---
_id: '14341'
abstract:
- lang: eng
  text: Flows through pipes and channels are, in practice, almost always turbulent,
    and the multiscale eddying motion is responsible for a major part of the encountered
    friction losses and pumping costs1. Conversely, for pulsatile flows, in particular
    for aortic blood flow, turbulence levels remain low despite relatively large peak
    velocities. For aortic blood flow, high turbulence levels are intolerable as they
    would damage the shear-sensitive endothelial cell layer2,3,4,5. Here we show that
    turbulence in ordinary pipe flow is diminished if the flow is driven in a pulsatile
    mode that incorporates all the key features of the cardiac waveform. At Reynolds
    numbers comparable to those of aortic blood flow, turbulence is largely inhibited,
    whereas at much higher speeds, the turbulent drag is reduced by more than 25%.
    This specific operation mode is more efficient when compared with steady driving,
    which is the present situation for virtually all fluid transport processes ranging
    from heating circuits to water, gas and oil pipelines.
acknowledged_ssus:
- _id: M-Shop
- _id: ScienComp
acknowledgement: We acknowledge the assistance of the Miba machine shop and the team
  of the ISTA-HPC cluster. We thank M. Quadrio for the discussions. The work was supported
  by the Simons Foundation (grant no. 662960) and by the Austrian Science Fund (grant
  no. I4188-N30), within Deutsche Forschungsgemeinschaft research unit FOR 2688.
article_processing_charge: No
article_type: original
author:
- first_name: Davide
  full_name: Scarselli, Davide
  id: 40315C30-F248-11E8-B48F-1D18A9856A87
  last_name: Scarselli
  orcid: 0000-0001-5227-4271
- first_name: Jose M
  full_name: Lopez Alonso, Jose M
  id: 40770848-F248-11E8-B48F-1D18A9856A87
  last_name: Lopez Alonso
  orcid: 0000-0002-0384-2022
- first_name: Atul
  full_name: Varshney, Atul
  id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
  last_name: Varshney
  orcid: 0000-0002-3072-5999
- first_name: Björn
  full_name: Hof, Björn
  id: 3A374330-F248-11E8-B48F-1D18A9856A87
  last_name: Hof
  orcid: 0000-0003-2057-2754
citation:
  ama: Scarselli D, Lopez Alonso JM, Varshney A, Hof B. Turbulence suppression by
    cardiac-cycle-inspired driving of pipe flow. <i>Nature</i>. 2023;621(7977):71-74.
    doi:<a href="https://doi.org/10.1038/s41586-023-06399-5">10.1038/s41586-023-06399-5</a>
  apa: Scarselli, D., Lopez Alonso, J. M., Varshney, A., &#38; Hof, B. (2023). Turbulence
    suppression by cardiac-cycle-inspired driving of pipe flow. <i>Nature</i>. Springer
    Nature. <a href="https://doi.org/10.1038/s41586-023-06399-5">https://doi.org/10.1038/s41586-023-06399-5</a>
  chicago: Scarselli, Davide, Jose M Lopez Alonso, Atul Varshney, and Björn Hof. “Turbulence
    Suppression by Cardiac-Cycle-Inspired Driving of Pipe Flow.” <i>Nature</i>. Springer
    Nature, 2023. <a href="https://doi.org/10.1038/s41586-023-06399-5">https://doi.org/10.1038/s41586-023-06399-5</a>.
  ieee: D. Scarselli, J. M. Lopez Alonso, A. Varshney, and B. Hof, “Turbulence suppression
    by cardiac-cycle-inspired driving of pipe flow,” <i>Nature</i>, vol. 621, no.
    7977. Springer Nature, pp. 71–74, 2023.
  ista: Scarselli D, Lopez Alonso JM, Varshney A, Hof B. 2023. Turbulence suppression
    by cardiac-cycle-inspired driving of pipe flow. Nature. 621(7977), 71–74.
  mla: Scarselli, Davide, et al. “Turbulence Suppression by Cardiac-Cycle-Inspired
    Driving of Pipe Flow.” <i>Nature</i>, vol. 621, no. 7977, Springer Nature, 2023,
    pp. 71–74, doi:<a href="https://doi.org/10.1038/s41586-023-06399-5">10.1038/s41586-023-06399-5</a>.
  short: D. Scarselli, J.M. Lopez Alonso, A. Varshney, B. Hof, Nature 621 (2023) 71–74.
