp M, Vela-Martín A, Shi L, Avila M. 2020.
nsCouette – A high-performance code for direct numerical simulations of turbulent
Taylor–Couette flow. SoftwareX. 11, 100395.
mla: Lopez Alonso, Jose M., et al. “NsCouette – A High-Performance Code for Direct
Numerical Simulations of Turbulent Taylor–Couette Flow.” SoftwareX, vol.
11, 100395, Elsevier, 2020, doi:10.1016/j.softx.2019.100395.
short: J.M. Lopez Alonso, D. Feldmann, M. Rampp, A. Vela-Martín, L. Shi, M. Avila,
SoftwareX 11 (2020).
date_created: 2020-01-26T23:00:35Z
date_published: 2020-01-17T00:00:00Z
date_updated: 2023-08-17T14:29:59Z
day: '17'
ddc:
- '000'
department:
- _id: BjHo
doi: 10.1016/j.softx.2019.100395
external_id:
arxiv:
- '1908.00587'
isi:
- '000552271200011'
file:
- access_level: open_access
checksum: 2af1a1a3cc33557b345145276f221668
content_type: application/pdf
creator: dernst
date_created: 2020-01-27T07:32:46Z
date_updated: 2020-07-14T12:47:56Z
file_id: '7365'
file_name: 2020_SoftwareX_Lopez.pdf
file_size: 679707
relation: main_file
file_date_updated: 2020-07-14T12:47:56Z
has_accepted_license: '1'
intvolume: ' 11'
isi: 1
language:
- iso: eng
month: '01'
oa: 1
oa_version: Published Version
publication: SoftwareX
publication_identifier:
eissn:
- '23527110'
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: nsCouette – A high-performance code for direct numerical simulations of turbulent
Taylor–Couette flow
tmp:
image: /images/cc_by_nc_nd.png
legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
(CC BY-NC-ND 4.0)
short: CC BY-NC-ND (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 11
year: '2020'
...
---
_id: '7534'
abstract:
- lang: eng
text: 'In the past two decades, our understanding of the transition to turbulence
in shear flows with linearly stable laminar solutions has greatly improved. Regarding
the susceptibility of the laminar flow, two concepts have been particularly useful:
the edge states and the minimal seeds. In this nonlinear picture of the transition,
the basin boundary of turbulence is set by the edge state''s stable manifold and
this manifold comes closest in energy to the laminar equilibrium at the minimal
seed. We begin this paper by presenting numerical experiments in which three-dimensional
perturbations are too energetic to trigger turbulence in pipe flow but they do
lead to turbulence when their amplitude is reduced. We show that this seemingly
counterintuitive observation is in fact consistent with the fully nonlinear description
of the transition mediated by the edge state. In order to understand the physical
mechanisms behind this process, we measure the turbulent kinetic energy production
and dissipation rates as a function of the radial coordinate. Our main observation
is that the transition to turbulence relies on the energy amplification away from
the wall, as opposed to the turbulence itself, whose energy is predominantly produced
near the wall. This observation is further supported by the similar analyses on
the minimal seeds and the edge states. Furthermore, we show that the time evolution
of production-over-dissipation curves provides a clear distinction between the
different initial amplification stages of the transition to turbulence from the
minimal seed.'
article_number: '023903'
article_processing_charge: No
article_type: original
author:
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Elena
full_name: Marensi, Elena
last_name: Marensi
- first_name: Ashley P.
full_name: Willis, Ashley P.
last_name: Willis
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Budanur NB, Marensi E, Willis AP, Hof B. Upper edge of chaos and the energetics
of transition in pipe flow. Physical Review Fluids. 2020;5(2). doi:10.1103/physrevfluids.5.023903
apa: Budanur, N. B., Marensi, E., Willis, A. P., & Hof, B. (2020). Upper edge
of chaos and the energetics of transition in pipe flow. Physical Review Fluids.
American Physical Society. https://doi.org/10.1103/physrevfluids.5.023903
chicago: Budanur, Nazmi B, Elena Marensi, Ashley P. Willis, and Björn Hof. “Upper
Edge of Chaos and the Energetics of Transition in Pipe Flow.” Physical Review
Fluids. American Physical Society, 2020. https://doi.org/10.1103/physrevfluids.5.023903.
ieee: N. B. Budanur, E. Marensi, A. P. Willis, and B. Hof, “Upper edge of chaos
and the energetics of transition in pipe flow,” Physical Review Fluids,
vol. 5, no. 2. American Physical Society, 2020.
ista: Budanur NB, Marensi E, Willis AP, Hof B. 2020. Upper edge of chaos and the
energetics of transition in pipe flow. Physical Review Fluids. 5(2), 023903.
mla: Budanur, Nazmi B., et al. “Upper Edge of Chaos and the Energetics of Transition
in Pipe Flow.” Physical Review Fluids, vol. 5, no. 2, 023903, American
Physical Society, 2020, doi:10.1103/physrevfluids.5.023903.
short: N.B. Budanur, E. Marensi, A.P. Willis, B. Hof, Physical Review Fluids 5 (2020).
date_created: 2020-02-27T10:26:57Z
date_published: 2020-02-21T00:00:00Z
date_updated: 2023-08-18T06:44:46Z
day: '21'
department:
- _id: BjHo
doi: 10.1103/physrevfluids.5.023903
external_id:
arxiv:
- '1912.09270'
isi:
- '000515065100001'
intvolume: ' 5'
isi: 1
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1912.09270
month: '02'
oa: 1
oa_version: Preprint
publication: Physical Review Fluids
publication_identifier:
issn:
- 2469-990X
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Upper edge of chaos and the energetics of transition in pipe flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 5
year: '2020'
...
---
_id: '7563'
abstract:
- lang: eng
text: "We introduce “state space persistence analysis” for deducing the symbolic
dynamics of time series data obtained from high-dimensional chaotic attractors.
To this end, we adapt a topological data analysis technique known as persistent
homology for the characterization of state space projections of chaotic trajectories
and periodic orbits. By comparing the shapes along a chaotic trajectory to those
of the periodic orbits, state space persistence analysis quantifies the shape
similarity of chaotic trajectory segments and periodic orbits. We demonstrate
the method by applying it to the three-dimensional Rössler system and a 30-dimensional
discretization of the Kuramoto–Sivashinsky partial differential equation in (1+1)
dimensions.\r\nOne way of studying chaotic attractors systematically is through
their symbolic dynamics, in which one partitions the state space into qualitatively
different regions and assigns a symbol to each such region.1–3 This yields a “coarse-grained”
state space of the system, which can then be reduced to a Markov chain encoding
all possible transitions between the states of the system. While it is possible
to obtain the symbolic dynamics of low-dimensional chaotic systems with standard
tools such as Poincaré maps, when applied to high-dimensional systems such as
turbulent flows, these tools alone are not sufficient to determine symbolic dynamics.4,5
In this paper, we develop “state space persistence analysis” and demonstrate that
it can be utilized to infer the symbolic dynamics in very high-dimensional settings."
article_number: '033109'
article_processing_charge: No
article_type: original
author:
- first_name: Gökhan
full_name: Yalniz, Gökhan
id: 66E74FA2-D8BF-11E9-8249-8DE2E5697425
last_name: Yalniz
orcid: 0000-0002-8490-9312
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
citation:
ama: Yalniz G, Budanur NB. Inferring symbolic dynamics of chaotic flows from persistence.
Chaos. 2020;30(3). doi:10.1063/1.5122969
apa: Yalniz, G., & Budanur, N. B. (2020). Inferring symbolic dynamics of chaotic
flows from persistence. Chaos. AIP Publishing. https://doi.org/10.1063/1.5122969
chicago: Yalniz, Gökhan, and Nazmi B Budanur. “Inferring Symbolic Dynamics of Chaotic
Flows from Persistence.” Chaos. AIP Publishing, 2020. https://doi.org/10.1063/1.5122969.
ieee: G. Yalniz and N. B. Budanur, “Inferring symbolic dynamics of chaotic flows
from persistence,” Chaos, vol. 30, no. 3. AIP Publishing, 2020.
ista: Yalniz G, Budanur NB. 2020. Inferring symbolic dynamics of chaotic flows from
persistence. Chaos. 30(3), 033109.
mla: Yalniz, Gökhan, and Nazmi B. Budanur. “Inferring Symbolic Dynamics of Chaotic
Flows from Persistence.” Chaos, vol. 30, no. 3, 033109, AIP Publishing,
2020, doi:10.1063/1.5122969.
short: G. Yalniz, N.B. Budanur, Chaos 30 (2020).
date_created: 2020-03-04T08:06:25Z
date_published: 2020-03-03T00:00:00Z
date_updated: 2023-08-18T06:47:16Z
day: '03'
department:
- _id: BjHo
doi: 10.1063/1.5122969
external_id:
arxiv:
- '1910.04584'
isi:
- '000519254800002'
intvolume: ' 30'
isi: 1
issue: '3'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1063/1.5122969
month: '03'
oa: 1
oa_version: Published Version
publication: Chaos
publication_identifier:
eissn:
- 1089-7682
issn:
- 1054-1500
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: Inferring symbolic dynamics of chaotic flows from persistence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 30
year: '2020'
...
