---
OA_place: publisher
OA_type: hybrid
_id: '19729'
abstract:
- lang: eng
text: 'From anthropogenic litter carried by ocean currents to plant stems travelling
through the atmosphere, geophysical flows are often seeded with elongated, fibre-like
particles. In this study, we used a large-scale laboratory model of a tidal current
– representative of a widespread class of geophysical flows – to investigate the
tumbling motion of long, slender and floating fibres in the complex turbulence
generated by flow interactions with a tidal inlet. Despite the non-stationary,
non-homogeneous and anisotropic nature of this turbulence, we find that long fibres
statistically rotate at the same frequency as eddies of similar size, a phenomenon
called scale selection, which is known to occur in ideal turbulence. Furthermore,
we report that the signal of the instantaneous transverse velocity difference
between the fibre ends changes significantly from the signal produced by the flow
in the fibre surroundings, although the two are statistically equivalent. These
observations have twofold implications. On the one hand, they confirm the reliability
of using the end-to-end velocity signal of rigid fibres to probe the two-point
transverse statistics of the flow, even under realistic conditions: oceanographers
could exploit this observation to measure transverse velocity differences through
elongated floats in the field, where superdiffusion complicates collecting sufficient
data to probe two-point turbulence statistics at a fixed separation effectively.
On the other hand, by addressing the dynamics of inertial range particles floating
in the coastal zone, these observations are crucial to improving our ability to
predict the fate of meso- and macro-litter, a size class that is currently understudied.'
acknowledgement: A.S. expresses thanks for support from the Research Grants Council
of Hong Kong (project IDs 15216422 and C5032-22EF) and from the Research Institute
for Land and Space (RILS) (project ID P0049622). S.B. is funded by the European
Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie
grant agreement (no.101034413).
article_number: A5
article_processing_charge: No
article_type: original
author:
- first_name: Annalisa
full_name: De Leo, Annalisa
last_name: De Leo
- first_name: Stefano
full_name: Brizzolara, Stefano
id: 4bbe33b8-c59a-11ee-a1af-fa33d1ac42c4
last_name: Brizzolara
- first_name: Mattia
full_name: Cavaiola, Mattia
last_name: Cavaiola
- first_name: Junlin
full_name: He, Junlin
last_name: He
- first_name: Alessandro
full_name: Stocchino, Alessandro
last_name: Stocchino
citation:
ama: De Leo A, Brizzolara S, Cavaiola M, He J, Stocchino A. Rigid fibre transport
in a periodic non-homogeneous geophysical turbulent flow. Journal of Fluid
Mechanics. 2025;1011. doi:10.1017/jfm.2025.362
apa: De Leo, A., Brizzolara, S., Cavaiola, M., He, J., & Stocchino, A. (2025).
Rigid fibre transport in a periodic non-homogeneous geophysical turbulent flow.
Journal of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2025.362
chicago: De Leo, Annalisa, Stefano Brizzolara, Mattia Cavaiola, Junlin He, and Alessandro
Stocchino. “Rigid Fibre Transport in a Periodic Non-Homogeneous Geophysical Turbulent
Flow.” Journal of Fluid Mechanics. Cambridge University Press, 2025. https://doi.org/10.1017/jfm.2025.362.
ieee: A. De Leo, S. Brizzolara, M. Cavaiola, J. He, and A. Stocchino, “Rigid fibre
transport in a periodic non-homogeneous geophysical turbulent flow,” Journal
of Fluid Mechanics, vol. 1011. Cambridge University Press, 2025.
ista: De Leo A, Brizzolara S, Cavaiola M, He J, Stocchino A. 2025. Rigid fibre transport
in a periodic non-homogeneous geophysical turbulent flow. Journal of Fluid Mechanics.
1011, A5.
mla: De Leo, Annalisa, et al. “Rigid Fibre Transport in a Periodic Non-Homogeneous
Geophysical Turbulent Flow.” Journal of Fluid Mechanics, vol. 1011, A5,
Cambridge University Press, 2025, doi:10.1017/jfm.2025.362.
short: A. De Leo, S. Brizzolara, M. Cavaiola, J. He, A. Stocchino, Journal of Fluid
Mechanics 1011 (2025).
date_created: 2025-05-25T22:16:46Z
date_published: 2025-05-16T00:00:00Z
date_updated: 2025-09-30T12:38:34Z
day: '16'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2025.362
ec_funded: 1
external_id:
isi:
- '001489159700001'
file:
- access_level: open_access
checksum: f1b0f6a977fdf2d6eb9e16c11d030c0c
content_type: application/pdf
creator: dernst
date_created: 2025-05-28T08:12:07Z
date_updated: 2025-05-28T08:12:07Z
file_id: '19751'
file_name: 2025_JourFluidMech_DeLeo.pdf
file_size: 6415303
relation: main_file
success: 1
file_date_updated: 2025-05-28T08:12:07Z
has_accepted_license: '1'
intvolume: ' 1011'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '05'
oa: 1
oa_version: Published Version
project:
- _id: fc2ed2f7-9c52-11eb-aca3-c01059dda49c
call_identifier: H2020
grant_number: '101034413'
name: 'IST-BRIDGE: International postdoctoral program'
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: Rigid fibre transport in a periodic non-homogeneous geophysical turbulent 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: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 1011
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
_id: '19730'
abstract:
- lang: eng
text: Feigenbaum universality is shown to occur in subcritical shear flows. Our
testing ground is the counter-rotation regime of the Taylor–Couette flow, where
numerical calculations are performed within a small periodic domain. The accurate
computation of up to the seventh period-doubling bifurcation, assisted by a purposely
defined Poincaré section, has enabled us to reproduce the two Feigenbaum universal
constants with unprecedented accuracy in a fluid flow problem. We have further
devised a method to predict the bifurcation diagram up to the accumulation point
of the cascade based on the detailed inspection of just the first few period-doubling
bifurcations. Remarkably, the method is applicable beyond the accumulation point,
with predictions remaining valid, in a statistical sense, for the chaotic dynamics
that follows.
acknowledgement: This research is supported by the Australian Research Council Discovery
Project DP230102188 and the Ministerio de Ciencia, Innovación y Universidades (Agencia
Estatal de Investigación, project nos. PID 2020–114043 GB-I00 (MCIN/AEI/10.13039/501100011033)
and PID 2023–150029NB-I00 (MCIN/AEI/10.13039/501100011033/FEDER, UE). B.W.’s and
R.A.’s research has been funded by the European Union’s Horizon 2020 research and
innovation programme (Marie Skłodowska-Curie Grant Agreement No. 101034413). R.A.
has also been funded by the Austrian Science Fund (FWF) 10.55776/ESP1481224.
article_number: A36
article_processing_charge: Yes (in subscription journal)
article_type: original
author:
- first_name: Baoying
full_name: Wang, Baoying
id: df755ffe-735a-11ee-bb55-dff29d61d338
last_name: Wang
orcid: 0000-0002-6229-0336
- first_name: Roger
full_name: Ayats López, Roger
id: ab77522d-073b-11ed-8aff-e71b39258362
last_name: Ayats López
orcid: 0000-0001-6572-0621
- first_name: K.
full_name: Deguchi, K.
last_name: Deguchi
- first_name: A.
full_name: Meseguer, A.
last_name: Meseguer
- first_name: F.
full_name: Mellibovsky, F.
last_name: Mellibovsky
citation:
ama: Wang B, Ayats López R, Deguchi K, Meseguer A, Mellibovsky F. Feigenbaum universality
in subcritical Taylor-Couette flow. Journal of Fluid Mechanics. 2025;1010.
doi:10.1017/jfm.2025.278
apa: Wang, B., Ayats López, R., Deguchi, K., Meseguer, A., & Mellibovsky, F.
(2025). Feigenbaum universality in subcritical Taylor-Couette flow. Journal
of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2025.278
chicago: Wang, Baoying, Roger Ayats López, K. Deguchi, A. Meseguer, and F. Mellibovsky.
“Feigenbaum Universality in Subcritical Taylor-Couette Flow.” Journal of Fluid
Mechanics. Cambridge University Press, 2025. https://doi.org/10.1017/jfm.2025.278.
ieee: B. Wang, R. Ayats López, K. Deguchi, A. Meseguer, and F. Mellibovsky, “Feigenbaum
universality in subcritical Taylor-Couette flow,” Journal of Fluid Mechanics,
vol. 1010. Cambridge University Press, 2025.
ista: Wang B, Ayats López R, Deguchi K, Meseguer A, Mellibovsky F. 2025. Feigenbaum
universality in subcritical Taylor-Couette flow. Journal of Fluid Mechanics. 1010,
A36.
mla: Wang, Baoying, et al. “Feigenbaum Universality in Subcritical Taylor-Couette
Flow.” Journal of Fluid Mechanics, vol. 1010, A36, Cambridge University
Press, 2025, doi:10.1017/jfm.2025.278.
short: B. Wang, R. Ayats López, K. Deguchi, A. Meseguer, F. Mellibovsky, Journal
of Fluid Mechanics 1010 (2025).
date_created: 2025-05-25T22:16:48Z
date_published: 2025-05-14T00:00:00Z
date_updated: 2025-09-30T12:39:05Z
day: '14'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2025.278
ec_funded: 1
external_id:
isi:
- '001487354900001'
file:
- access_level: open_access
checksum: 77f39b762a0e59e88954afb93b23cc7a
content_type: application/pdf
creator: dernst
date_created: 2025-05-28T08:32:33Z
date_updated: 2025-05-28T08:32:33Z
file_id: '19752'
file_name: 2025_JourFluidMech_Wang.pdf
file_size: 3607069
relation: main_file
success: 1
file_date_updated: 2025-05-28T08:32:33Z
has_accepted_license: '1'
intvolume: ' 1010'
isi: 1
language:
- iso: eng
month: '05'
oa: 1
oa_version: Published Version
project:
- _id: fc2ed2f7-9c52-11eb-aca3-c01059dda49c
call_identifier: H2020
grant_number: '101034413'
name: 'IST-BRIDGE: International postdoctoral program'
- _id: 942a0200-16d5-11f0-9cad-f48ab22dfd1c
grant_number: ESP 1481224
name: Pattern Formation Mechanisms in Planar Shear 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: Feigenbaum universality in subcritical Taylor-Couette flow
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 1010
year: '2025'
...
