---
_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
- first_name: Shuisheng
full_name: He, Shuisheng
last_name: He
- first_name: Ashley P.
full_name: Willis, Ashley P.
last_name: Willis
citation:
ama: Marensi E, He S, Willis AP. Suppression of turbulence and travelling waves
in a vertical heated pipe. Journal of Fluid Mechanics. 2021;919. doi:10.1017/jfm.2021.371
apa: Marensi, E., He, S., & Willis, A. P. (2021). Suppression of turbulence
and travelling waves in a vertical heated pipe. Journal of Fluid Mechanics.
Cambridge University Press. https://doi.org/10.1017/jfm.2021.371
chicago: Marensi, Elena, Shuisheng He, and Ashley P. Willis. “Suppression of Turbulence
and Travelling Waves in a Vertical Heated Pipe.” Journal of Fluid Mechanics.
Cambridge University Press, 2021. https://doi.org/10.1017/jfm.2021.371.
ieee: E. Marensi, S. He, and A. P. Willis, “Suppression of turbulence and travelling
waves in a vertical heated pipe,” Journal of Fluid Mechanics, vol. 919.
Cambridge University Press, 2021.
ista: Marensi E, He S, Willis AP. 2021. Suppression of turbulence and travelling
waves in a vertical heated pipe. Journal of Fluid Mechanics. 919, A17.
mla: Marensi, Elena, et al. “Suppression of Turbulence and Travelling Waves in a
Vertical Heated Pipe.” Journal of Fluid Mechanics, vol. 919, A17, Cambridge
University Press, 2021, doi:10.1017/jfm.2021.371.
short: E. Marensi, S. He, A.P. Willis, Journal of Fluid Mechanics 919 (2021).
date_created: 2021-06-06T22:01:30Z
date_published: 2021-07-25T00:00:00Z
date_updated: 2023-08-08T13:58:41Z
day: '25'
ddc:
- '530'
department:
- _id: BjHo
doi: 10.1017/jfm.2021.371
external_id:
arxiv:
- '2008.13486'
isi:
- '000653785000001'
file:
- access_level: open_access
checksum: 867ad077e45c181c2c5ec1311ba27c41
content_type: application/pdf
creator: kschuh
date_created: 2021-08-03T09:53:28Z
date_updated: 2021-08-03T09:53:28Z
file_id: '9766'
file_name: 2021_JournalFluidMechanics_Marensi.pdf
file_size: 4087358
relation: main_file
success: 1
file_date_updated: 2021-08-03T09:53:28Z
has_accepted_license: '1'
intvolume: ' 919'
isi: 1
language:
- iso: eng
month: '07'
oa: 1
oa_version: Published Version
publication: Journal of Fluid Mechanics
publication_identifier:
eissn:
- '14697645'
issn:
- '00221120'
publication_status: published
publisher: Cambridge University Press
quality_controlled: '1'
scopus_import: '1'
status: public
title: Suppression of turbulence and travelling waves in a vertical heated pipe
tmp:
image: /images/cc_by.png
legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
short: CC BY (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 919
year: '2021'
...
---
_id: '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: '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: 2024-03-25T23:30:20Z
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:
- '14697645'
issn:
- '00221120'
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: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 867
year: '2019'
...
---
_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
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: 2023-09-20T11:47:22Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.14
ec_funded: 1
external_id:
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:
- '00221120'
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 813
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
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: 2023-09-27T12:17:35Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.699
external_id:
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: ROOTS Genome-wide Analysis of Root Traits
publication: Journal of Fluid Mechanics
publication_identifier:
issn:
- '00221120'
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
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
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: 2023-09-26T16:17:43Z
day: '18'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.516
external_id:
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:
- '00221120'
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
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
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.
date_created: 2018-12-11T11:48:17Z
date_published: 2017-11-25T00:00:00Z
date_updated: 2023-09-27T12:28:12Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.620
ec_funded: 1
external_id:
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:
- '00221120'
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 831
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
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: 2023-09-22T09:39:46Z
day: '25'
department:
- _id: BjHo
doi: 10.1017/jfm.2017.109
external_id:
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:
- '00221120'
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 817
year: '2017'
...