---
_id: '8043'
abstract:
- lang: eng
text: With decreasing Reynolds number, Re, turbulence in channel flow becomes spatio-temporally
intermittent and self-organises into solitary stripes oblique to the mean flow
direction. We report here the existence of localised nonlinear travelling wave
solutions of the Navier–Stokes equations possessing this obliqueness property.
Such solutions are identified numerically using edge tracking coupled with arclength
continuation. All solutions emerge in saddle-node bifurcations at values of Re
lower than the non-localised solutions. Relative periodic orbit solutions bifurcating
from branches of travelling waves have also been computed. A complete parametric
study is performed, including their stability, the investigation of their large-scale
flow, and the robustness to changes of the numerical domain.
acknowledgement: The authors thank S. Zammert and B. Budanur for useful discussions.
J. F. Gibson is gratefully acknowledged for the development and the maintenance
of the code Channelflow. Y.D. would like to thank P. Schlatter and D. S. Henningson
for an early collaboration on a similar topic in the case of plane Couette flow
during the years 2008–2013.
article_number: A7
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Chaitanya S
full_name: Paranjape, Chaitanya S
id: 3D85B7C4-F248-11E8-B48F-1D18A9856A87
last_name: Paranjape
- first_name: Yohann
full_name: Duguet, Yohann
last_name: Duguet
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Paranjape CS, Duguet Y, Hof B. Oblique stripe solutions of channel flow. Journal
of Fluid Mechanics. 2020;897. doi:10.1017/jfm.2020.322
apa: Paranjape, C. S., Duguet, Y., & Hof, B. (2020). Oblique stripe solutions
of channel flow. Journal of Fluid Mechanics. Cambridge University Press.
https://doi.org/10.1017/jfm.2020.322
chicago: Paranjape, Chaitanya S, Yohann Duguet, and Björn Hof. “Oblique Stripe Solutions
of Channel Flow.” Journal of Fluid Mechanics. Cambridge University Press,
2020. https://doi.org/10.1017/jfm.2020.322.
ieee: C. S. Paranjape, Y. Duguet, and B. Hof, “Oblique stripe solutions of channel
flow,” Journal of Fluid Mechanics, vol. 897. Cambridge University Press,
2020.
ista: Paranjape CS, Duguet Y, Hof B. 2020. Oblique stripe solutions of channel flow.
Journal of Fluid Mechanics. 897, A7.
mla: Paranjape, Chaitanya S., et al. “Oblique Stripe Solutions of Channel Flow.”
Journal of Fluid Mechanics, vol. 897, A7, Cambridge University Press, 2020,
doi:10.1017/jfm.2020.322.
short: C.S. Paranjape, Y. Duguet, B. Hof, Journal of Fluid Mechanics 897 (2020).
date_created: 2020-06-29T07:59:35Z
date_published: 2020-08-25T00:00:00Z
date_updated: 2023-08-22T07:48:02Z
day: '25'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2020.322
external_id:
isi:
- '000539132300001'
file:
- access_level: open_access
checksum: 3f487bf6d9286787096306eaa18702e8
content_type: application/pdf
creator: cziletti
date_created: 2020-06-30T08:37:37Z
date_updated: 2020-07-14T12:48:08Z
file_id: '8070'
file_name: 2020_JournalOfFluidMech_Paranjape.pdf
file_size: 767873
relation: main_file
file_date_updated: 2020-07-14T12:48:08Z
has_accepted_license: '1'
intvolume: ' 897'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-sa/4.0/
month: '08'
oa: 1
oa_version: Published Version
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- '14697645'
issn:
- '00221120'
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Oblique stripe solutions of channel flow
tmp:
image: /images/cc_by_nc_sa.png
legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode
name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC
BY-NC-SA 4.0)
short: CC BY-NC-SA (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 897
year: '2020'
...
---
_id: '8634'
abstract:
- lang: eng
text: In laboratory studies and numerical simulations, we observe clear signatures
of unstable time-periodic solutions in a moderately turbulent quasi-two-dimensional
flow. We validate the dynamical relevance of such solutions by demonstrating that
turbulent flows in both experiment and numerics transiently display time-periodic
dynamics when they shadow unstable periodic orbits (UPOs). We show that UPOs we
computed are also statistically significant, with turbulent flows spending a sizable
fraction of the total time near these solutions. As a result, the average rates
of energy input and dissipation for the turbulent flow and frequently visited
UPOs differ only by a few percent.
acknowledgement: M. F. S. and R. O. G. acknowledge funding from the National Science
Foundation (CMMI-1234436, DMS1125302, CMMI-1725587) and Defense Advanced Research
Projects Agency (HR0011-16-2-0033). B. S.has received funding from the People Programme
(Marie Curie Actions) of the European Union's Seventh Framework Programme FP7/2007–2013/
under REA Grant Agreement No. 291734.
article_number: '064501'
article_processing_charge: No
article_type: original
author:
- first_name: Balachandra
full_name: Suri, Balachandra
id: 47A5E706-F248-11E8-B48F-1D18A9856A87
last_name: Suri
- first_name: Logan
full_name: Kageorge, Logan
last_name: Kageorge
- first_name: Roman O.
full_name: Grigoriev, Roman O.
last_name: Grigoriev
- first_name: Michael F.
full_name: Schatz, Michael F.
last_name: Schatz
citation:
ama: Suri B, Kageorge L, Grigoriev RO, Schatz MF. Capturing turbulent dynamics and
statistics in experiments with unstable periodic orbits. Physical Review Letters.
2020;125(6). doi:10.1103/physrevlett.125.064501
apa: Suri, B., Kageorge, L., Grigoriev, R. O., & Schatz, M. F. (2020). Capturing
turbulent dynamics and statistics in experiments with unstable periodic orbits.
Physical Review Letters. American Physical Society. https://doi.org/10.1103/physrevlett.125.064501
chicago: Suri, Balachandra, Logan Kageorge, Roman O. Grigoriev, and Michael F. Schatz.
“Capturing Turbulent Dynamics and Statistics in Experiments with Unstable Periodic
Orbits.” Physical Review Letters. American Physical Society, 2020. https://doi.org/10.1103/physrevlett.125.064501.
ieee: B. Suri, L. Kageorge, R. O. Grigoriev, and M. F. Schatz, “Capturing turbulent
dynamics and statistics in experiments with unstable periodic orbits,” Physical
Review Letters, vol. 125, no. 6. American Physical Society, 2020.
ista: Suri B, Kageorge L, Grigoriev RO, Schatz MF. 2020. Capturing turbulent dynamics
and statistics in experiments with unstable periodic orbits. Physical Review Letters.
125(6), 064501.
mla: Suri, Balachandra, et al. “Capturing Turbulent Dynamics and Statistics in Experiments
with Unstable Periodic Orbits.” Physical Review Letters, vol. 125, no.
6, 064501, American Physical Society, 2020, doi:10.1103/physrevlett.125.064501.
short: B. Suri, L. Kageorge, R.O. Grigoriev, M.F. Schatz, Physical Review Letters
125 (2020).
date_created: 2020-10-08T17:27:32Z
date_published: 2020-08-05T00:00:00Z
date_updated: 2023-09-05T12:08:29Z
day: '05'
department:
- _id: BjHo
doi: 10.1103/physrevlett.125.064501
ec_funded: 1
external_id:
arxiv:
- '2008.02367'
isi:
- '000555785600005'
intvolume: ' 125'
isi: 1
issue: '6'
keyword:
- General Physics and Astronomy
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2008.02367
month: '08'
oa: 1
oa_version: Preprint
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '291734'
name: International IST Postdoc Fellowship Programme
publication: Physical Review Letters
publication_identifier:
eissn:
- 1079-7114
issn:
- 0031-9007
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
status: public
title: Capturing turbulent dynamics and statistics in experiments with unstable periodic
orbits
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 125
year: '2020'
...
---
_id: '7932'
abstract:
- lang: eng
text: Pulsating flows through tubular geometries are laminar provided that velocities
are moderate. This in particular is also believed to apply to cardiovascular flows
where inertial forces are typically too low to sustain turbulence. On the other
hand, flow instabilities and fluctuating shear stresses are held responsible for
a variety of cardiovascular diseases. Here we report a nonlinear instability mechanism
for pulsating pipe flow that gives rise to bursts of turbulence at low flow rates.