---
OA_place: publisher
OA_type: hybrid
_id: '19732'
abstract:
- lang: eng
text: The transition to chaos in the subcritical regime of counter-rotating Taylor–Couette
flow is investigated using a minimal periodic domain capable of sustaining coherent
structures. Following a Feigenbaum cascade, the dynamics is found to be remarkably
well approximated by a simple discrete map that admits rigorous proof of its chaotic
nature. The chaotic set that arises for the map features densely distributed periodic
points that are in one-to-one correspondence with unstable periodic orbits (UPOs)
of the Navier–Stokes system. This supports the increasingly accepted view that
UPOs may serve as the backbone of turbulence and, indeed, we demonstrate that
it is possible to reconstruct every statistical property of chaotic fluid flow
from UPOs.
acknowledgement: This research is supported by the Australian Research Council Discovery
Project DP230102188 and the Ministerio de Ciencia, Innovación y Universidades (Agencia
Estatal de Investigación, project nos PID 2020-114043 GB-I00 (MCIN/AEI/10.13039/501100011033)
and PID 2023-150029NB-I00 (MCIN/AEI/10.13039/ 501100011033/FEDER, UE). B.W. and
R.A.’s research has been funded by the European Union’s Horizon 2020 research and
innovation programme (Marie Skłodowska-Curie grant agreement no. 101034413). R.A.
has also been funded by the Austrian Science Fund (FWF) 10.55776/ESP1481224.
article_number: R2
article_processing_charge: Yes (in subscription journal)
article_type: original
author:
- first_name: Baoying
full_name: Wang, Baoying
id: df755ffe-735a-11ee-bb55-dff29d61d338
last_name: Wang
orcid: 0000-0002-6229-0336
- first_name: Roger
full_name: Ayats López, Roger
id: ab77522d-073b-11ed-8aff-e71b39258362
last_name: Ayats López
orcid: 0000-0001-6572-0621
- first_name: K.
full_name: Deguchi, K.
last_name: Deguchi
- first_name: A.
full_name: Meseguer, A.
last_name: Meseguer
- first_name: F.
full_name: Mellibovsky, F.
last_name: Mellibovsky
citation:
ama: Wang B, Ayats López R, Deguchi K, Meseguer A, Mellibovsky F. Mathematically
established chaos and forecast of statistics with recurrent patterns in Taylor-Couette
flow. Journal of Fluid Mechanics. 2025;1011. doi:10.1017/jfm.2025.151
apa: Wang, B., Ayats López, R., Deguchi, K., Meseguer, A., & Mellibovsky, F.
(2025). Mathematically established chaos and forecast of statistics with recurrent
patterns in Taylor-Couette flow. Journal of Fluid Mechanics. Cambridge
University Press. https://doi.org/10.1017/jfm.2025.151
chicago: Wang, Baoying, Roger Ayats López, K. Deguchi, A. Meseguer, and F. Mellibovsky.
“Mathematically Established Chaos and Forecast of Statistics with Recurrent Patterns
in Taylor-Couette Flow.” Journal of Fluid Mechanics. Cambridge University
Press, 2025. https://doi.org/10.1017/jfm.2025.151.
ieee: B. Wang, R. Ayats López, K. Deguchi, A. Meseguer, and F. Mellibovsky, “Mathematically
established chaos and forecast of statistics with recurrent patterns in Taylor-Couette
flow,” Journal of Fluid Mechanics, vol. 1011. Cambridge University Press,
2025.
ista: Wang B, Ayats López R, Deguchi K, Meseguer A, Mellibovsky F. 2025. Mathematically
established chaos and forecast of statistics with recurrent patterns in Taylor-Couette
flow. Journal of Fluid Mechanics. 1011, R2.
mla: Wang, Baoying, et al. “Mathematically Established Chaos and Forecast of Statistics
with Recurrent Patterns in Taylor-Couette Flow.” Journal of Fluid Mechanics,
vol. 1011, R2, Cambridge University Press, 2025, doi:10.1017/jfm.2025.151.
short: B. Wang, R. Ayats López, K. Deguchi, A. Meseguer, F. Mellibovsky, Journal
of Fluid Mechanics 1011 (2025).
date_created: 2025-05-25T22:16:52Z
date_published: 2025-05-13T00:00:00Z
date_updated: 2025-09-30T12:39:44Z
day: '13'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2025.151
ec_funded: 1
external_id:
isi:
- '001486096600001'
file:
- access_level: open_access
checksum: 899df5797844a9e811dffeebe8c05c8e
content_type: application/pdf
creator: dernst
date_created: 2025-05-28T09:00:52Z
date_updated: 2025-05-28T09:00:52Z
file_id: '19754'
file_name: 2025_JourFluidMech_Wang_Ayats.pdf
file_size: 998754
relation: main_file
success: 1
file_date_updated: 2025-05-28T09:00:52Z
has_accepted_license: '1'
intvolume: ' 1011'
isi: 1
language:
- iso: eng
month: '05'
oa: 1
oa_version: Published Version
project:
- _id: fc2ed2f7-9c52-11eb-aca3-c01059dda49c
call_identifier: H2020
grant_number: '101034413'
name: 'IST-BRIDGE: International postdoctoral program'
- _id: 942a0200-16d5-11f0-9cad-f48ab22dfd1c
grant_number: ESP 1481224
name: Pattern Formation Mechanisms in Planar Shear 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: Mathematically established chaos and forecast of statistics with recurrent
patterns in Taylor-Couette flow
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 1011
year: '2025'
...
---
_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
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
- 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).
corr_author: '1'
date_created: 2023-01-08T23:00:53Z
date_published: 2023-01-10T00:00:00Z
date_updated: 2026-04-07T11:47:05Z
day: '10'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2022.1001
external_id:
arxiv:
- '2101.07516'
isi:
- '000903336600001'
file:
- access_level: open_access
checksum: 9224f987caefe5dd85a70814d3cce65c
content_type: application/pdf
creator: dernst
date_created: 2023-02-02T12:34:54Z
date_updated: 2023-02-02T12:34:54Z
file_id: '12489'
file_name: 2023_JourFluidMechanics_Marensi.pdf
file_size: 1931647
relation: main_file
success: 1
file_date_updated: 2023-02-02T12:34:54Z
has_accepted_license: '1'
intvolume: ' 954'
isi: 1
language:
- iso: eng
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
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
related_material:
record:
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relation: dissertation_contains
status: public
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: '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).
corr_author: '1'
date_created: 2023-10-30T09:32:28Z
date_published: 2023-11-10T00:00:00Z
date_updated: 2026-04-07T11:47:05Z
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
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
related_material:
record:
- id: '19684'
relation: dissertation_contains
status: public
scopus_import: '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: '10925'
abstract:
- lang: eng
text: Direct numerical simulations (DNS) of turbulent channel flows up to Reτ≈1000 are
conducted to investigate the three-dimensional (consisting of streamwise wavenumber,
spanwise wavenumber and frequency) spectrum of wall pressure fluctuations. To
develop a predictive model of the wavenumber–frequency spectrum from the wavenumber
spectrum, the time decorrelation mechanisms of wall pressure fluctuations are
investigated. It is discovered that the energy-containing part of the wavenumber–frequency
spectrum of wall pressure fluctuations can be well predicted using a similar random
sweeping model for streamwise velocity fluctuations. To refine the investigation,
we further decompose the spectrum of the total wall pressure fluctuations into
the autospectra of rapid and slow pressure fluctuations, and the cross-spectrum
between them. We focus on evaluating the assumption applied in many predictive
models, that is, the magnitude of the cross-spectrum is negligibly small. The
present DNS shows that neglecting the cross-spectrum causes a maximum error up
to 4.7 dB in the subconvective region for all Reynolds numbers under test. Our
analyses indicate that the approximation of neglecting the cross-spectrum needs
to be applied carefully in the investigations of acoustics at low Mach numbers,
in which the subconvective components of wall pressure fluctuations make important
contributions to the radiated acoustic power.
acknowledgement: This research is supported by the NSFC Basic Science Center Program
for ‘Multiscale Problems in Nonlinear Mechanics’ (no. 11988102), National Key Project
(GJXM92579) and the Strategic Priority Research Program (XDB22040104).
article_number: A39
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Bowen
full_name: Yang, Bowen
id: 71b6ff4b-15b2-11ec-abd3-aef6b028cf7e
last_name: Yang
orcid: 0000-0002-4843-6853
- first_name: Zixuan
full_name: Yang, Zixuan
last_name: Yang
citation:
ama: Yang B, Yang Z. On the wavenumber-frequency spectrum of the wall pressure fluctuations
in turbulent channel flow. Journal of Fluid Mechanics. 2022;937. doi:10.1017/jfm.2022.137
apa: Yang, B., & Yang, Z. (2022). On the wavenumber-frequency spectrum of the
wall pressure fluctuations in turbulent channel flow. Journal of Fluid Mechanics.
