---
_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: '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: '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
arxiv: 1
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: '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
arxiv: 1
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: '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
arxiv: 1
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
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intvolume: ' 954'
isi: 1
language:
- iso: eng
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: '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: '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: '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:
- id: '12726'
relation: dissertation_contains
status: public
- id: '14530'
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: '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
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intvolume: ' 17'
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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: '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
arxiv: 1
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: '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: '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
arxiv: 1
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: '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: '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: '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
arxiv: 1
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: '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
arxiv: 1
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: '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
arxiv: 1
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: '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: '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
arxiv: 1
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'
...