Geometrical distortions of small, yet finite, amplitude are found to excite a
state consisting of helical vortices during flow deceleration. The resulting flow
pattern grows rapidly in magnitude, breaks down into turbulence, and eventually
returns to laminar when the flow accelerates. This scenario causes shear stress
fluctuations and flow reversal during each pulsation cycle. Such unsteady conditions
can adversely affect blood vessels and have been shown to promote inflammation
and dysfunction of the shear stress-sensitive endothelial cell layer.
article_processing_charge: No
article_type: original
author:
- first_name: Duo
full_name: Xu, Duo
id: 3454D55E-F248-11E8-B48F-1D18A9856A87
last_name: Xu
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
- first_name: Xingyu
full_name: Ma, Xingyu
id: 34BADBA6-F248-11E8-B48F-1D18A9856A87
last_name: Ma
orcid: 0000-0002-0179-9737
- first_name: Baofang
full_name: Song, Baofang
last_name: Song
- first_name: Michael
full_name: Riedl, Michael
id: 3BE60946-F248-11E8-B48F-1D18A9856A87
last_name: Riedl
orcid: 0000-0003-4844-6311
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Xu D, Varshney A, Ma X, et al. Nonlinear hydrodynamic instability and turbulence
in pulsatile flow. Proceedings of the National Academy of Sciences of the United
States of America. 2020;117(21):11233-11239. doi:10.1073/pnas.1913716117
apa: Xu, D., Varshney, A., Ma, X., Song, B., Riedl, M., Avila, M., & Hof, B.
(2020). Nonlinear hydrodynamic instability and turbulence in pulsatile flow. Proceedings
of the National Academy of Sciences of the United States of America. National
Academy of Sciences. https://doi.org/10.1073/pnas.1913716117
chicago: Xu, Duo, Atul Varshney, Xingyu Ma, Baofang Song, Michael Riedl, Marc Avila,
and Björn Hof. “Nonlinear Hydrodynamic Instability and Turbulence in Pulsatile
Flow.” Proceedings of the National Academy of Sciences of the United States
of America. National Academy of Sciences, 2020. https://doi.org/10.1073/pnas.1913716117.
ieee: D. Xu et al., “Nonlinear hydrodynamic instability and turbulence in
pulsatile flow,” Proceedings of the National Academy of Sciences of the United
States of America, vol. 117, no. 21. National Academy of Sciences, pp. 11233–11239,
2020.
ista: Xu D, Varshney A, Ma X, Song B, Riedl M, Avila M, Hof B. 2020. Nonlinear hydrodynamic
instability and turbulence in pulsatile flow. Proceedings of the National Academy
of Sciences of the United States of America. 117(21), 11233–11239.
mla: Xu, Duo, et al. “Nonlinear Hydrodynamic Instability and Turbulence in Pulsatile
Flow.” Proceedings of the National Academy of Sciences of the United States
of America, vol. 117, no. 21, National Academy of Sciences, 2020, pp. 11233–39,
doi:10.1073/pnas.1913716117.
short: D. Xu, A. Varshney, X. Ma, B. Song, M. Riedl, M. Avila, B. Hof, Proceedings
of the National Academy of Sciences of the United States of America 117 (2020)
11233–11239.
date_created: 2020-06-07T22:00:51Z
date_published: 2020-05-26T00:00:00Z
date_updated: 2023-11-30T10:55:13Z
day: '26'
department:
- _id: BjHo
doi: 10.1073/pnas.1913716117
ec_funded: 1
external_id:
arxiv:
- '2005.11190'
isi:
- '000536797100014'
intvolume: ' 117'
isi: 1
issue: '21'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2005.11190
month: '05'
oa: 1
oa_version: Preprint
page: 11233-11239
project:
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
call_identifier: FWF
grant_number: I04188
name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Proceedings of the National Academy of Sciences of the United States
of America
publication_identifier:
eissn:
- '10916490'
issn:
- '00278424'
publication_status: published
publisher: National Academy of Sciences
quality_controlled: '1'
related_material:
link:
- description: News on IST Homepage
relation: press_release
url: https://ist.ac.at/en/news/blood-flows-more-turbulent-than-previously-expected/
record:
- id: '12726'
relation: dissertation_contains
status: public
- id: '14530'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Nonlinear hydrodynamic instability and turbulence in pulsatile flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 117
year: '2020'
...
---
_id: '7258'
abstract:
- lang: eng
text: Many flows encountered in nature and applications are characterized by a chaotic
motion known as turbulence. Turbulent flows generate intense friction with pipe
walls and are responsible for considerable amounts of energy losses at world scale.
The nature of turbulent friction and techniques aimed at reducing it have been
subject of extensive research over the last century, but no definite answer has
been found yet. In this thesis we show that in pipes at moderate turbulent Reynolds
numbers friction is better described by the power law first introduced by Blasius
and not by the Prandtl–von Kármán formula. At higher Reynolds numbers, large scale
motions gradually become more important in the flow and can be related to the
change in scaling of friction. Next, we present a series of new techniques that
can relaminarize turbulence by suppressing a key mechanism that regenerates it
at walls, the lift–up effect. In addition, we investigate the process of turbulence
decay in several experiments and discuss the drag reduction potential. Finally,
we examine the behavior of friction under pulsating conditions inspired by the
human heart cycle and we show that under such circumstances turbulent friction
can be reduced to produce energy savings.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
citation:
ama: Scarselli D. New approaches to reduce friction in turbulent pipe flow. 2020.
doi:10.15479/AT:ISTA:7258
apa: Scarselli, D. (2020). New approaches to reduce friction in turbulent pipe
flow. Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:7258
chicago: Scarselli, Davide. “New Approaches to Reduce Friction in Turbulent Pipe
Flow.” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:7258.
ieee: D. Scarselli, “New approaches to reduce friction in turbulent pipe flow,”
Institute of Science and Technology Austria, 2020.
ista: Scarselli D. 2020. New approaches to reduce friction in turbulent pipe flow.
Institute of Science and Technology Austria.
mla: Scarselli, Davide. New Approaches to Reduce Friction in Turbulent Pipe Flow.
Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:7258.
short: D. Scarselli, New Approaches to Reduce Friction in Turbulent Pipe Flow, Institute
of Science and Technology Austria, 2020.
date_created: 2020-01-12T16:07:26Z
date_published: 2020-01-13T00:00:00Z
date_updated: 2023-09-15T12:20:08Z
day: '13'
ddc:
- '532'
degree_awarded: PhD
department:
- _id: BjHo
doi: 10.15479/AT:ISTA:7258
ec_funded: 1
file:
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checksum: 4df1ab24e9896635106adde5a54615bf
content_type: application/zip
creator: dscarsel
date_created: 2020-01-12T15:57:14Z
date_updated: 2021-01-13T23:30:05Z
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file_id: '7259'
file_name: 2020_Scarselli_Thesis.zip
file_size: 26640830
relation: source_file
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creator: dscarsel
date_created: 2020-01-12T15:56:14Z
date_updated: 2021-01-13T23:30:05Z
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file_id: '7260'
file_name: 2020_Scarselli_Thesis.pdf
file_size: 8515844
relation: main_file
file_date_updated: 2021-01-13T23:30:05Z
has_accepted_license: '1'
language:
- iso: eng
month: '01'
oa: 1
oa_version: None
page: '174'
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
- _id: 25104D44-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '737549'
name: Eliminating turbulence in oil pipelines
- _id: 25136C54-B435-11E9-9278-68D0E5697425
grant_number: HO 4393/1-2
name: Experimental studies of the turbulence transition and transport processes
in turbulent Taylor-Couette currents
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '6228'
relation: part_of_dissertation
status: public
- id: '6486'
relation: part_of_dissertation
status: public
- id: '461'
relation: part_of_dissertation
status: public
- id: '422'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: New approaches to reduce friction in turbulent pipe flow
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...
---
_id: '8350'
abstract:
- lang: eng
text: "Cytoplasm is a gel-like crowded environment composed of tens of thousands
of macromolecules, organelles, cytoskeletal networks and cytosol. The structure
of the cytoplasm is thought to be highly organized and heterogeneous due to the
crowding of its constituents and their effective compartmentalization. In such
an environment, the diffusive dynamics of the molecules is very restricted, an
effect that is further amplified by clustering and anchoring of molecules. Despite
the jammed nature of the cytoplasm at the microscopic scale, large-scale reorganization
of cytoplasm is essential for important cellular functions, such as nuclear positioning
and cell division. How such mesoscale reorganization of the cytoplasm is achieved,
especially for very large cells such as oocytes or syncytial tissues that can
span hundreds of micrometers in size, has only begun to be understood.\r\nIn this
thesis, I focus on the recent advances in elucidating the molecular, cellular
and biophysical principles underlying cytoplasmic organization across different
scales, structures and species. First, I outline which of these principles have
been identified by reductionist approaches, such as in vitro reconstitution assays,
where boundary conditions and components can be modulated at ease. I then describe
how the theoretical and experimental framework established in these reduced systems
have been applied to their more complex in vivo counterparts, in particular oocytes
and embryonic syncytial structures, and discuss how such complex biological systems
can initiate symmetry breaking and establish patterning.\r\nSpecifically, I examine
an example of large-scale reorganizations taking place in zebrafish embryos, where
extensive cytoplasmic streaming leads to the segregation of cytoplasm from yolk
granules along the animal-vegetal axis of the embryo. Using biophysical experimentation
and theory, I investigate the forces underlying this process, to show that this
process does not rely on cortical actin reorganization, as previously thought,
but instead on a cell-cycle-dependent bulk actin polymerization wave traveling
from the animal to the vegetal pole of the embryo. This wave functions in segregation
by both pulling cytoplasm animally and pushing yolk granules vegetally. Cytoplasm
pulling is mediated by bulk actin network flows exerting friction forces on the
cytoplasm, while yolk granule pushing is achieved by a mechanism closely resembling
actin comet formation on yolk granules. This study defines a novel role of bulk
actin polymerization waves in embryo polarization via cytoplasmic segregation.