Cambridge University Press. https://doi.org/10.1017/jfm.2022.137
chicago: Yang, Bowen, and Zixuan Yang. “On the Wavenumber-Frequency Spectrum of
the Wall Pressure Fluctuations in Turbulent Channel Flow.” Journal of Fluid
Mechanics. Cambridge University Press, 2022. https://doi.org/10.1017/jfm.2022.137.
ieee: B. Yang and Z. Yang, “On the wavenumber-frequency spectrum of the wall pressure
fluctuations in turbulent channel flow,” Journal of Fluid Mechanics, vol.
937. Cambridge University Press, 2022.
ista: Yang B, Yang Z. 2022. On the wavenumber-frequency spectrum of the wall pressure
fluctuations in turbulent channel flow. Journal of Fluid Mechanics. 937, A39.
mla: Yang, Bowen, and Zixuan Yang. “On the Wavenumber-Frequency Spectrum of the
Wall Pressure Fluctuations in Turbulent Channel Flow.” Journal of Fluid Mechanics,
vol. 937, A39, Cambridge University Press, 2022, doi:10.1017/jfm.2022.137.
short: B. Yang, Z. Yang, Journal of Fluid Mechanics 937 (2022).
date_created: 2022-03-27T22:01:45Z
date_published: 2022-04-25T00:00:00Z
date_updated: 2026-06-18T10:46:00Z
day: '25'
ddc:
- '530'
department:
- _id: GradSch
doi: 10.1017/jfm.2022.137
external_id:
arxiv:
- '2201.04702'
isi:
- '000763547000001'
intvolume: ' 937'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1017/jfm.2022.137
month: '04'
oa: 1
oa_version: Published Version
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: On the wavenumber-frequency spectrum of the wall pressure fluctuations in turbulent
channel flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 937
year: '2022'
...
---
_id: '12137'
abstract:
- lang: eng
text: We investigate the local self-sustained process underlying spiral turbulence
in counter-rotating Taylor–Couette flow using a periodic annular domain, shaped
as a parallelogram, two of whose sides are aligned with the cylindrical helix
described by the spiral pattern. The primary focus of the study is placed on the
emergence of drifting–rotating waves (DRW) that capture, in a relatively small
domain, the main features of coherent structures typically observed in developed
turbulence. The transitional dynamics of the subcritical region, far below the
first instability of the laminar circular Couette flow, is determined by the upper
and lower branches of DRW solutions originated at saddle-node bifurcations. The
mechanism whereby these solutions self-sustain, and the chaotic dynamics they
induce, are conspicuously reminiscent of other subcritical shear flows. Remarkably,
the flow properties of DRW persist even as the Reynolds number is increased beyond
the linear stability threshold of the base flow. Simulations in a narrow parallelogram
domain stretched in the azimuthal direction to revolve around the apparatus a
full turn confirm that self-sustained vortices eventually concentrate into a localised
pattern. The resulting statistical steady state satisfactorily reproduces qualitatively,
and to a certain degree also quantitatively, the topology and properties of spiral
turbulence as calculated in a large periodic domain of sufficient aspect ratio
that is representative of the real system.
acknowledgement: "K.D.’s research was supported by an Australian Research Council
Discovery Early Career\r\nResearcher Award (DE170100171). B.W., R.A., F.M. and A.M.
research was supported by the Spanish Ministerio de Economía y Competitivdad (grant
numbers FIS2016-77849-R and FIS2017-85794-P) and Ministerio de Ciencia e Innovación
(grant number PID2020-114043GB-I00) and the Generalitat de Catalunya (grant 2017-SGR-785).
B.W.’s research was also supported by the Chinese Scholarship Council (grant CSC
no. 201806440152)."
article_number: A21
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: B.
full_name: Wang, B.
last_name: Wang
- first_name: Roger
full_name: Ayats López, Roger
id: ab77522d-073b-11ed-8aff-e71b39258362
last_name: Ayats López
orcid: 0000-0001-6572-0621
- first_name: K.
full_name: Deguchi, K.
last_name: Deguchi
- first_name: F.
full_name: Mellibovsky, F.
last_name: Mellibovsky
- first_name: A.
full_name: Meseguer, A.
last_name: Meseguer
citation:
ama: Wang B, Ayats López R, Deguchi K, Mellibovsky F, Meseguer A. Self-sustainment
of coherent structures in counter-rotating Taylor–Couette flow. Journal of
Fluid Mechanics. 2022;951. doi:10.1017/jfm.2022.828
apa: Wang, B., Ayats López, R., Deguchi, K., Mellibovsky, F., & Meseguer, A.
(2022). Self-sustainment of coherent structures in counter-rotating Taylor–Couette
flow. Journal of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2022.828
chicago: Wang, B., Roger Ayats López, K. Deguchi, F. Mellibovsky, and A. Meseguer.
“Self-Sustainment of Coherent Structures in Counter-Rotating Taylor–Couette Flow.”
Journal of Fluid Mechanics. Cambridge University Press, 2022. https://doi.org/10.1017/jfm.2022.828.
ieee: B. Wang, R. Ayats López, K. Deguchi, F. Mellibovsky, and A. Meseguer, “Self-sustainment
of coherent structures in counter-rotating Taylor–Couette flow,” Journal of
Fluid Mechanics, vol. 951. Cambridge University Press, 2022.
ista: Wang B, Ayats López R, Deguchi K, Mellibovsky F, Meseguer A. 2022. Self-sustainment
of coherent structures in counter-rotating Taylor–Couette flow. Journal of Fluid
Mechanics. 951, A21.
mla: Wang, B., et al. “Self-Sustainment of Coherent Structures in Counter-Rotating
Taylor–Couette Flow.” Journal of Fluid Mechanics, vol. 951, A21, Cambridge
University Press, 2022, doi:10.1017/jfm.2022.828.
short: B. Wang, R. Ayats López, K. Deguchi, F. Mellibovsky, A. Meseguer, Journal
of Fluid Mechanics 951 (2022).
date_created: 2023-01-12T12:04:17Z
date_published: 2022-11-07T00:00:00Z
date_updated: 2023-08-04T08:54:16Z
day: '07'
department:
- _id: BjHo
doi: 10.1017/jfm.2022.828
external_id:
arxiv:
- '2207.12990'
isi:
- '000879446900001'
intvolume: ' 951'
isi: 1
keyword:
- Mechanical Engineering
- Mechanics of Materials
- Condensed Matter Physics
- Applied Mathematics
language:
- iso: eng
main_file_link:
- open_access: '1'
url: ' https://doi.org/10.48550/arXiv.2207.12990'
month: '11'
oa: 1
oa_version: Preprint
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Self-sustainment of coherent structures in counter-rotating Taylor–Couette
flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 951
year: '2022'
...
---
_id: '9207'
abstract:
- lang: eng
text: "In this paper we experimentally study the transitional range of Reynolds
numbers in\r\nplane Couette–Poiseuille flow, focusing our attention on the localized
turbulent structures\r\ntriggered by a strong impulsive jet and the large-scale
flow generated around these\r\nstructures. We present a detailed investigation
of the large-scale flow and show how\r\nits amplitude depends on Reynolds number
and amplitude perturbation. In addition,\r\nwe characterize the initial dynamics
of the localized turbulent spot, which includes the\r\ncoupling between the small
and large scales, as well as the dependence of the advection\r\nspeed on the large-scale
flow generated around the spot. Finally, we provide the first\r\nexperimental
measurements of the large-scale flow around an oblique turbulent band."
acknowledgement: "We thank Y. Duguet, S. Gomé, G. Lemoult, T. Liu, B. Semin and L.S.
Tuckerman for\r\nfruitful discussions. \r\nThis work was supported by a grant, TRANSFLOW,
provided by the Agence Nationale de\r\nla Recherche (ANR). A.M.P. was partially
supported by the French Embassy in Russia (I.I. Mechnikov scholarship) and by the
Russian Science Foundation (project no. 18-79-00189). L.K. was partially supported
by the European Union’s Horizon 2020 research and innovation programme under the
Marie Skłodowska-Curie grant agreement no. 754411."
article_number: A24
article_processing_charge: Yes (via OA deal)
article_type: original
author:
- first_name: Lukasz
full_name: Klotz, Lukasz
id: 2C9AF1C2-F248-11E8-B48F-1D18A9856A87
last_name: Klotz
orcid: 0000-0003-1740-7635
- first_name: A. M.
full_name: Pavlenko, A. M.
last_name: Pavlenko
- first_name: J. E.
full_name: Wesfreid, J. E.
last_name: Wesfreid
citation:
ama: 'Klotz L, Pavlenko AM, Wesfreid JE. Experimental measurements in plane Couette-Poiseuille
flow: Dynamics of the large- and small-scale flow. Journal of Fluid Mechanics.