date_created: 2023-09-17T22:01:09Z
date_published: 2023-09-07T00:00:00Z
date_updated: 2023-09-20T12:10:22Z
day: '07'
department:
- _id: BjHo
doi: 10.1038/s41586-023-06399-5
external_id:
  pmid:
  - '37673988'
intvolume: '       621'
issue: '7977'
language:
- iso: eng
month: '09'
oa_version: None
page: 71-74
pmid: 1
project:
- _id: 238598C6-32DE-11EA-91FC-C7463DDC885E
  grant_number: '662960'
  name: 'Revisiting the Turbulence Problem Using Statistical Mechanics: Experimental
    Studies on Transitional and Turbulent Flows'
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
  call_identifier: FWF
  grant_number: I04188
  name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
publication: Nature
publication_identifier:
  eissn:
  - 1476-4687
  issn:
  - 0028-0836
publication_status: published
publisher: Springer Nature
quality_controlled: '1'
related_material:
  link:
  - description: News on ISTA website
    relation: press_release
    url: https://www.ista.ac.at/en/news/pumping-like-the-heart/
scopus_import: '1'
status: public
title: Turbulence suppression by cardiac-cycle-inspired driving of pipe flow
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 621
year: '2023'
...
---
_id: '10299'
abstract:
- lang: eng
  text: Turbulence generally arises in shear flows if velocities and hence, inertial
    forces are sufficiently large. In striking contrast, viscoelastic fluids can exhibit
    disordered motion even at vanishing inertia. Intermediate between these cases,
    a state of chaotic motion, “elastoinertial turbulence” (EIT), has been observed
    in a narrow Reynolds number interval. We here determine the origin of EIT in experiments
    and show that characteristic EIT structures can be detected across an unexpectedly
    wide range of parameters. Close to onset, a pattern of chevron-shaped streaks
    emerges in qualitative agreement with linear and weakly nonlinear theory. However,
    in experiments, the dynamics remain weakly chaotic, and the instability can be
    traced to far lower Reynolds numbers than permitted by theory. For increasing
    inertia, the flow undergoes a transformation to a wall mode composed of inclined
    near-wall streaks and shear layers. This mode persists to what is known as the
    “maximum drag reduction limit,” and overall EIT is found to dominate viscoelastic
    flows across more than three orders of magnitude in Reynolds number.
acknowledgement: We thank Y. Dubief, R. Kerswell, E. Marensi, V. Shankar, V. Steinberg,
  and V. Terrapon for discussions and helpful comments. A.V. and B.H. acknowledge
  funding from the Austrian Science Fund, grant I4188-N30, within the Deutsche Forschungsgemeinschaft
  research unit FOR 2688.
article_number: e2102350118
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: George H
  full_name: Choueiri, George H
  id: 448BD5BC-F248-11E8-B48F-1D18A9856A87
  last_name: Choueiri
- first_name: Jose M
  full_name: Lopez Alonso, Jose M
  id: 40770848-F248-11E8-B48F-1D18A9856A87
  last_name: Lopez Alonso
  orcid: 0000-0002-0384-2022
- first_name: Atul
  full_name: Varshney, Atul
  id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
  last_name: Varshney
  orcid: 0000-0002-3072-5999
- first_name: Sarath
  full_name: Sankar, Sarath
  last_name: Sankar
- first_name: Björn
  full_name: Hof, Björn
  id: 3A374330-F248-11E8-B48F-1D18A9856A87
  last_name: Hof
  orcid: 0000-0003-2057-2754
citation:
  ama: Choueiri GH, Lopez Alonso JM, Varshney A, Sankar S, Hof B. Experimental observation
    of the origin and structure of elastoinertial turbulence. <i>Proceedings of the
    National Academy of Sciences</i>. 2021;118(45). doi:<a href="https://doi.org/10.1073/pnas.2102350118">10.1073/pnas.2102350118</a>
  apa: Choueiri, G. H., Lopez Alonso, J. M., Varshney, A., Sankar, S., &#38; Hof,
    B. (2021). Experimental observation of the origin and structure of elastoinertial
    turbulence. <i>Proceedings of the National Academy of Sciences</i>. National Academy
    of Sciences. <a href="https://doi.org/10.1073/pnas.2102350118">https://doi.org/10.1073/pnas.2102350118</a>
  chicago: Choueiri, George H, Jose M Lopez Alonso, Atul Varshney, Sarath Sankar,
    and Björn Hof. “Experimental Observation of the Origin and Structure of Elastoinertial
    Turbulence.” <i>Proceedings of the National Academy of Sciences</i>. National
    Academy of Sciences, 2021. <a href="https://doi.org/10.1073/pnas.2102350118">https://doi.org/10.1073/pnas.2102350118</a>.