Lastly, I describe the cytoplasmic reorganizations taking place during zebrafish
oocyte maturation, where the initial segregation of the cytoplasm and yolk granules
occurs. Here, I demonstrate a previously uncharacterized wave of microtubule aster
formation, traveling the oocyte along the animal-vegetal axis. Further research
is required to determine the role of such microtubule structures in cytoplasmic
reorganizations therein.\r\nCollectively, these studies provide further evidence
for the coupling between cell cytoskeleton and cell cycle machinery, which can
underlie a core self-organizing mechanism for orchestrating large-scale reorganizations
in a cell-cycle-tunable manner, where the modulations of the force-generating
machinery and cytoplasmic mechanics can be harbored to fulfill cellular functions."
acknowledged_ssus:
- _id: PreCl
- _id: Bio
- _id: EM-Fac
acknowledgement: "I would have had no fish and hence no results without our wonderful
fish facility crew, Verena Mayer, Eva Schlegl, Andreas Mlak and Matthias Nowak.
Special thanks to Verena for being always happy to help and dealing with our chaotic
schedules in the lab. Danke auch, Verena, für deine Geduld, mit mir auf Deutsch
zu sprechen. Das hat mir sehr geholfen.\r\nSpecial thanks to the Bioimaging and
EM facilities at IST Austria for supporting us every day. Very special thanks would
go to Robert Hauschild for his continuous support on data analysis and also to Jack
Merrin for designing and building microfabricated chambers for the project and for
the various discussions on making zebrafish extracts."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Shayan
full_name: Shamipour, Shayan
id: 40B34FE2-F248-11E8-B48F-1D18A9856A87
last_name: Shamipour
citation:
ama: Shamipour S. Bulk actin dynamics drive phase segregation in zebrafish oocytes
. 2020. doi:10.15479/AT:ISTA:8350
apa: Shamipour, S. (2020). Bulk actin dynamics drive phase segregation in zebrafish
oocytes . Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:8350
chicago: Shamipour, Shayan. “Bulk Actin Dynamics Drive Phase Segregation in Zebrafish
Oocytes .” Institute of Science and Technology Austria, 2020. https://doi.org/10.15479/AT:ISTA:8350.
ieee: S. Shamipour, “Bulk actin dynamics drive phase segregation in zebrafish oocytes
,” Institute of Science and Technology Austria, 2020.
ista: Shamipour S. 2020. Bulk actin dynamics drive phase segregation in zebrafish
oocytes . Institute of Science and Technology Austria.
mla: Shamipour, Shayan. Bulk Actin Dynamics Drive Phase Segregation in Zebrafish
Oocytes . Institute of Science and Technology Austria, 2020, doi:10.15479/AT:ISTA:8350.
short: S. Shamipour, Bulk Actin Dynamics Drive Phase Segregation in Zebrafish Oocytes
, Institute of Science and Technology Austria, 2020.
date_created: 2020-09-09T11:12:10Z
date_published: 2020-09-09T00:00:00Z
date_updated: 2023-09-27T14:16:45Z
day: '09'
ddc:
- '570'
degree_awarded: PhD
department:
- _id: BjHo
- _id: CaHe
doi: 10.15479/AT:ISTA:8350
file:
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date_created: 2020-09-09T11:06:27Z
date_updated: 2021-09-11T22:30:05Z
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file_name: Shayan-Thesis-Final.docx
file_size: 65194814
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creator: sshamip
date_created: 2020-09-09T11:06:13Z
date_updated: 2021-09-11T22:30:05Z
embargo: 2021-09-10
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file_size: 23729605
relation: main_file
file_date_updated: 2021-09-11T22:30:05Z
has_accepted_license: '1'
language:
- iso: eng
month: '09'
oa: 1
oa_version: None
page: '107'
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '661'
relation: part_of_dissertation
status: public
- id: '6508'
relation: part_of_dissertation
status: public
- id: '7001'
relation: part_of_dissertation
status: public
- id: '735'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Carl-Philipp J
full_name: Heisenberg, Carl-Philipp J
id: 39427864-F248-11E8-B48F-1D18A9856A87
last_name: Heisenberg
orcid: 0000-0002-0912-4566
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: 'Bulk actin dynamics drive phase segregation in zebrafish oocytes '
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...
---
_id: '5943'
abstract:
- lang: eng
text: The hairpin instability of a jet in a crossflow (JICF) for a low jet-to-crossflow
velocity ratio is investigated experimentally for a velocity ratio range of R
∈ (0.14, 0.75) and crossflow Reynolds numbers ReD ∈ (260, 640). From spectral
analysis we characterize the Strouhal number and amplitude of the hairpin instability
as a function of R and ReD. We demonstrate that the dynamics of the hairpins is
well described by the Landau model, and, hence, that the instability occurs through
Hopf bifurcation, similarly to other hydrodynamical oscillators such as wake behind
different bluff bodies. Using the Landau model, we determine the precise threshold
values of hairpin shedding. We also study the spatial dependence of this hydrodynamical
instability, which shows a global behaviour.
article_processing_charge: No
article_type: original
author:
- first_name: Lukasz
full_name: Klotz, Lukasz
id: 2C9AF1C2-F248-11E8-B48F-1D18A9856A87
last_name: Klotz
orcid: 0000-0003-1740-7635
- first_name: Konrad
full_name: Gumowski, Konrad
last_name: Gumowski
- first_name: José Eduardo
full_name: Wesfreid, José Eduardo
last_name: Wesfreid
citation:
ama: Klotz L, Gumowski K, Wesfreid JE. Experiments on a jet in a crossflow in the
low-velocity-ratio regime. Journal of Fluid Mechanics. 2019;863:386-406.
doi:10.1017/jfm.2018.974
apa: Klotz, L., Gumowski, K., & Wesfreid, J. E. (2019). Experiments on a jet
in a crossflow in the low-velocity-ratio regime. Journal of Fluid Mechanics.
Cambridge University Press. https://doi.org/10.1017/jfm.2018.974
chicago: Klotz, Lukasz, Konrad Gumowski, and José Eduardo Wesfreid. “Experiments
on a Jet in a Crossflow in the Low-Velocity-Ratio Regime.” Journal of Fluid
Mechanics. Cambridge University Press, 2019. https://doi.org/10.1017/jfm.2018.974.
ieee: L. Klotz, K. Gumowski, and J. E. Wesfreid, “Experiments on a jet in a crossflow
in the low-velocity-ratio regime,” Journal of Fluid Mechanics, vol. 863.
Cambridge University Press, pp. 386–406, 2019.
ista: Klotz L, Gumowski K, Wesfreid JE. 2019. Experiments on a jet in a crossflow
in the low-velocity-ratio regime. Journal of Fluid Mechanics. 863, 386–406.
mla: Klotz, Lukasz, et al. “Experiments on a Jet in a Crossflow in the Low-Velocity-Ratio
Regime.” Journal of Fluid Mechanics, vol. 863, Cambridge University Press,
2019, pp. 386–406, doi:10.1017/jfm.2018.974.
short: L. Klotz, K. Gumowski, J.E. Wesfreid, Journal of Fluid Mechanics 863 (2019)
386–406.
date_created: 2019-02-10T22:59:15Z
date_published: 2019-03-25T00:00:00Z
date_updated: 2023-08-24T14:43:13Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2018.974
ec_funded: 1
external_id:
arxiv:
- '1902.07931'
isi:
- '000526029100016'
intvolume: ' 863'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1902.07931
month: '03'
oa: 1
oa_version: Preprint
page: 386-406
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Journal of Fluid Mechanics
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Experiments on a jet in a crossflow in the low-velocity-ratio regime
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 863
year: '2019'
...
---
_id: '5878'
abstract:
- lang: eng
text: We consider the motion of a droplet bouncing on a vibrating bath of the same
fluid in the presence of a central potential. We formulate a rotation symmetry-reduced
description of this system, which allows for the straightforward application of
dynamical systems theory tools. As an illustration of the utility of the symmetry
reduction, we apply it to a model of the pilot-wave system with a central harmonic
force. We begin our analysis by identifying local bifurcations and the onset of
chaos. We then describe the emergence of chaotic regions and their merging bifurcations,
which lead to the formation of a global attractor. In this final regime, the droplet’s
angular momentum spontaneously changes its sign as observed in the experiments
of Perrard et al.
article_number: '013122'
article_processing_charge: No
article_type: original
author:
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Marc
full_name: Fleury, Marc
last_name: Fleury
citation:
ama: 'Budanur NB, Fleury M. State space geometry of the chaotic pilot-wave hydrodynamics.