2021;912. doi:10.1017/jfm.2020.1089'
apa: 'Klotz, L., Pavlenko, A. M., & Wesfreid, J. E. (2021). Experimental measurements
in plane Couette-Poiseuille flow: Dynamics of the large- and small-scale flow.
Journal of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2020.1089'
chicago: 'Klotz, Lukasz, A. M. Pavlenko, and J. E. Wesfreid. “Experimental Measurements
in Plane Couette-Poiseuille Flow: Dynamics of the Large- and Small-Scale Flow.”
Journal of Fluid Mechanics. Cambridge University Press, 2021. https://doi.org/10.1017/jfm.2020.1089.'
ieee: 'L. Klotz, A. M. Pavlenko, and J. E. Wesfreid, “Experimental measurements
in plane Couette-Poiseuille flow: Dynamics of the large- and small-scale flow,”
Journal of Fluid Mechanics, vol. 912. Cambridge University Press, 2021.'
ista: 'Klotz L, Pavlenko AM, Wesfreid JE. 2021. Experimental measurements in plane
Couette-Poiseuille flow: Dynamics of the large- and small-scale flow. Journal
of Fluid Mechanics. 912, A24.'
mla: 'Klotz, Lukasz, et al. “Experimental Measurements in Plane Couette-Poiseuille
Flow: Dynamics of the Large- and Small-Scale Flow.” Journal of Fluid Mechanics,
vol. 912, A24, Cambridge University Press, 2021, doi:10.1017/jfm.2020.1089.'
short: L. Klotz, A.M. Pavlenko, J.E. Wesfreid, Journal of Fluid Mechanics 912 (2021).
date_created: 2021-02-28T23:01:25Z
date_published: 2021-02-15T00:00:00Z
date_updated: 2025-04-14T07:43:51Z
day: '15'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2020.1089
ec_funded: 1
external_id:
isi:
- '000618034400001'
file:
- access_level: open_access
checksum: b8020d6338667673e34fde0608913dd2
content_type: application/pdf
creator: dernst
date_created: 2021-03-03T09:49:34Z
date_updated: 2021-03-03T09:49:34Z
file_id: '9220'
file_name: 2021_JourFluidMechanics_Klotz.pdf
file_size: 4124471
relation: main_file
success: 1
file_date_updated: 2021-03-03T09:49:34Z
has_accepted_license: '1'
intvolume: ' 912'
isi: 1
language:
- iso: eng
month: '02'
oa: 1
oa_version: Published Version
project:
- _id: 260C2330-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '754411'
name: ISTplus - Postdoctoral Fellowships
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Experimental measurements in plane Couette-Poiseuille flow: Dynamics of the
large- and small-scale flow'
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 912
year: '2021'
...
---
_id: '9297'
abstract:
- lang: eng
text: 'We report the results of an experimental investigation into the decay of
turbulence in plane Couette–Poiseuille flow using ‘quench’ experiments where the
flow laminarises after a sudden reduction in Reynolds number Re. Specifically,
we study the velocity field in the streamwise–spanwise plane. We show that the
spanwise velocity containing rolls decays faster than the streamwise velocity,
which displays elongated regions of higher or lower velocity called streaks. At
final Reynolds numbers above 425, the decay of streaks displays two stages: first
a slow decay when rolls are present and secondly a more rapid decay of streaks
alone. The difference in behaviour results from the regeneration of streaks by
rolls, called the lift-up effect. We define the turbulent fraction as the portion
of the flow containing turbulence and this is estimated by thresholding the spanwise
velocity component. It decreases linearly with time in the whole range of final
Re. The corresponding decay slope increases linearly with final Re. The extrapolated
value at which this decay slope vanishes is Reaz≈656±10, close to Reg≈670 at which
turbulence is self-sustained. The decay of the energy computed from the spanwise
velocity component is found to be exponential. The corresponding decay rate increases
linearly with Re, with an extrapolated vanishing value at ReAz≈688±10. This value
is also close to the value at which the turbulence is self-sustained, showing
that valuable information on the transition can be obtained over a wide range
of Re.'
acknowledgement: "We gratefully acknowledge Joran Rolland, Yohann Duguet, Romain Monchaux,
S´ebastien Gom´e, Laurette Tuckerman, Dwight Barkley, Olivier Dauchot and Sabine
Bottin for fruitful discussions. We thank Xavier Benoit-Gonin, Amaury Fourgeaud,
Thierry Darnige, Olivier Brouard and Justine Laurent for technical help. This work
has benefited from the ANR TransFlow, and by starting grants obtained by B.S. from
CNRS (INSIS) and ESPCI. T.M. was\r\nsupported by a Joliot visiting professorship
grant from ESPCI."
article_number: A65
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: T.
full_name: Liu, T.
last_name: Liu
- first_name: B.
full_name: Semin, B.
last_name: Semin
- first_name: Lukasz
full_name: Klotz, Lukasz
id: 2C9AF1C2-F248-11E8-B48F-1D18A9856A87
last_name: Klotz
orcid: 0000-0003-1740-7635
- first_name: R.
full_name: Godoy-Diana, R.
last_name: Godoy-Diana
- first_name: J. E.
full_name: Wesfreid, J. E.
last_name: Wesfreid
- first_name: T.
full_name: Mullin, T.
last_name: Mullin
citation:
ama: Liu T, Semin B, Klotz L, Godoy-Diana R, Wesfreid JE, Mullin T. Decay of streaks
and rolls in plane Couette-Poiseuille flow. Journal of Fluid Mechanics.
2021;915. doi:10.1017/jfm.2021.89
apa: Liu, T., Semin, B., Klotz, L., Godoy-Diana, R., Wesfreid, J. E., & Mullin,
T. (2021). Decay of streaks and rolls in plane Couette-Poiseuille flow. Journal
of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2021.89
chicago: Liu, T., B. Semin, Lukasz Klotz, R. Godoy-Diana, J. E. Wesfreid, and T.
Mullin. “Decay of Streaks and Rolls in Plane Couette-Poiseuille Flow.” Journal
of Fluid Mechanics. Cambridge University Press, 2021. https://doi.org/10.1017/jfm.2021.89.
ieee: T. Liu, B. Semin, L. Klotz, R. Godoy-Diana, J. E. Wesfreid, and T. Mullin,
“Decay of streaks and rolls in plane Couette-Poiseuille flow,” Journal of Fluid
Mechanics, vol. 915. Cambridge University Press, 2021.
ista: Liu T, Semin B, Klotz L, Godoy-Diana R, Wesfreid JE, Mullin T. 2021. Decay
of streaks and rolls in plane Couette-Poiseuille flow. Journal of Fluid Mechanics.
915, A65.
mla: Liu, T., et al. “Decay of Streaks and Rolls in Plane Couette-Poiseuille Flow.”
Journal of Fluid Mechanics, vol. 915, A65, Cambridge University Press,
2021, doi:10.1017/jfm.2021.89.
short: T. Liu, B. Semin, L. Klotz, R. Godoy-Diana, J.E. Wesfreid, T. Mullin, Journal
of Fluid Mechanics 915 (2021).
date_created: 2021-03-28T22:01:42Z
date_published: 2021-03-17T00:00:00Z
date_updated: 2023-08-07T14:30:11Z
day: '17'
department:
- _id: BjHo
doi: 10.1017/jfm.2021.89
external_id:
arxiv:
- '2008.08851'
isi:
- '000629677500001'
intvolume: ' 915'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/2008.08851
month: '03'
oa: 1
oa_version: Preprint
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Decay of streaks and rolls in plane Couette-Poiseuille flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 915
year: '2021'
...
---
_id: '9467'
abstract:
- lang: eng
text: "Turbulence in the flow of fluid through a pipe can be suppressed by buoyancy
forces. As the suppression of turbulence leads to severe heat transfer deterioration,
this is an important and undesirable phenomenon in both heating and cooling applications.
Vertical flow is often considered, as the axial buoyancy force can help drive
the flow. With heating measured by the buoyancy parameter \U0001D436, our direct
numerical simulations show that shear-driven turbulence may either be completely
laminarised or it transitions to a relatively quiescent convection-driven state.
Buoyancy forces cause a flattening of the base flow profile, which in isothermal
pipe flow has recently been linked to complete suppression of turbulence (Kühnen
et al., Nat. Phys., vol. 14, 2018, pp. 386–390), and the flattened laminar base
profile has enhanced nonlinear stability (Marensi et al., J. Fluid Mech., vol.
863, 2019, pp. 50–875). In agreement with these findings, the nonlinear lower-branch
travelling-wave solution analysed here, which is believed to mediate transition
to turbulence in isothermal pipe flow, is shown to be suppressed by buoyancy.