  ieee: G. H. Choueiri, J. M. Lopez Alonso, A. Varshney, S. Sankar, and B. Hof, “Experimental
    observation of the origin and structure of elastoinertial turbulence,” <i>Proceedings
    of the National Academy of Sciences</i>, vol. 118, no. 45. National Academy of
    Sciences, 2021.
  ista: Choueiri GH, Lopez Alonso JM, Varshney A, Sankar S, Hof B. 2021. Experimental
    observation of the origin and structure of elastoinertial turbulence. Proceedings
    of the National Academy of Sciences. 118(45), e2102350118.
  mla: Choueiri, George H., et al. “Experimental Observation of the Origin and Structure
    of Elastoinertial Turbulence.” <i>Proceedings of the National Academy of Sciences</i>,
    vol. 118, no. 45, e2102350118, National Academy of Sciences, 2021, doi:<a href="https://doi.org/10.1073/pnas.2102350118">10.1073/pnas.2102350118</a>.
  short: G.H. Choueiri, J.M. Lopez Alonso, A. Varshney, S. Sankar, B. Hof, Proceedings
    of the National Academy of Sciences 118 (2021).
date_created: 2021-11-17T13:24:24Z
date_published: 2021-11-03T00:00:00Z
date_updated: 2023-08-14T11:50:10Z
day: '03'
department:
- _id: BjHo
doi: 10.1073/pnas.2102350118
external_id:
  arxiv:
  - '2103.00023'
  isi:
  - '000720926900019'
  pmid:
  - ' 34732570'
intvolume: '       118'
isi: 1
issue: '45'
keyword:
- multidisciplinary
- elastoinertial turbulence
- viscoelastic flows
- elastic instability
- drag reduction
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/2103.00023
month: '11'
oa: 1
oa_version: Preprint
pmid: 1
project:
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
  call_identifier: FWF
  grant_number: I04188
  name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
publication: Proceedings of the National Academy of Sciences
publication_identifier:
  eissn:
  - 1091-6490
  issn:
  - 0027-8424
publication_status: published
publisher: National Academy of Sciences
quality_controlled: '1'
scopus_import: '1'
status: public
title: Experimental observation of the origin and structure of elastoinertial turbulence
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 118
year: '2021'
...
---
_id: '7932'
abstract:
- lang: eng
  text: Pulsating flows through tubular geometries are laminar provided that velocities
    are moderate. This in particular is also believed to apply to cardiovascular flows
    where inertial forces are typically too low to sustain turbulence. On the other
    hand, flow instabilities and fluctuating shear stresses are held responsible for
    a variety of cardiovascular diseases. Here we report a nonlinear instability mechanism
    for pulsating pipe flow that gives rise to bursts of turbulence at low flow rates.
    Geometrical distortions of small, yet finite, amplitude are found to excite a
    state consisting of helical vortices during flow deceleration. The resulting flow
    pattern grows rapidly in magnitude, breaks down into turbulence, and eventually
    returns to laminar when the flow accelerates. This scenario causes shear stress
    fluctuations and flow reversal during each pulsation cycle. Such unsteady conditions
    can adversely affect blood vessels and have been shown to promote inflammation
    and dysfunction of the shear stress-sensitive endothelial cell layer.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Duo
  full_name: Xu, Duo
  id: 3454D55E-F248-11E8-B48F-1D18A9856A87
  last_name: Xu
- first_name: Atul
  full_name: Varshney, Atul
  id: 2A2006B2-F248-11E8-B48F-1D18A9856A87
  last_name: Varshney
  orcid: 0000-0002-3072-5999
- first_name: Xingyu
  full_name: Ma, Xingyu
  id: 34BADBA6-F248-11E8-B48F-1D18A9856A87
  last_name: Ma
  orcid: 0000-0002-0179-9737
- first_name: Baofang
  full_name: Song, Baofang
  last_name: Song
- first_name: Michael
  full_name: Riedl, Michael
  id: 3BE60946-F248-11E8-B48F-1D18A9856A87
  last_name: Riedl
  orcid: 0000-0003-4844-6311
- first_name: Marc
  full_name: Avila, Marc
  last_name: Avila
- first_name: Björn
  full_name: Hof, Björn
  id: 3A374330-F248-11E8-B48F-1D18A9856A87
  last_name: Hof
  orcid: 0000-0003-2057-2754
citation:
  ama: Xu D, Varshney A, Ma X, et al. Nonlinear hydrodynamic instability and turbulence
    in pulsatile flow. <i>Proceedings of the National Academy of Sciences of the United
    States of America</i>. 2020;117(21):11233-11239. doi:<a href="https://doi.org/10.1073/pnas.1913716117">10.1073/pnas.1913716117</a>
  apa: Xu, D., Varshney, A., Ma, X., Song, B., Riedl, M., Avila, M., &#38; Hof, B.