Chaos: An Interdisciplinary Journal of Nonlinear Science. 2019;29(1). doi:10.1063/1.5058279'
apa: 'Budanur, N. B., & Fleury, M. (2019). State space geometry of the chaotic
pilot-wave hydrodynamics. Chaos: An Interdisciplinary Journal of Nonlinear
Science. AIP Publishing. https://doi.org/10.1063/1.5058279'
chicago: 'Budanur, Nazmi B, and Marc Fleury. “State Space Geometry of the Chaotic
Pilot-Wave Hydrodynamics.” Chaos: An Interdisciplinary Journal of Nonlinear
Science. AIP Publishing, 2019. https://doi.org/10.1063/1.5058279.'
ieee: 'N. B. Budanur and M. Fleury, “State space geometry of the chaotic pilot-wave
hydrodynamics,” Chaos: An Interdisciplinary Journal of Nonlinear Science,
vol. 29, no. 1. AIP Publishing, 2019.'
ista: 'Budanur NB, Fleury M. 2019. State space geometry of the chaotic pilot-wave
hydrodynamics. Chaos: An Interdisciplinary Journal of Nonlinear Science. 29(1),
013122.'
mla: 'Budanur, Nazmi B., and Marc Fleury. “State Space Geometry of the Chaotic Pilot-Wave
Hydrodynamics.” Chaos: An Interdisciplinary Journal of Nonlinear Science,
vol. 29, no. 1, 013122, AIP Publishing, 2019, doi:10.1063/1.5058279.'
short: 'N.B. Budanur, M. Fleury, Chaos: An Interdisciplinary Journal of Nonlinear
Science 29 (2019).'
date_created: 2019-01-23T08:35:09Z
date_published: 2019-01-22T00:00:00Z
date_updated: 2023-08-25T10:16:11Z
day: '22'
department:
- _id: BjHo
doi: 10.1063/1.5058279
external_id:
arxiv:
- '1812.09011'
isi:
- '000457409100028'
intvolume: ' 29'
isi: 1
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1812.09011
month: '01'
oa: 1
oa_version: Preprint
publication: 'Chaos: An Interdisciplinary Journal of Nonlinear Science'
publication_identifier:
eissn:
- 1089-7682
issn:
- 1054-1500
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
related_material:
link:
- relation: erratum
url: https://aip.scitation.org/doi/abs/10.1063/1.5097157
scopus_import: '1'
status: public
title: State space geometry of the chaotic pilot-wave hydrodynamics
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 29
year: '2019'
...
---
_id: '6413'
abstract:
- lang: eng
text: Phase-field methods have long been used to model the flow of immiscible fluids.
Their ability to naturally capture interface topological changes is widely recognized,
but their accuracy in simulating flows of real fluids in practical geometries
is not established. We here quantitatively investigate the convergence of the
phase-field method to the sharp-interface limit with simulations of two-phase
pipe flow. We focus on core-annular flows, in which a highly viscous fluid is
lubricated by a less viscous fluid, and validate our simulations with an analytic
laminar solution, a formal linear stability analysis and also in the fully nonlinear
regime. We demonstrate the ability of the phase-field method to accurately deal
with non-rectangular geometry, strong advection, unsteady fluctuations and large
viscosity contrast. We argue that phase-field methods are very promising for quantitatively
studying moderately turbulent flows, especially at high concentrations of the
disperse phase.
article_processing_charge: No
article_type: original
author:
- first_name: Baofang
full_name: Song, Baofang
last_name: Song
- first_name: Carlos
full_name: Plana, Carlos
last_name: Plana
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
citation:
ama: Song B, Plana C, Lopez Alonso JM, Avila M. Phase-field simulation of core-annular
pipe flow. International Journal of Multiphase Flow. 2019;117:14-24. doi:10.1016/j.ijmultiphaseflow.2019.04.027
apa: Song, B., Plana, C., Lopez Alonso, J. M., & Avila, M. (2019). Phase-field
simulation of core-annular pipe flow. International Journal of Multiphase Flow.
Elsevier. https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027
chicago: Song, Baofang, Carlos Plana, Jose M Lopez Alonso, and Marc Avila. “Phase-Field
Simulation of Core-Annular Pipe Flow.” International Journal of Multiphase
Flow. Elsevier, 2019. https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027.
ieee: B. Song, C. Plana, J. M. Lopez Alonso, and M. Avila, “Phase-field simulation
of core-annular pipe flow,” International Journal of Multiphase Flow, vol.
117. Elsevier, pp. 14–24, 2019.
ista: Song B, Plana C, Lopez Alonso JM, Avila M. 2019. Phase-field simulation of
core-annular pipe flow. International Journal of Multiphase Flow. 117, 14–24.
mla: Song, Baofang, et al. “Phase-Field Simulation of Core-Annular Pipe Flow.” International
Journal of Multiphase Flow, vol. 117, Elsevier, 2019, pp. 14–24, doi:10.1016/j.ijmultiphaseflow.2019.04.027.
short: B. Song, C. Plana, J.M. Lopez Alonso, M. Avila, International Journal of
Multiphase Flow 117 (2019) 14–24.
date_created: 2019-05-13T07:58:35Z
date_published: 2019-08-01T00:00:00Z
date_updated: 2023-08-25T10:19:55Z
day: '01'
department:
- _id: BjHo
doi: 10.1016/j.ijmultiphaseflow.2019.04.027
external_id:
arxiv:
- '1902.07351'
isi:
- '000474496000002'
intvolume: ' 117'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1902.07351
month: '08'
oa: 1
oa_version: Preprint
page: 14-24
publication: International Journal of Multiphase Flow
publication_identifier:
issn:
- '03019322'
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Phase-field simulation of core-annular pipe flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 117
year: '2019'
...
---
_id: '6978'
abstract:
- lang: eng
text: In pipes and channels, the onset of turbulence is initially dominated by localizedtransients, which lead to sustained turbulence through their collective dynamics. In thepresent
work, we study numerically the localized turbulence in pipe flow and elucidate
astate space structure that gives rise to transient chaos. Starting from the basin
boundaryseparating laminar and turbulent flow, we identify transverse homoclinic orbits, thepresence
of which necessitates a homoclinic tangle and chaos. A direct consequence ofthe
homoclinic tangle is the fractal nature of the laminar-turbulent boundary, which
wasconjectured in various earlier studies. By mapping the transverse intersections
between thestable and unstable manifold of a periodic orbit, we identify the gateways
that promote anescape from turbulence.
acknowledged_ssus:
- _id: ScienComp
article_processing_charge: No
article_type: original
author:
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Akshunna
full_name: Dogra, Akshunna
last_name: Dogra
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Budanur NB, Dogra A, Hof B. Geometry of transient chaos in streamwise-localized
pipe flow turbulence. Physical Review Fluids. 2019;4(10):102401. doi:10.1103/PhysRevFluids.4.102401
apa: Budanur, N. B., Dogra, A., & Hof, B. (2019). Geometry of transient chaos
in streamwise-localized pipe flow turbulence. Physical Review Fluids. American
Physical Society. https://doi.org/10.1103/PhysRevFluids.4.102401
chicago: Budanur, Nazmi B, Akshunna Dogra, and Björn Hof. “Geometry of Transient
Chaos in Streamwise-Localized Pipe Flow Turbulence.” Physical Review Fluids.
American Physical Society, 2019. https://doi.org/10.1103/PhysRevFluids.4.102401.
ieee: N. B. Budanur, A. Dogra, and B. Hof, “Geometry of transient chaos in streamwise-localized
pipe flow turbulence,” Physical Review Fluids, vol. 4, no. 10. American
Physical Society, p. 102401, 2019.
ista: Budanur NB, Dogra A, Hof B. 2019. Geometry of transient chaos in streamwise-localized
pipe flow turbulence. Physical Review Fluids. 4(10), 102401.
mla: Budanur, Nazmi B., et al. “Geometry of Transient Chaos in Streamwise-Localized
Pipe Flow Turbulence.” Physical Review Fluids, vol. 4, no. 10, American
Physical Society, 2019, p. 102401, doi:10.1103/PhysRevFluids.4.102401.
short: N.B. Budanur, A. Dogra, B. Hof, Physical Review Fluids 4 (2019) 102401.
date_created: 2019-11-04T10:04:01Z
date_published: 2019-10-01T00:00:00Z
date_updated: 2023-08-30T07:20:03Z
day: '01'
department:
- _id: BjHo
doi: 10.1103/PhysRevFluids.4.102401
external_id:
arxiv:
- '1810.02211'
isi:
- '000493510400001'
intvolume: ' 4'
isi: 1
issue: '10'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1810.02211
month: '10'
oa: 1
oa_version: Preprint
page: '102401'
publication: Physical Review Fluids
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Geometry of transient chaos in streamwise-localized pipe flow turbulence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 4
year: '2019'
...