A linear instability of the laminar base flow is responsible for the appearance
of the relatively quiescent convection driven state for \U0001D436≳4 across the
range of Reynolds numbers considered. In the suppression of turbulence, however,
i.e. in the transition from turbulence, we find clearer association with the analysis
of He et al. (J. Fluid Mech., vol. 809, 2016, pp. 31–71) than with the above dynamical
systems approach, which describes better the transition to turbulence. The laminarisation
criterion He et al. propose, based on an apparent Reynolds number of the flow
as measured by its driving pressure gradient, is found to capture the critical
\U0001D436=\U0001D436\U0001D450\U0001D45F(\U0001D445\U0001D452) above which the
flow will be laminarised or switch to the convection-driven type. Our analysis
suggests that it is the weakened rolls, rather than the streaks, which appear
to be critical for laminarisation."
acknowledgement: The anonymous referees are kindly acknowledged for their useful suggestions
andcomments.
article_number: A17
article_processing_charge: Yes (via OA deal)
article_type: original
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: Shuisheng
full_name: He, Shuisheng
last_name: He
- first_name: Ashley P.
full_name: Willis, Ashley P.
last_name: Willis
citation:
ama: Marensi E, He S, Willis AP. Suppression of turbulence and travelling waves
in a vertical heated pipe. Journal of Fluid Mechanics. 2021;919. doi:10.1017/jfm.2021.371
apa: Marensi, E., He, S., & Willis, A. P. (2021). Suppression of turbulence
and travelling waves in a vertical heated pipe. Journal of Fluid Mechanics.
Cambridge University Press. https://doi.org/10.1017/jfm.2021.371
chicago: Marensi, Elena, Shuisheng He, and Ashley P. Willis. “Suppression of Turbulence
and Travelling Waves in a Vertical Heated Pipe.” Journal of Fluid Mechanics.
Cambridge University Press, 2021. https://doi.org/10.1017/jfm.2021.371.
ieee: E. Marensi, S. He, and A. P. Willis, “Suppression of turbulence and travelling
waves in a vertical heated pipe,” Journal of Fluid Mechanics, vol. 919.
Cambridge University Press, 2021.
ista: Marensi E, He S, Willis AP. 2021. Suppression of turbulence and travelling
waves in a vertical heated pipe. Journal of Fluid Mechanics. 919, A17.
mla: Marensi, Elena, et al. “Suppression of Turbulence and Travelling Waves in a
Vertical Heated Pipe.” Journal of Fluid Mechanics, vol. 919, A17, Cambridge
University Press, 2021, doi:10.1017/jfm.2021.371.
short: E. Marensi, S. He, A.P. Willis, Journal of Fluid Mechanics 919 (2021).
corr_author: '1'
date_created: 2021-06-06T22:01:30Z
date_published: 2021-07-25T00:00:00Z
date_updated: 2025-07-10T12:01:47Z
day: '25'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2021.371
external_id:
arxiv:
- '2008.13486'
isi:
- '000653785000001'
file:
- access_level: open_access
checksum: 867ad077e45c181c2c5ec1311ba27c41
content_type: application/pdf
creator: kschuh
date_created: 2021-08-03T09:53:28Z
date_updated: 2021-08-03T09:53:28Z
file_id: '9766'
file_name: 2021_JournalFluidMechanics_Marensi.pdf
file_size: 4087358
relation: main_file
success: 1
file_date_updated: 2021-08-03T09:53:28Z
has_accepted_license: '1'
intvolume: ' 919'
isi: 1
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Suppression of turbulence and travelling waves in a vertical heated pipe
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 919
year: '2021'
...
---
_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).
corr_author: '1'
date_created: 2020-06-29T07:59:35Z
date_published: 2020-08-25T00:00:00Z
date_updated: 2025-07-10T11:55:03Z
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:
- 1469-7645
issn:
- 0022-1120
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: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 897
year: '2020'
...
---
_id: '7397'
abstract:
- lang: eng
text: Polymer additives can substantially reduce the drag of turbulent flows and
the upperlimit, the so called “maximum drag reduction” (MDR) asymptote is universal,
i.e. inde-pendent of the type of polymer and solvent used. Until recently, the
consensus was that,in this limit, flows are in a marginal state where only a minimal
level of turbulence activ-ity persists. Observations in direct numerical simulations
using minimal sized channelsappeared to support this view and reported long “hibernation” periods where turbu-lence
is marginalized. In simulations of pipe flow we find that, indeed, with increasingWeissenberg
number (Wi), turbulence expresses long periods of hibernation if the domainsize
is small. However, with increasing pipe length, the temporal hibernation continuouslyalters
to spatio-temporal intermittency and here the flow consists of turbulent puffs
sur-rounded by laminar flow. Moreover, upon an increase in Wi, the flow fully
relaminarises,in agreement with recent experiments. At even larger Wi, a different
instability is en-countered causing a drag increase towards MDR. Our findings
hence link earlier minimalflow unit simulations with recent experiments and confirm
that the addition of polymersinitially suppresses Newtonian turbulence and leads
to a reverse transition. The MDRstate on the other hand results from a separate
instability and the underlying dynamicscorresponds to the recently proposed state
of elasto-inertial-turbulence (EIT).
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: George H
full_name: Choueiri, George H
id: 448BD5BC-F248-11E8-B48F-1D18A9856A87
last_name: Choueiri
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Lopez Alonso JM, Choueiri GH, Hof B. Dynamics of viscoelastic pipe flow at
low Reynolds numbers in the maximum drag reduction limit. Journal of Fluid
Mechanics. 2019;874:699-719. doi:10.1017/jfm.2019.486
apa: Lopez Alonso, J. M., Choueiri, G. H., & Hof, B. (2019). Dynamics of viscoelastic
pipe flow at low Reynolds numbers in the maximum drag reduction limit. Journal
of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2019.486
chicago: Lopez Alonso, Jose M, George H Choueiri, and Björn Hof. “Dynamics of Viscoelastic
Pipe Flow at Low Reynolds Numbers in the Maximum Drag Reduction Limit.” Journal
of Fluid Mechanics. Cambridge University Press, 2019. https://doi.org/10.1017/jfm.2019.486.
ieee: J. M. Lopez Alonso, G. H. Choueiri, and B. Hof, “Dynamics of viscoelastic
pipe flow at low Reynolds numbers in the maximum drag reduction limit,” Journal
of Fluid Mechanics, vol. 874. Cambridge University Press, pp. 699–719, 2019.
ista: Lopez Alonso JM, Choueiri GH, Hof B. 2019. Dynamics of viscoelastic pipe flow
at low Reynolds numbers in the maximum drag reduction limit. Journal of Fluid
Mechanics. 874, 699–719.
mla: Lopez Alonso, Jose M., et al. “Dynamics of Viscoelastic Pipe Flow at Low Reynolds
Numbers in the Maximum Drag Reduction Limit.” Journal of Fluid Mechanics,
vol. 874, Cambridge University Press, 2019, pp. 699–719, doi:10.1017/jfm.2019.486.
short: J.M. Lopez Alonso, G.H. Choueiri, B. Hof, Journal of Fluid Mechanics 874
(2019) 699–719.
date_created: 2020-01-29T16:05:19Z
date_published: 2019-09-10T00:00:00Z
date_updated: 2025-05-14T11:21:59Z
day: '10'
department:
- _id: BjHo
doi: 10.1017/jfm.2019.486
external_id:
arxiv:
- '1808.04080'
isi:
- '000475349900001'
intvolume: ' 874'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1808.04080
month: '09'
oa: 1
oa_version: Preprint
page: 699-719
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Dynamics of viscoelastic pipe flow at low Reynolds numbers in the maximum drag
reduction limit
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 874
year: '2019'
...
---
_id: '6228'
abstract:
- lang: eng
text: Following the recent observation that turbulent pipe flow can be relaminarised bya relatively simple modification of the mean velocity profile, we here carry out aquantitative experimental investigation of this phenomenon. Our study confirms thata flat velocity profile leads to a collapse of turbulence and in order to achieve theblunted profile shape, we employ a moving pipe segment that is briefly and rapidlyshifted in the streamwise direction. The relaminarisation threshold and the minimumshift length and speeds are determined as a function of Reynolds number. Althoughturbulence is still active after the acceleration phase, the modulated profile possessesa severely decreased lift-up potential as measured by transient growth. As shown,this results in an exponential decay of fluctuations and the flow relaminarises. Whilethis method can be easily applied at low to moderate flow speeds, the minimumstreamwise length over which the acceleration needs to act increases linearly with theReynolds number.
article_processing_charge: No
arxiv: 1
author:
- first_name: Davide
full_name: Scarselli, Davide
id: 40315C30-F248-11E8-B48F-1D18A9856A87
last_name: Scarselli
orcid: 0000-0001-5227-4271
- first_name: Jakob
full_name: Kühnen, Jakob
id: 3A47AE32-F248-11E8-B48F-1D18A9856A87
last_name: Kühnen
orcid: 0000-0003-4312-0179
- 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, Kühnen J, Hof B. Relaminarising pipe flow by wall movement. Journal
of Fluid Mechanics. 2019;867:934-948. doi:10.1017/jfm.2019.191
apa: Scarselli, D., Kühnen, J., & Hof, B. (2019). Relaminarising pipe flow by
wall movement. Journal of Fluid Mechanics. Cambridge University Press.
https://doi.org/10.1017/jfm.2019.191
chicago: Scarselli, Davide, Jakob Kühnen, and Björn Hof. “Relaminarising Pipe Flow
by Wall Movement.” Journal of Fluid Mechanics. Cambridge University Press,
2019. https://doi.org/10.1017/jfm.2019.191.
ieee: D. Scarselli, J. Kühnen, and B. Hof, “Relaminarising pipe flow by wall movement,”
Journal of Fluid Mechanics, vol. 867. Cambridge University Press, pp. 934–948,
2019.
ista: Scarselli D, Kühnen J, Hof B. 2019. Relaminarising pipe flow by wall movement.