    (2020). Nonlinear hydrodynamic instability and turbulence in pulsatile flow. <i>Proceedings
    of the National Academy of Sciences of the United States of America</i>. National
    Academy of Sciences. <a href="https://doi.org/10.1073/pnas.1913716117">https://doi.org/10.1073/pnas.1913716117</a>
  chicago: Xu, Duo, Atul Varshney, Xingyu Ma, Baofang Song, Michael Riedl, Marc Avila,
    and Björn Hof. “Nonlinear Hydrodynamic Instability and Turbulence in Pulsatile
    Flow.” <i>Proceedings of the National Academy of Sciences of the United States
    of America</i>. National Academy of Sciences, 2020. <a href="https://doi.org/10.1073/pnas.1913716117">https://doi.org/10.1073/pnas.1913716117</a>.
  ieee: D. Xu <i>et al.</i>, “Nonlinear hydrodynamic instability and turbulence in
    pulsatile flow,” <i>Proceedings of the National Academy of Sciences of the United
    States of America</i>, vol. 117, no. 21. National Academy of Sciences, pp. 11233–11239,
    2020.
  ista: Xu D, Varshney A, Ma X, Song B, Riedl M, Avila M, Hof B. 2020. Nonlinear hydrodynamic
    instability and turbulence in pulsatile flow. Proceedings of the National Academy
    of Sciences of the United States of America. 117(21), 11233–11239.
  mla: Xu, Duo, et al. “Nonlinear Hydrodynamic Instability and Turbulence in Pulsatile
    Flow.” <i>Proceedings of the National Academy of Sciences of the United States
    of America</i>, vol. 117, no. 21, National Academy of Sciences, 2020, pp. 11233–39,
    doi:<a href="https://doi.org/10.1073/pnas.1913716117">10.1073/pnas.1913716117</a>.
  short: D. Xu, A. Varshney, X. Ma, B. Song, M. Riedl, M. Avila, B. Hof, Proceedings
    of the National Academy of Sciences of the United States of America 117 (2020)
    11233–11239.
date_created: 2020-06-07T22:00:51Z
date_published: 2020-05-26T00:00:00Z
date_updated: 2023-11-30T10:55:13Z
day: '26'
department:
- _id: BjHo
doi: 10.1073/pnas.1913716117
ec_funded: 1
external_id:
  arxiv:
  - '2005.11190'
  isi:
  - '000536797100014'
intvolume: '       117'
isi: 1
issue: '21'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/2005.11190
month: '05'
oa: 1
oa_version: Preprint
page: 11233-11239
project:
- _id: 238B8092-32DE-11EA-91FC-C7463DDC885E
  call_identifier: FWF
  grant_number: I04188
  name: Instabilities in pulsating pipe flow of Newtonian and complex fluids
- _id: 260C2330-B435-11E9-9278-68D0E5697425
  call_identifier: H2020
  grant_number: '754411'
  name: ISTplus - Postdoctoral Fellowships
publication: Proceedings of the National Academy of Sciences of the United States
  of America
publication_identifier:
  eissn:
  - '10916490'
  issn:
  - '00278424'
publication_status: published
publisher: National Academy of Sciences
quality_controlled: '1'
related_material:
  link:
  - description: News on IST Homepage
    relation: press_release
    url: https://ist.ac.at/en/news/blood-flows-more-turbulent-than-previously-expected/
  record:
  - id: '12726'
    relation: dissertation_contains
    status: public
  - id: '14530'
    relation: dissertation_contains
    status: public
scopus_import: '1'
status: public
title: Nonlinear hydrodynamic instability and turbulence in pulsatile flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 117
year: '2020'
...