---
_id: '7397'
abstract:
- lang: eng
text: Polymer additives can substantially reduce the drag of turbulent flows and
the upperlimit, the so called “maximum drag reduction” (MDR) asymptote is universal,
i.e. inde-pendent of the type of polymer and solvent used. Until recently, the
consensus was that,in this limit, flows are in a marginal state where only a minimal
level of turbulence activ-ity persists. Observations in direct numerical simulations
using minimal sized channelsappeared to support this view and reported long “hibernation” periods where turbu-lence
is marginalized. In simulations of pipe flow we find that, indeed, with increasingWeissenberg
number (Wi), turbulence expresses long periods of hibernation if the domainsize
is small. However, with increasing pipe length, the temporal hibernation continuouslyalters
to spatio-temporal intermittency and here the flow consists of turbulent puffs
sur-rounded by laminar flow. Moreover, upon an increase in Wi, the flow fully
relaminarises,in agreement with recent experiments. At even larger Wi, a different
instability is en-countered causing a drag increase towards MDR. Our findings
hence link earlier minimalflow unit simulations with recent experiments and confirm
that the addition of polymersinitially suppresses Newtonian turbulence and leads
to a reverse transition. The MDRstate on the other hand results from a separate
instability and the underlying dynamicscorresponds to the recently proposed state
of elasto-inertial-turbulence (EIT).
article_processing_charge: No
article_type: original
author:
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: George H
full_name: Choueiri, George H
id: 448BD5BC-F248-11E8-B48F-1D18A9856A87
last_name: Choueiri
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Lopez Alonso JM, Choueiri GH, Hof B. Dynamics of viscoelastic pipe flow at
low Reynolds numbers in the maximum drag reduction limit. Journal of Fluid
Mechanics. 2019;874:699-719. doi:10.1017/jfm.2019.486
apa: Lopez Alonso, J. M., Choueiri, G. H., & Hof, B. (2019). Dynamics of viscoelastic
pipe flow at low Reynolds numbers in the maximum drag reduction limit. Journal
of Fluid Mechanics. CUP. https://doi.org/10.1017/jfm.2019.486
chicago: Lopez Alonso, Jose M, George H Choueiri, and Björn Hof. “Dynamics of Viscoelastic
Pipe Flow at Low Reynolds Numbers in the Maximum Drag Reduction Limit.” Journal
of Fluid Mechanics. CUP, 2019. https://doi.org/10.1017/jfm.2019.486.
ieee: J. M. Lopez Alonso, G. H. Choueiri, and B. Hof, “Dynamics of viscoelastic
pipe flow at low Reynolds numbers in the maximum drag reduction limit,” Journal
of Fluid Mechanics, vol. 874. CUP, pp. 699–719, 2019.
ista: Lopez Alonso JM, Choueiri GH, Hof B. 2019. Dynamics of viscoelastic pipe flow
at low Reynolds numbers in the maximum drag reduction limit. Journal of Fluid
Mechanics. 874, 699–719.
mla: Lopez Alonso, Jose M., et al. “Dynamics of Viscoelastic Pipe Flow at Low Reynolds
Numbers in the Maximum Drag Reduction Limit.” Journal of Fluid Mechanics,
vol. 874, CUP, 2019, pp. 699–719, doi:10.1017/jfm.2019.486.
short: J.M. Lopez Alonso, G.H. Choueiri, B. Hof, Journal of Fluid Mechanics 874
(2019) 699–719.
date_created: 2020-01-29T16:05:19Z
date_published: 2019-09-10T00:00:00Z
date_updated: 2023-09-06T15:36:36Z
day: '10'
department:
- _id: BjHo
doi: 10.1017/jfm.2019.486
external_id:
arxiv:
- '1808.04080'
isi:
- '000475349900001'
intvolume: ' 874'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1808.04080
month: '09'
oa: 1
oa_version: Preprint
page: 699-719
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: CUP
quality_controlled: '1'
scopus_import: '1'
status: public
title: Dynamics of viscoelastic pipe flow at low Reynolds numbers in the maximum drag
reduction limit
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 874
year: '2019'
...
---
_id: '6957'
abstract:
- lang: eng
text: "In many shear flows like pipe flow, plane Couette flow, plane Poiseuille
flow, etc. turbulence emerges subcritically. Here, when subjected to strong enough
perturbations, the flow becomes turbulent in spite of the laminar base flow being
linearly stable. The nature of this instability has puzzled the scientific community
for decades. At onset, turbulence appears in localized patches and flows are spatio-temporally
intermittent. In pipe flow the localized turbulent structures are referred to
as puffs and in planar flows like plane Couette and channel flow, patches arise
in the form of localized oblique bands. In this thesis, we study the onset of
turbulence in channel flow in direct numerical simulations from a dynamical system
theory perspective, as well as by performing experiments in a large aspect ratio
channel.\r\n\r\nThe aim of the experimental work is to determine the critical
Reynolds number where turbulence first becomes sustained. Recently, the onset
of turbulence has been described in analogy to absorbing state phase transition
(i.e. directed percolation). In particular, it has been shown that the critical
point can be estimated from the competition between spreading and decay processes.
Here, by performing experiments, we identify the mechanisms underlying turbulence
proliferation in channel flow and find the critical Reynolds number, above which
turbulence becomes sustained. Above the critical point, the continuous growth
at the tip of the stripes outweighs the stochastic shedding of turbulent patches
at the tail and the stripes expand. For growing stripes, the probability to decay
decreases while the probability of stripe splitting increases. Consequently, and
unlike for the puffs in pipe flow, neither of these two processes is time-independent
i.e. memoryless. Coupling between stripe expansion and creation of new stripes
via splitting leads to a significantly lower critical point ($Re_c=670+/-10$)
than most earlier studies suggest. \r\n\r\nWhile the above approach sheds light
on how turbulence first becomes sustained, it provides no insight into the origin
of the stripes themselves. In the numerical part of the thesis we investigate
how turbulent stripes form from invariant solutions of the Navier-Stokes equations.
The origin of these turbulent stripes can be identified by applying concepts from
the dynamical system theory. In doing so, we identify the exact coherent structures
underlying stripes and their bifurcations and how they give rise to the turbulent
attractor in phase space. We first report a family of localized nonlinear traveling
wave solutions of the Navier-Stokes equations in channel flow. These solutions
show structural similarities with turbulent stripes in experiments like obliqueness,
quasi-streamwise streaks and vortices, etc. A parametric study of these traveling
wave solution is performed, with parameters like Reynolds number, stripe tilt
angle and domain size, including the stability of the solutions. These solutions
emerge through saddle-node bifurcations and form a phase space skeleton for the
turbulent stripes observed in the experiments. The lower branches of these TW
solutions at different tilt angles undergo Hopf bifurcation and new solutions
branches of relative periodic orbits emerge. These RPO solutions do not belong
to the same family and therefore the routes to chaos for different angles are
different. \r\n\r\nIn shear flows, turbulence at onset is transient in nature.
\ Consequently,turbulence can not be tracked to lower Reynolds numbers, where
the dynamics may simplify. Before this happens, turbulence becomes short-lived
and laminarizes. In the last part of the thesis, we show that using numerical
simulations we can continue turbulent stripes in channel flow past the 'relaminarization
barrier' all the way to their origin. Here, turbulent stripe dynamics simplifies
and the fluctuations are no longer stochastic and the stripe settles down to a
relative periodic orbit. This relative periodic orbit originates from the aforementioned
traveling wave solutions. Starting from the relative periodic orbit, a small increase
in speed i.e. Reynolds number gives rise to chaos and the attractor dimension
sharply increases in contrast to the classical transition scenario where the instabilities
affect the flow globally and give rise to much more gradual route to turbulence."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Chaitanya S
full_name: Paranjape, Chaitanya S
id: 3D85B7C4-F248-11E8-B48F-1D18A9856A87
last_name: Paranjape
citation:
ama: Paranjape CS. Onset of turbulence in plane Poiseuille flow. 2019. doi:10.15479/AT:ISTA:6957
apa: Paranjape, C. S. (2019). Onset of turbulence in plane Poiseuille flow.
Institute of Science and Technology Austria. https://doi.org/10.15479/AT:ISTA:6957
chicago: Paranjape, Chaitanya S. “Onset of Turbulence in Plane Poiseuille Flow.”
Institute of Science and Technology Austria, 2019. https://doi.org/10.15479/AT:ISTA:6957.
ieee: C. S. Paranjape, “Onset of turbulence in plane Poiseuille flow,” Institute
of Science and Technology Austria, 2019.
ista: Paranjape CS. 2019. Onset of turbulence in plane Poiseuille flow. Institute
of Science and Technology Austria.
mla: Paranjape, Chaitanya S. Onset of Turbulence in Plane Poiseuille Flow.