Journal of Fluid Mechanics. 867, 934–948.
mla: Scarselli, Davide, et al. “Relaminarising Pipe Flow by Wall Movement.” Journal
of Fluid Mechanics, vol. 867, Cambridge University Press, 2019, pp. 934–48,
doi:10.1017/jfm.2019.191.
short: D. Scarselli, J. Kühnen, B. Hof, Journal of Fluid Mechanics 867 (2019) 934–948.
date_created: 2019-04-07T21:59:14Z
date_published: 2019-05-25T00:00:00Z
date_updated: 2026-07-15T22:31:08Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2019.191
ec_funded: 1
external_id:
arxiv:
- '1807.05357'
isi:
- '000462606100001'
intvolume: ' 867'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1807.05357
month: '05'
oa: 1
oa_version: Preprint
page: 934-948
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
- _id: 25104D44-B435-11E9-9278-68D0E5697425
call_identifier: H2020
grant_number: '737549'
name: Eliminating turbulence in oil pipelines
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- 1469-7645
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
related_material:
link:
- relation: supplementary_material
url: https://doi.org/10.1017/jfm.2019.191
record:
- id: '7258'
relation: dissertation_contains
status: public
scopus_import: '1'
status: public
title: Relaminarising pipe flow by wall movement
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 867
year: '2019'
...
---
_id: '5996'
abstract:
- lang: eng
text: 'In pipes, turbulence sets in despite the linear stability of the laminar
Hagen–Poiseuille flow. The Reynolds number ( ) for which turbulence first appears
in a given experiment – the ‘natural transition point’ – depends on imperfections
of the set-up, or, more precisely, on the magnitude of finite amplitude perturbations.
At onset, turbulence typically only occupies a certain fraction of the flow, and
this fraction equally is found to differ from experiment to experiment. Despite
these findings, Reynolds proposed that after sufficiently long times, flows may
settle to steady conditions: below a critical velocity, flows should (regardless
of initial conditions) always return to laminar, while above this velocity, eddying
motion should persist. As will be shown, even in pipes several thousand diameters
long, the spatio-temporal intermittent flow patterns observed at the end of the
pipe strongly depend on the initial conditions, and there is no indication that
different flow patterns would eventually settle to a (statistical) steady state.
Exploiting the fact that turbulent puffs do not age (i.e. they are memoryless),
we continuously recreate the puff sequence exiting the pipe at the pipe entrance,
and in doing so introduce periodic boundary conditions for the puff pattern. This
procedure allows us to study the evolution of the flow patterns for arbitrary
long times, and we find that after times in excess of advective time units, indeed
a statistical steady state is reached. Although the resulting flows remain spatio-temporally
intermittent, puff splitting and decay rates eventually reach a balance, so that
the turbulent fraction fluctuates around a well-defined level which only depends
on . In accordance with Reynolds’ proposition, we find that at lower (here 2020),
flows eventually always resume to laminar, while for higher ( ), turbulence persists.
The critical point for pipe flow hence falls in the interval of $2020 , which
is in very good agreement with the recently proposed value of . The latter estimate
was based on single-puff statistics and entirely neglected puff interactions.
Unlike in typical contact processes where such interactions strongly affect the
percolation threshold, in pipe flow, the critical point is only marginally influenced.
Interactions, on the other hand, are responsible for the approach to the statistical
steady state. As shown, they strongly affect the resulting flow patterns, where
they cause ‘puff clustering’, and these regions of large puff densities are observed
to travel across the puff pattern in a wave-like fashion.'
acknowledgement: ' We also thank Philipp Maier and the IST Austria workshop for theirdedicated
technical support'
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Mukund
full_name: Vasudevan, Mukund
id: 3C5A959A-F248-11E8-B48F-1D18A9856A87
last_name: Vasudevan
- first_name: Björn
full_name: Hof, Björn
id: 3A374330-F248-11E8-B48F-1D18A9856A87
last_name: Hof
orcid: 0000-0003-2057-2754
citation:
ama: Vasudevan M, Hof B. The critical point of the transition to turbulence in pipe
flow. Journal of Fluid Mechanics. 2018;839:76-94. doi:10.1017/jfm.2017.923
apa: Vasudevan, M., & Hof, B. (2018). The critical point of the transition to
turbulence in pipe flow. Journal of Fluid Mechanics. Cambridge University
Press. https://doi.org/10.1017/jfm.2017.923
chicago: Vasudevan, Mukund, and Björn Hof. “The Critical Point of the Transition
to Turbulence in Pipe Flow.” Journal of Fluid Mechanics. Cambridge University
Press, 2018. https://doi.org/10.1017/jfm.2017.923.
ieee: M. Vasudevan and B. Hof, “The critical point of the transition to turbulence
in pipe flow,” Journal of Fluid Mechanics, vol. 839. Cambridge University
Press, pp. 76–94, 2018.
ista: Vasudevan M, Hof B. 2018. The critical point of the transition to turbulence
in pipe flow. Journal of Fluid Mechanics. 839, 76–94.
mla: Vasudevan, Mukund, and Björn Hof. “The Critical Point of the Transition to
Turbulence in Pipe Flow.” Journal of Fluid Mechanics, vol. 839, Cambridge
University Press, 2018, pp. 76–94, doi:10.1017/jfm.2017.923.
short: M. Vasudevan, B. Hof, Journal of Fluid Mechanics 839 (2018) 76–94.
date_created: 2019-02-14T12:50:50Z
date_published: 2018-03-25T00:00:00Z
date_updated: 2025-04-14T13:36:56Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.923
ec_funded: 1
external_id:
arxiv:
- '1709.06372'
isi:
- '000437858300003'
intvolume: ' 839'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1709.06372
month: '03'
oa: 1
oa_version: Preprint
page: 76-94
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
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: The critical point of the transition to turbulence in pipe flow
type: journal_article
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 839
year: '2018'
...
---
_id: '1087'
abstract:
- lang: eng
text: Using extensive direct numerical simulations, the dynamics of laminar-turbulent
fronts in pipe flow is investigated for Reynolds numbers between and 5500. We
here investigate the physical distinction between the fronts of weak and strong
slugs both by analysing the turbulent kinetic energy budget and by comparing the
downstream front motion to the advection speed of bulk turbulent structures. Our
study shows that weak downstream fronts travel slower than turbulent structures
in the bulk and correspond to decaying turbulence at the front. At the downstream
front speed becomes faster than the advection speed, marking the onset of strong
fronts. In contrast to weak fronts, turbulent eddies are generated at strong fronts
by feeding on the downstream laminar flow. Our study also suggests that temporal
fluctuations of production and dissipation at the downstream laminar-turbulent
front drive the dynamical switches between the two types of front observed up
to.
acknowledged_ssus:
- _id: ScienComp
article_processing_charge: No
arxiv: 1
author:
- first_name: Baofang
full_name: Song, Baofang
last_name: Song
- 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
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
citation:
ama: Song B, Barkley D, Hof B, Avila M. Speed and structure of turbulent fronts
in pipe flow. Journal of Fluid Mechanics. 2017;813:1045-1059. doi:10.1017/jfm.2017.14
apa: Song, B., Barkley, D., Hof, B., & Avila, M. (2017). Speed and structure
of turbulent fronts in pipe flow. Journal of Fluid Mechanics. Cambridge
University Press. https://doi.org/10.1017/jfm.2017.14
chicago: Song, Baofang, Dwight Barkley, Björn Hof, and Marc Avila. “Speed and Structure
of Turbulent Fronts in Pipe Flow.” Journal of Fluid Mechanics. Cambridge
University Press, 2017. https://doi.org/10.1017/jfm.2017.14.
ieee: B. Song, D. Barkley, B. Hof, and M. Avila, “Speed and structure of turbulent
fronts in pipe flow,” Journal of Fluid Mechanics, vol. 813. Cambridge University
Press, pp. 1045–1059, 2017.
ista: Song B, Barkley D, Hof B, Avila M. 2017. Speed and structure of turbulent
fronts in pipe flow. Journal of Fluid Mechanics. 813, 1045–1059.
mla: Song, Baofang, et al. “Speed and Structure of Turbulent Fronts in Pipe Flow.”
Journal of Fluid Mechanics, vol. 813, Cambridge University Press, 2017,
pp. 1045–59, doi:10.1017/jfm.2017.14.
short: B. Song, D. Barkley, B. Hof, M. Avila, Journal of Fluid Mechanics 813 (2017)
1045–1059.
date_created: 2018-12-11T11:50:04Z
date_published: 2017-02-25T00:00:00Z
date_updated: 2025-06-04T08:35:11Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.14
ec_funded: 1
external_id:
arxiv:
- '1603.04077'
isi:
- '000394376400044'
intvolume: ' 813'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1603.04077
month: '02'
oa: 1
oa_version: Submitted Version
page: 1045 - 1059
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
publication: Journal of Fluid Mechanics
publication_identifier:
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
publist_id: '6290'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Speed and structure of turbulent fronts in pipe flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 813
year: '2017'
...
