---
_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. <i>Journal of Fluid Mechanics</i>.
    2021;915. doi:<a href="https://doi.org/10.1017/jfm.2021.89">10.1017/jfm.2021.89</a>
  apa: Liu, T., Semin, B., Klotz, L., Godoy-Diana, R., Wesfreid, J. E., &#38; Mullin,
    T. (2021). Decay of streaks and rolls in plane Couette-Poiseuille flow. <i>Journal
    of Fluid Mechanics</i>. Cambridge University Press. <a href="https://doi.org/10.1017/jfm.2021.89">https://doi.org/10.1017/jfm.2021.89</a>
  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.” <i>Journal
    of Fluid Mechanics</i>. Cambridge University Press, 2021. <a href="https://doi.org/10.1017/jfm.2021.89">https://doi.org/10.1017/jfm.2021.89</a>.
  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,” <i>Journal of Fluid
    Mechanics</i>, 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.”
    <i>Journal of Fluid Mechanics</i>, vol. 915, A65, Cambridge University Press,
    2021, doi:<a href="https://doi.org/10.1017/jfm.2021.89">10.1017/jfm.2021.89</a>.
  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'
...