Institute of Science and Technology Austria, 2019, doi:10.15479/AT:ISTA:6957.
short: C.S. Paranjape, Onset of Turbulence in Plane Poiseuille Flow, Institute of
Science and Technology Austria, 2019.
date_created: 2019-10-22T12:08:43Z
date_published: 2019-10-24T00:00:00Z
date_updated: 2023-09-07T12:53:25Z
day: '24'
ddc:
- '532'
degree_awarded: PhD
department:
- _id: BjHo
doi: 10.15479/AT:ISTA:6957
file:
- access_level: closed
checksum: 7ba298ba0ce7e1d11691af6b8eaf0a0a
content_type: application/zip
creator: cparanjape
date_created: 2019-10-23T09:54:43Z
date_updated: 2020-07-14T12:47:46Z
file_id: '6962'
file_name: Chaitanya_Paranjape_source_files_tex_figures.zip
file_size: 45828099
relation: source_file
- access_level: open_access
checksum: 642697618314e31ac31392da7909c2d9
content_type: application/pdf
creator: cparanjape
date_created: 2019-10-23T10:37:09Z
date_updated: 2020-07-14T12:47:46Z
file_id: '6963'
file_name: Chaitanya_Paranjape_Thesis.pdf
file_size: 19504197
relation: main_file
file_date_updated: 2020-07-14T12:47:46Z
has_accepted_license: '1'
keyword:
- Instabilities
- Turbulence
- Nonlinear dynamics
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: '138'
publication_identifier:
eissn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
status: public
supervisor:
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
title: Onset of turbulence in plane Poiseuille flow
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2019'
...
---
_id: '7197'
abstract:
- lang: eng
text: During bacterial cell division, the tubulin-homolog FtsZ forms a ring-like
structure at the center of the cell. This Z-ring not only organizes the division
machinery, but treadmilling of FtsZ filaments was also found to play a key role
in distributing proteins at the division site. What regulates the architecture,
dynamics and stability of the Z-ring is currently unknown, but FtsZ-associated
proteins are known to play an important role. Here, using an in vitro reconstitution
approach, we studied how the well-conserved protein ZapA affects FtsZ treadmilling
and filament organization into large-scale patterns. Using high-resolution fluorescence
microscopy and quantitative image analysis, we found that ZapA cooperatively increases
the spatial order of the filament network, but binds only transiently to FtsZ
filaments and has no effect on filament length and treadmilling velocity. Together,
our data provides a model for how FtsZ-associated proteins can increase the precision
and stability of the bacterial cell division machinery in a switch-like manner.
acknowledged_ssus:
- _id: LifeSc
- _id: Bio
article_number: '5744'
article_processing_charge: No
article_type: original
author:
- first_name: Paulo R
full_name: Dos Santos Caldas, Paulo R
id: 38FCDB4C-F248-11E8-B48F-1D18A9856A87
last_name: Dos Santos Caldas
orcid: 0000-0001-6730-4461
- first_name: Maria D
full_name: Lopez Pelegrin, Maria D
id: 319AA9CE-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Pelegrin
- first_name: Daniel J. G.
full_name: Pearce, Daniel J. G.
last_name: Pearce
- first_name: Nazmi B
full_name: Budanur, Nazmi B
id: 3EA1010E-F248-11E8-B48F-1D18A9856A87
last_name: Budanur
orcid: 0000-0003-0423-5010
- first_name: Jan
full_name: Brugués, Jan
last_name: Brugués
- first_name: Martin
full_name: Loose, Martin
id: 462D4284-F248-11E8-B48F-1D18A9856A87
last_name: Loose
orcid: 0000-0001-7309-9724
citation:
ama: Dos Santos Caldas PR, Lopez Pelegrin MD, Pearce DJG, Budanur NB, Brugués J,
Loose M. Cooperative ordering of treadmilling filaments in cytoskeletal networks
of FtsZ and its crosslinker ZapA. Nature Communications. 2019;10. doi:10.1038/s41467-019-13702-4
apa: Dos Santos Caldas, P. R., Lopez Pelegrin, M. D., Pearce, D. J. G., Budanur,
N. B., Brugués, J., & Loose, M. (2019). Cooperative ordering of treadmilling
filaments in cytoskeletal networks of FtsZ and its crosslinker ZapA. Nature
Communications. Springer Nature. https://doi.org/10.1038/s41467-019-13702-4
chicago: Dos Santos Caldas, Paulo R, Maria D Lopez Pelegrin, Daniel J. G. Pearce,
Nazmi B Budanur, Jan Brugués, and Martin Loose. “Cooperative Ordering of Treadmilling
Filaments in Cytoskeletal Networks of FtsZ and Its Crosslinker ZapA.” Nature
Communications. Springer Nature, 2019. https://doi.org/10.1038/s41467-019-13702-4.
ieee: P. R. Dos Santos Caldas, M. D. Lopez Pelegrin, D. J. G. Pearce, N. B. Budanur,
J. Brugués, and M. Loose, “Cooperative ordering of treadmilling filaments in cytoskeletal
networks of FtsZ and its crosslinker ZapA,” Nature Communications, vol.
10. Springer Nature, 2019.
ista: Dos Santos Caldas PR, Lopez Pelegrin MD, Pearce DJG, Budanur NB, Brugués J,
Loose M. 2019. Cooperative ordering of treadmilling filaments in cytoskeletal
networks of FtsZ and its crosslinker ZapA. Nature Communications. 10, 5744.
mla: Dos Santos Caldas, Paulo R., et al. “Cooperative Ordering of Treadmilling Filaments
in Cytoskeletal Networks of FtsZ and Its Crosslinker ZapA.” Nature Communications,
vol. 10, 5744, Springer Nature, 2019, doi:10.1038/s41467-019-13702-4.
short: P.R. Dos Santos Caldas, M.D. Lopez Pelegrin, D.J.G. Pearce, N.B. Budanur,
J. Brugués, M. Loose, Nature Communications 10 (2019).
date_created: 2019-12-20T12:22:57Z
date_published: 2019-12-17T00:00:00Z
date_updated: 2023-09-07T13:18:51Z
day: '17'
ddc:
- '570'
department:
- _id: MaLo
- _id: BjHo
doi: 10.1038/s41467-019-13702-4
ec_funded: 1
external_id:
isi:
- '000503009300001'
file:
- access_level: open_access
checksum: a1b44b427ba341383197790d0e8789fa
content_type: application/pdf
creator: dernst
date_created: 2019-12-23T07:34:56Z
date_updated: 2020-07-14T12:47:53Z
file_id: '7208'
file_name: 2019_NatureComm_Caldas.pdf
file_size: 8488733
relation: main_file
file_date_updated: 2020-07-14T12:47:53Z
has_accepted_license: '1'
intvolume: ' 10'
isi: 1
language:
- iso: eng
month: '12'
oa: 1
oa_version: Published Version
project:
- _id: 2595697A-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '679239'
name: Self-Organization of the Bacterial Cell
- _id: 260D98C8-B435-11E9-9278-68D0E5697425
name: Reconstitution of Bacterial Cell Division Using Purified Components
publication: Nature Communications
publication_identifier:
issn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
record:
- id: '8358'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Cooperative ordering of treadmilling filaments in cytoskeletal networks of
FtsZ and its crosslinker ZapA
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 10
year: '2019'
...
---
_id: '6069'
abstract:
- lang: eng
text: Electron transport in two-dimensional conducting materials such as graphene,
with dominant electron–electron interaction, exhibits unusual vortex flow that
leads to a nonlocal current-field relation (negative resistance), distinct from
the classical Ohm’s law. The transport behavior of these materials is best described
by low Reynolds number hydrodynamics, where the constitutive pressure–speed relation
is Stoke’s law. Here we report evidence of such vortices observed in a viscous
flow of Newtonian fluid in a microfluidic device consisting of a rectangular cavity—analogous
to the electronic system. We extend our experimental observations to elliptic
cavities of different eccentricities, and validate them by numerically solving
bi-harmonic equation obtained for the viscous flow with no-slip boundary conditions.