---
_id: '1021'
abstract:
- lang: eng
text: Most flows in nature and engineering are turbulent because of their large
velocities and spatial scales. Laboratory experiments on rotating quasi-Keplerian
flows, for which the angular velocity decreases radially but the angular momentum
increases, are however laminar at Reynolds numbers exceeding one million. This
is in apparent contradiction to direct numerical simulations showing that in these
experiments turbulence transition is triggered by the axial boundaries. We here
show numerically that as the Reynolds number increases, turbulence becomes progressively
confined to the boundary layers and the flow in the bulk fully relaminarizes.
Our findings support that turbulence is unlikely to occur in isothermal constant-density
quasi-Keplerian flows.
article_processing_charge: No
arxiv: 1
author:
- first_name: Jose M
full_name: Lopez Alonso, Jose M
id: 40770848-F248-11E8-B48F-1D18A9856A87
last_name: Lopez Alonso
orcid: 0000-0002-0384-2022
- first_name: Marc
full_name: Avila, Marc
last_name: Avila
citation:
ama: Lopez Alonso JM, Avila M. Boundary layer turbulence in experiments on quasi
Keplerian flows. Journal of Fluid Mechanics. 2017;817:21-34. doi:10.1017/jfm.2017.109
apa: Lopez Alonso, J. M., & Avila, M. (2017). Boundary layer turbulence in experiments
on quasi Keplerian flows. Journal of Fluid Mechanics. Cambridge University
Press. https://doi.org/10.1017/jfm.2017.109
chicago: Lopez Alonso, Jose M, and Marc Avila. “Boundary Layer Turbulence in Experiments
on Quasi Keplerian Flows.” Journal of Fluid Mechanics. Cambridge University
Press, 2017. https://doi.org/10.1017/jfm.2017.109.
ieee: J. M. Lopez Alonso and M. Avila, “Boundary layer turbulence in experiments
on quasi Keplerian flows,” Journal of Fluid Mechanics, vol. 817. Cambridge
University Press, pp. 21–34, 2017.
ista: Lopez Alonso JM, Avila M. 2017. Boundary layer turbulence in experiments on
quasi Keplerian flows. Journal of Fluid Mechanics. 817, 21–34.
mla: Lopez Alonso, Jose M., and Marc Avila. “Boundary Layer Turbulence in Experiments
on Quasi Keplerian Flows.” Journal of Fluid Mechanics, vol. 817, Cambridge
University Press, 2017, pp. 21–34, doi:10.1017/jfm.2017.109.
short: J.M. Lopez Alonso, M. Avila, Journal of Fluid Mechanics 817 (2017) 21–34.
date_created: 2018-12-11T11:49:44Z
date_published: 2017-04-25T00:00:00Z
date_updated: 2025-06-04T08:10:13Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.109
external_id:
arxiv:
- '1608.05527'
isi:
- '000398179100006'
intvolume: ' 817'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1608.05527
month: '04'
oa: 1
oa_version: Submitted Version
page: 21 - 34
project:
- _id: 255008E4-B435-11E9-9278-68D0E5697425
grant_number: RGP0065/2012
name: Information processing and computation in fish groups
publication: Journal of Fluid Mechanics
publication_identifier:
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
publist_id: '6371'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Boundary layer turbulence in experiments on quasi Keplerian flows
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 817
year: '2017'
...
---
_id: '792'
abstract:
- lang: eng
text: The chaotic dynamics of low-dimensional systems, such as Lorenz or Rössler
flows, is guided by the infinity of periodic orbits embedded in their strange
attractors. Whether this is also the case for the infinite-dimensional dynamics
of Navier–Stokes equations has long been speculated, and is a topic of ongoing
study. Periodic and relative periodic solutions have been shown to be involved
in transitions to turbulence. Their relevance to turbulent dynamics – specifically,
whether periodic orbits play the same role in high-dimensional nonlinear systems
like the Navier–Stokes equations as they do in lower-dimensional systems – is
the focus of the present investigation. We perform here a detailed study of pipe
flow relative periodic orbits with energies and mean dissipations close to turbulent
values. We outline several approaches to reduction of the translational symmetry
of the system. We study pipe flow in a minimal computational cell at Re=2500,
and report a library of invariant solutions found with the aid of the method of
slices. Detailed study of the unstable manifolds of a sample of these solutions
is consistent with the picture that relative periodic orbits are embedded in the
chaotic saddle and that they guide the turbulent dynamics.
article_processing_charge: No
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: Kimberly
full_name: Short, Kimberly
last_name: Short
- first_name: Mohammad
full_name: Farazmand, Mohammad
last_name: Farazmand
- first_name: Ashley
full_name: Willis, Ashley
last_name: Willis
- first_name: Predrag
full_name: Cvitanović, Predrag
last_name: Cvitanović
citation:
ama: Budanur NB, Short K, Farazmand M, Willis A, Cvitanović P. Relative periodic
orbits form the backbone of turbulent pipe flow. Journal of Fluid Mechanics.
2017;833:274-301. doi:10.1017/jfm.2017.699
apa: Budanur, N. B., Short, K., Farazmand, M., Willis, A., & Cvitanović, P.
(2017). Relative periodic orbits form the backbone of turbulent pipe flow. Journal
of Fluid Mechanics. Cambridge University Press. https://doi.org/10.1017/jfm.2017.699
chicago: Budanur, Nazmi B, Kimberly Short, Mohammad Farazmand, Ashley Willis, and
Predrag Cvitanović. “Relative Periodic Orbits Form the Backbone of Turbulent Pipe
Flow.” Journal of Fluid Mechanics. Cambridge University Press, 2017. https://doi.org/10.1017/jfm.2017.699.
ieee: N. B. Budanur, K. Short, M. Farazmand, A. Willis, and P. Cvitanović, “Relative
periodic orbits form the backbone of turbulent pipe flow,” Journal of Fluid
Mechanics, vol. 833. Cambridge University Press, pp. 274–301, 2017.
ista: Budanur NB, Short K, Farazmand M, Willis A, Cvitanović P. 2017. Relative periodic
orbits form the backbone of turbulent pipe flow. Journal of Fluid Mechanics. 833,
274–301.
mla: Budanur, Nazmi B., et al. “Relative Periodic Orbits Form the Backbone of Turbulent
Pipe Flow.” Journal of Fluid Mechanics, vol. 833, Cambridge University
Press, 2017, pp. 274–301, doi:10.1017/jfm.2017.699.
short: N.B. Budanur, K. Short, M. Farazmand, A. Willis, P. Cvitanović, Journal of
Fluid Mechanics 833 (2017) 274–301.
date_created: 2018-12-11T11:48:32Z
date_published: 2017-12-25T00:00:00Z
date_updated: 2025-06-04T09:45:57Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.699
external_id:
arxiv:
- '1705.03720'
isi:
- '000414641700001'
intvolume: ' 833'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1705.03720
month: '12'
oa: 1
oa_version: Submitted Version
page: 274 - 301
project:
- _id: 25636330-B435-11E9-9278-68D0E5697425
grant_number: 11-NSF-1070
name: Genome-wide Analysis of Root Traits
publication: Journal of Fluid Mechanics
publication_identifier:
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
publist_id: '6862'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Relative periodic orbits form the backbone of turbulent pipe flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 833
year: '2017'
...
---
_id: '824'
abstract:
- lang: eng
text: 'In shear flows at transitional Reynolds numbers, localized patches of turbulence,
known as puffs, coexist with the laminar flow. Recently, Avila et al. (Phys. Rev.
Lett., vol. 110, 2013, 224502) discovered two spatially localized relative periodic
solutions for pipe flow, which appeared in a saddle-node bifurcation at low Reynolds
number. Combining slicing methods for continuous symmetry reduction with Poincaré
sections for the first time in a shear flow setting, we compute and visualize
the unstable manifold of the lower-branch solution and show that it extends towards
the neighbourhood of the upper-branch solution. Surprisingly, this connection
even persists far above the bifurcation point and appears to mediate the first
stage of the puff generation: amplification of streamwise localized fluctuations.
When the state-space trajectories on the unstable manifold reach the vicinity
of the upper branch, corresponding fluctuations expand in space and eventually
take the usual shape of a puff.'
article_number: R1
article_processing_charge: No
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: 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. Heteroclinic path to spatially localized chaos in pipe flow.
Journal of Fluid Mechanics. 2017;827. doi:10.1017/jfm.2017.516
apa: Budanur, N. B., & Hof, B. (2017). Heteroclinic path to spatially localized
chaos in pipe flow. Journal of Fluid Mechanics. Cambridge University Press.
https://doi.org/10.1017/jfm.2017.516
chicago: Budanur, Nazmi B, and Björn Hof. “Heteroclinic Path to Spatially Localized
Chaos in Pipe Flow.” Journal of Fluid Mechanics. Cambridge University Press,
2017. https://doi.org/10.1017/jfm.2017.516.
ieee: N. B. Budanur and B. Hof, “Heteroclinic path to spatially localized chaos
in pipe flow,” Journal of Fluid Mechanics, vol. 827. Cambridge University
Press, 2017.
ista: Budanur NB, Hof B. 2017. Heteroclinic path to spatially localized chaos in
pipe flow. Journal of Fluid Mechanics. 827, R1.
mla: Budanur, Nazmi B., and Björn Hof. “Heteroclinic Path to Spatially Localized
Chaos in Pipe Flow.” Journal of Fluid Mechanics, vol. 827, R1, Cambridge
University Press, 2017, doi:10.1017/jfm.2017.516.
short: N.B. Budanur, B. Hof, Journal of Fluid Mechanics 827 (2017).
date_created: 2018-12-11T11:48:42Z
date_published: 2017-08-18T00:00:00Z
date_updated: 2025-06-04T09:49:26Z
day: '18'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.516
external_id:
arxiv:
- '1703.10484'
isi:
- '000408326300001'
intvolume: ' 827'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1703.10484
month: '08'
oa: 1
oa_version: Submitted Version
publication: Journal of Fluid Mechanics
publication_identifier:
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
publist_id: '6824'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Heteroclinic path to spatially localized chaos in pipe flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 827
year: '2017'
...
---
_id: '745'
abstract:
- lang: eng
text: 'Fluid flows in nature and applications are frequently subject to periodic
velocity modulations. Surprisingly, even for the generic case of flow through
a straight pipe, there is little consensus regarding the influence of pulsation
on the transition threshold to turbulence: while most studies predict a monotonically
increasing threshold with pulsation frequency (i.e. Womersley number, ), others
observe a decreasing threshold for identical parameters and only observe an increasing
threshold at low . In the present study we apply recent advances in the understanding
of transition in steady shear flows to pulsating pipe flow. For moderate pulsation
amplitudes we find that the first instability encountered is subcritical (i.e.
requiring finite amplitude disturbances) and gives rise to localized patches of
turbulence (''puffs'') analogous to steady pipe flow. By monitoring the impact
of pulsation on the lifetime of turbulence we map the onset of turbulence in parameter
space. Transition in pulsatile flow can be separated into three regimes. At small
Womersley numbers the dynamics is dominated by the decay turbulence suffers during
the slower part of the cycle and hence transition is delayed significantly. As
shown in this regime thresholds closely agree with estimates based on a quasi-steady
flow assumption only taking puff decay rates into account. The transition point
predicted in the zero limit equals to the critical point for steady pipe flow
offset by the oscillation Reynolds number (i.e. the dimensionless oscillation
amplitude). In the high frequency limit on the other hand, puff lifetimes are
identical to those in steady pipe flow and hence the transition threshold appears
to be unaffected by flow pulsation. In the intermediate frequency regime the transition
threshold sharply drops (with increasing ) from the decay dominated (quasi-steady)
threshold to the steady pipe flow level.'
article_processing_charge: No
arxiv: 1
author:
- first_name: Duo
full_name: Xu, Duo
id: 3454D55E-F248-11E8-B48F-1D18A9856A87
last_name: Xu
- first_name: Sascha
full_name: Warnecke, Sascha
last_name: Warnecke
- first_name: Baofang
full_name: Song, Baofang
last_name: Song
- first_name: Xingyu
full_name: Ma, Xingyu
id: 34BADBA6-F248-11E8-B48F-1D18A9856A87
last_name: Ma
orcid: 0000-0002-0179-9737
- 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, Warnecke S, Song B, Ma X, Hof B. Transition to turbulence in pulsating
pipe flow. Journal of Fluid Mechanics. 2017;831:418-432. doi:10.1017/jfm.2017.620
apa: Xu, D., Warnecke, S., Song, B., Ma, X., & Hof, B. (2017). Transition to
turbulence in pulsating pipe flow. Journal of Fluid Mechanics. Cambridge
University Press. https://doi.org/10.1017/jfm.2017.620
chicago: Xu, Duo, Sascha Warnecke, Baofang Song, Xingyu Ma, and Björn Hof. “Transition
to Turbulence in Pulsating Pipe Flow.” Journal of Fluid Mechanics. Cambridge
University Press, 2017. https://doi.org/10.1017/jfm.2017.620.
ieee: D. Xu, S. Warnecke, B. Song, X. Ma, and B. Hof, “Transition to turbulence
in pulsating pipe flow,” Journal of Fluid Mechanics, vol. 831. Cambridge
University Press, pp. 418–432, 2017.
ista: Xu D, Warnecke S, Song B, Ma X, Hof B. 2017. Transition to turbulence in pulsating
pipe flow. Journal of Fluid Mechanics. 831, 418–432.
mla: Xu, Duo, et al. “Transition to Turbulence in Pulsating Pipe Flow.” Journal
of Fluid Mechanics, vol. 831, Cambridge University Press, 2017, pp. 418–32,
doi:10.1017/jfm.2017.620.
short: D. Xu, S. Warnecke, B. Song, X. Ma, B. Hof, Journal of Fluid Mechanics 831
(2017) 418–432.
corr_author: '1'
date_created: 2018-12-11T11:48:17Z
date_published: 2017-11-25T00:00:00Z
date_updated: 2025-06-04T09:44:06Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.620
ec_funded: 1
external_id:
arxiv:
- '1709.03738'
isi:
- '000412934800005'
intvolume: ' 831'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/abs/1709.03738
month: '11'
oa: 1
oa_version: Submitted Version
page: 418 - 432
project:
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '306589'
name: Decoding the complexity of turbulence at its origin
publication: Journal of Fluid Mechanics
publication_identifier:
issn:
- 0022-1120
publication_status: published
publisher: Cambridge University Press
publist_id: '6922'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Transition to turbulence in pulsating pipe flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 831
year: '2017'
...
---
_id: '9149'
abstract:
- lang: eng
text: "The interaction of tidal currents with sea-floor topography results in the
radiation of internal gravity waves into the ocean interior. These waves are called
internal tides and their dissipation due to nonlinear wave breaking and concomitant
three-dimensional turbulence could play an important role in the mixing of the
abyssal ocean, and hence in controlling the large-scale ocean circulation.\r\nAs
part of on-going work aimed at providing a theory for the vertical distribution
of wave breaking over sea-floor topography, in this paper we investigate the instability
of internal tides in a very simple linear model that helps us to relate the formation
of unstable regions to simple features in the sea-floor topography. For two-dimensional
tides over one-dimensional topography we find that the formation of overturning
instabilities is closely linked to the singularities in the topography shape and
that it is possible to have stable waves at the sea floor and unstable waves in
the ocean interior above.\r\nFor three-dimensional tides over two-dimensional
topography there is in addition an effect of geometric focusing of wave energy
into localized regions of high wave amplitude, and we investigate this focusing
effect in simple examples. Overall, we find that the distribution of unstable
wave breaking regions can be highly non-uniform even for very simple idealized
topography shapes."
article_processing_charge: No
article_type: original
author:
- first_name: Oliver
full_name: Bühler, Oliver
last_name: Bühler
- first_name: Caroline J
full_name: Muller, Caroline J
id: f978ccb0-3f7f-11eb-b193-b0e2bd13182b
last_name: Muller
orcid: 0000-0001-5836-5350
citation:
ama: Bühler O, Muller CJ. Instability and focusing of internal tides in the deep
ocean. Journal of Fluid Mechanics. 2007;588:1-28. doi:10.1017/s0022112007007410
apa: Bühler, O., & Muller, C. J. (2007). Instability and focusing of internal
tides in the deep ocean. Journal of Fluid Mechanics. Cambridge University
Press. https://doi.org/10.1017/s0022112007007410
chicago: Bühler, Oliver, and Caroline J Muller. “Instability and Focusing of Internal
Tides in the Deep Ocean.” Journal of Fluid Mechanics. Cambridge University
Press, 2007. https://doi.org/10.1017/s0022112007007410.
ieee: O. Bühler and C. J. Muller, “Instability and focusing of internal tides in
the deep ocean,” Journal of Fluid Mechanics, vol. 588. Cambridge University
Press, pp. 1–28, 2007.
ista: Bühler O, Muller CJ. 2007. Instability and focusing of internal tides in the
deep ocean. Journal of Fluid Mechanics. 588, 1–28.
mla: Bühler, Oliver, and Caroline J. Muller. “Instability and Focusing of Internal
Tides in the Deep Ocean.” Journal of Fluid Mechanics, vol. 588, Cambridge
University Press, 2007, pp. 1–28, doi:10.1017/s0022112007007410.
short: O. Bühler, C.J. Muller, Journal of Fluid Mechanics 588 (2007) 1–28.
date_created: 2021-02-15T14:41:45Z
date_published: 2007-10-10T00:00:00Z
date_updated: 2022-01-24T13:43:36Z
day: '10'
doi: 10.1017/s0022112007007410
extern: '1'
intvolume: ' 588'
keyword:
- mechanical engineering
- mechanics of materials
- condensed matter physics
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://doi.org/10.1017/S0022112007007410
month: '10'
oa: 1
oa_version: None
page: 1-28
publication: Journal of Fluid Mechanics
publication_identifier:
issn:
- 0022-1120
- 1469-7645
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
status: public
title: Instability and focusing of internal tides in the deep ocean
type: journal_article
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
volume: 588
year: '2007'
...