We verify the existence of a predicted threshold at which vortices appear. Strikingly,
we find that a two-dimensional theoretical model captures the essential features
of three-dimensional Stokes flow in experiments.
article_number: '937'
article_processing_charge: No
author:
- first_name: Jonathan
full_name: Mayzel, Jonathan
last_name: Mayzel
- first_name: Victor
full_name: Steinberg, Victor
last_name: Steinberg
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
citation:
ama: Mayzel J, Steinberg V, Varshney A. Stokes flow analogous to viscous electron
current in graphene. Nature Communications. 2019;10. doi:10.1038/s41467-019-08916-5
apa: Mayzel, J., Steinberg, V., & Varshney, A. (2019). Stokes flow analogous
to viscous electron current in graphene. Nature Communications. Springer
Nature. https://doi.org/10.1038/s41467-019-08916-5
chicago: Mayzel, Jonathan, Victor Steinberg, and Atul Varshney. “Stokes Flow Analogous
to Viscous Electron Current in Graphene.” Nature Communications. Springer
Nature, 2019. https://doi.org/10.1038/s41467-019-08916-5.
ieee: J. Mayzel, V. Steinberg, and A. Varshney, “Stokes flow analogous to viscous
electron current in graphene,” Nature Communications, vol. 10. Springer
Nature, 2019.
ista: Mayzel J, Steinberg V, Varshney A. 2019. Stokes flow analogous to viscous
electron current in graphene. Nature Communications. 10, 937.
mla: Mayzel, Jonathan, et al. “Stokes Flow Analogous to Viscous Electron Current
in Graphene.” Nature Communications, vol. 10, 937, Springer Nature, 2019,
doi:10.1038/s41467-019-08916-5.
short: J. Mayzel, V. Steinberg, A. Varshney, Nature Communications 10 (2019).
date_created: 2019-03-05T13:18:30Z
date_published: 2019-02-26T00:00:00Z
date_updated: 2023-09-08T11:39:02Z
day: '26'
ddc:
- '530'
- '532'
department:
- _id: BjHo
doi: 10.1038/s41467-019-08916-5
ec_funded: 1
external_id:
isi:
- '000459704600001'
file:
- access_level: open_access
checksum: 61192fc49e0d44907c2a4fe384e4b97f
content_type: application/pdf
creator: dernst
date_created: 2019-03-05T13:33:04Z
date_updated: 2020-07-14T12:47:18Z
file_id: '6070'
file_name: 2019_NatureComm_Mayzel.pdf
file_size: 2646391
relation: main_file
file_date_updated: 2020-07-14T12:47:18Z
has_accepted_license: '1'
intvolume: ' 10'
isi: 1
language:
- iso: eng
month: '02'
oa: 1
oa_version: Published Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Nature Communications
publication_identifier:
issn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Stokes flow analogous to viscous electron current in graphene
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 10
year: '2019'
...
---
_id: '6014'
abstract:
- lang: eng
text: Speed of sound waves in gases and liquids are governed by the compressibility
of the medium. There exists another type of non-dispersive wave where the wave
speed depends on stress instead of elasticity of the medium. A well-known example
is the Alfven wave, which propagates through plasma permeated by a magnetic field
with the speed determined by magnetic tension. An elastic analogue of Alfven waves
has been predicted in a flow of dilute polymer solution where the elastic stress
of the stretching polymers determines the elastic wave speed. Here we present
quantitative evidence of elastic Alfven waves in elastic turbulence of a viscoelastic
creeping flow between two obstacles in channel flow. The key finding in the experimental
proof is a nonlinear dependence of the elastic wave speed cel on the Weissenberg
number Wi, which deviates from predictions based on a model of linear polymer
elasticity.
article_number: '652'
article_processing_charge: No
article_type: original
author:
- first_name: Atul
full_name: Varshney, Atul
id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
last_name: Varshney
orcid: 0000-0002-3072-5999
- first_name: Victor
full_name: Steinberg, Victor
last_name: Steinberg
citation:
ama: Varshney A, Steinberg V. Elastic alfven waves in elastic turbulence. Nature
Communications. 2019;10. doi:10.1038/s41467-019-08551-0
apa: Varshney, A., & Steinberg, V. (2019). Elastic alfven waves in elastic turbulence.
Nature Communications. Springer Nature. https://doi.org/10.1038/s41467-019-08551-0
chicago: Varshney, Atul, and Victor Steinberg. “Elastic Alfven Waves in Elastic
Turbulence.” Nature Communications. Springer Nature, 2019. https://doi.org/10.1038/s41467-019-08551-0.
ieee: A. Varshney and V. Steinberg, “Elastic alfven waves in elastic turbulence,”
Nature Communications, vol. 10. Springer Nature, 2019.
ista: Varshney A, Steinberg V. 2019. Elastic alfven waves in elastic turbulence.
Nature Communications. 10, 652.
mla: Varshney, Atul, and Victor Steinberg. “Elastic Alfven Waves in Elastic Turbulence.”
Nature Communications, vol. 10, 652, Springer Nature, 2019, doi:10.1038/s41467-019-08551-0.
short: A. Varshney, V. Steinberg, Nature Communications 10 (2019).
date_created: 2019-02-15T07:10:46Z
date_published: 2019-02-08T00:00:00Z
date_updated: 2023-09-08T11:39:54Z
day: '08'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1038/s41467-019-08551-0
ec_funded: 1
external_id:
arxiv:
- '1902.03763'
isi:
- '000458175300001'
file:
- access_level: open_access
checksum: d3acf07eaad95ec040d8e8565fc9ac37
content_type: application/pdf
creator: dernst
date_created: 2019-02-15T07:15:00Z
date_updated: 2020-07-14T12:47:17Z
file_id: '6015'
file_name: 2019_NatureComm_Varshney.pdf
file_size: 1331490
relation: main_file
file_date_updated: 2020-07-14T12:47:17Z
has_accepted_license: '1'
intvolume: ' 10'
isi: 1
language:
- iso: eng
month: '02'
oa: 1
oa_version: Published Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Nature Communications
publication_identifier:
issn:
- 2041-1723
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
scopus_import: '1'
status: public
title: Elastic alfven waves in elastic turbulence
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 10
year: '2019'
...
---
_id: '6779'
abstract:
- lang: eng
text: "Recent studies suggest that unstable recurrent solutions of the Navier-Stokes
equation provide new insights\r\ninto dynamics of turbulent flows. In this study,
we compute an extensive network of dynamical connections\r\nbetween such solutions
in a weakly turbulent quasi-two-dimensional Kolmogorov flow that lies in the inversion
symmetric subspace. In particular, we find numerous isolated heteroclinic connections
between different\r\ntypes of solutions—equilibria, periodic, and quasiperiodic
orbits—as well as continua of connections forming\r\nhigher-dimensional connecting
manifolds. We also compute a homoclinic connection of a periodic orbit and\r\nprovide
strong evidence that the associated homoclinic tangle forms the chaotic repeller
that underpins transient\r\nturbulence in the symmetric subspace."
article_number: '013112'
article_processing_charge: No
article_type: original
author:
- first_name: Balachandra
full_name: Suri, Balachandra
id: 47A5E706-F248-11E8-B48F-1D18A9856A87
last_name: Suri
- first_name: Ravi Kumar
full_name: Pallantla, Ravi Kumar
last_name: Pallantla
- first_name: Michael F.
full_name: Schatz, Michael F.
last_name: Schatz
- first_name: Roman O.
full_name: Grigoriev, Roman O.
last_name: Grigoriev
citation:
ama: Suri B, Pallantla RK, Schatz MF, Grigoriev RO. Heteroclinic and homoclinic
connections in a Kolmogorov-like flow. Physical Review E. 2019;100(1).
doi:10.1103/physreve.100.013112
apa: Suri, B., Pallantla, R. K., Schatz, M. F., & Grigoriev, R. O. (2019). Heteroclinic
and homoclinic connections in a Kolmogorov-like flow. Physical Review E.
American Physical Society. https://doi.org/10.1103/physreve.100.013112
chicago: Suri, Balachandra, Ravi Kumar Pallantla, Michael F. Schatz, and Roman O.
Grigoriev. “Heteroclinic and Homoclinic Connections in a Kolmogorov-like Flow.”
Physical Review E. American Physical Society, 2019. https://doi.org/10.1103/physreve.100.013112.
ieee: B. Suri, R. K. Pallantla, M. F. Schatz, and R. O. Grigoriev, “Heteroclinic
and homoclinic connections in a Kolmogorov-like flow,” Physical Review E,
vol. 100, no. 1. American Physical Society, 2019.
ista: Suri B, Pallantla RK, Schatz MF, Grigoriev RO. 2019. Heteroclinic and homoclinic
connections in a Kolmogorov-like flow. Physical Review E. 100(1), 013112.
mla: Suri, Balachandra, et al. “Heteroclinic and Homoclinic Connections in a Kolmogorov-like
Flow.” Physical Review E, vol. 100, no. 1, 013112, American Physical Society,
2019, doi:10.1103/physreve.100.013112.
short: B. Suri, R.K. Pallantla, M.F. Schatz, R.O. Grigoriev, Physical Review E 100
(2019).
date_created: 2019-08-09T09:40:41Z
date_published: 2019-07-25T00:00:00Z
date_updated: 2024-02-28T13:13:00Z
day: '25'
ddc:
- '532'
department:
- _id: BjHo
doi: 10.1103/physreve.100.013112
ec_funded: 1
external_id:
arxiv:
- '1907.05860'
isi:
- '000477911800012'
intvolume: ' 100'
isi: 1
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1907.05860
month: '07'
oa: 1
oa_version: Preprint
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '291734'
name: International IST Postdoc Fellowship Programme
publication: Physical Review E
publication_identifier:
eissn:
- 2470-0053
issn:
- 2470-0045
publication_status: published
publisher: American Physical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Heteroclinic and homoclinic connections in a Kolmogorov-like flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 100
year: '2019'
...