---
_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: '7364'
abstract:
- lang: eng
  text: We present nsCouette, a highly scalable software tool to solve the Navier–Stokes
    equations for incompressible fluid flow between differentially heated and independently
    rotating, concentric cylinders. It is based on a pseudospectral spatial discretization
    and dynamic time-stepping. It is implemented in modern Fortran with a hybrid MPI-OpenMP
    parallelization scheme and thus designed to compute turbulent flows at high Reynolds
    and Rayleigh numbers. An additional GPU implementation (C-CUDA) for intermediate
    problem sizes and a version for pipe flow (nsPipe) are also provided.
article_number: '100395'
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: Daniel
  full_name: Feldmann, Daniel
  last_name: Feldmann
- first_name: Markus
  full_name: Rampp, Markus
  last_name: Rampp
- first_name: Alberto
  full_name: Vela-Martín, Alberto
  last_name: Vela-Martín
- first_name: Liang
  full_name: Shi, Liang
  id: 374A3F1A-F248-11E8-B48F-1D18A9856A87
  last_name: Shi
- first_name: Marc
  full_name: Avila, Marc
  last_name: Avila
citation:
  ama: Lopez Alonso JM, Feldmann D, Rampp M, Vela-Martín A, Shi L, Avila M. nsCouette
    – A high-performance code for direct numerical simulations of turbulent Taylor–Couette
    flow. <i>SoftwareX</i>. 2020;11. doi:<a href="https://doi.org/10.1016/j.softx.2019.100395">10.1016/j.softx.2019.100395</a>
  apa: Lopez Alonso, J. M., Feldmann, D., Rampp, M., Vela-Martín, A., Shi, L., &#38;
    Avila, M. (2020). nsCouette – A high-performance code for direct numerical simulations
    of turbulent Taylor–Couette flow. <i>SoftwareX</i>. Elsevier. <a href="https://doi.org/10.1016/j.softx.2019.100395">https://doi.org/10.1016/j.softx.2019.100395</a>
  chicago: Lopez Alonso, Jose M, Daniel Feldmann, Markus Rampp, Alberto Vela-Martín,
    Liang Shi, and Marc Avila. “NsCouette – A High-Performance Code for Direct Numerical
    Simulations of Turbulent Taylor–Couette Flow.” <i>SoftwareX</i>. Elsevier, 2020.
    <a href="https://doi.org/10.1016/j.softx.2019.100395">https://doi.org/10.1016/j.softx.2019.100395</a>.
  ieee: J. M. Lopez Alonso, D. Feldmann, M. Rampp, A. Vela-Martín, L. Shi, and M.
    Avila, “nsCouette – A high-performance code for direct numerical simulations of
    turbulent Taylor–Couette flow,” <i>SoftwareX</i>, vol. 11. Elsevier, 2020.
  ista: Lopez Alonso JM, Feldmann D, Rampp M, Vela-Martín A, Shi L, Avila M. 2020.
    nsCouette – A high-performance code for direct numerical simulations of turbulent
    Taylor–Couette flow. SoftwareX. 11, 100395.
  mla: Lopez Alonso, Jose M., et al. “NsCouette – A High-Performance Code for Direct
    Numerical Simulations of Turbulent Taylor–Couette Flow.” <i>SoftwareX</i>, vol.
    11, 100395, Elsevier, 2020, doi:<a href="https://doi.org/10.1016/j.softx.2019.100395">10.1016/j.softx.2019.100395</a>.
  short: J.M. Lopez Alonso, D. Feldmann, M. Rampp, A. Vela-Martín, L. Shi, M. Avila,
    SoftwareX 11 (2020).
date_created: 2020-01-26T23:00:35Z
date_published: 2020-01-17T00:00:00Z
date_updated: 2023-08-17T14:29:59Z
day: '17'
ddc:
- '000'
department:
- _id: BjHo
doi: 10.1016/j.softx.2019.100395
external_id:
  arxiv:
  - '1908.00587'
  isi:
  - '000552271200011'
file:
- access_level: open_access
  checksum: 2af1a1a3cc33557b345145276f221668
  content_type: application/pdf
  creator: dernst
  date_created: 2020-01-27T07:32:46Z
  date_updated: 2020-07-14T12:47:56Z
  file_id: '7365'
  file_name: 2020_SoftwareX_Lopez.pdf
  file_size: 679707
  relation: main_file
file_date_updated: 2020-07-14T12:47:56Z
has_accepted_license: '1'
intvolume: '        11'
isi: 1
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-nd/4.0/
month: '01'
oa: 1
oa_version: Published Version
publication: SoftwareX
publication_identifier:
  eissn:
  - '23527110'
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: nsCouette – A high-performance code for direct numerical simulations of turbulent
  Taylor–Couette flow
tmp:
  image: /images/cc_by_nc_nd.png
  legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
  name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
    (CC BY-NC-ND 4.0)
  short: CC BY-NC-ND (4.0)
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 11
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. <i>Journal of Fluid
    Mechanics</i>. 2019;874:699-719. doi:<a href="https://doi.org/10.1017/jfm.2019.486">10.1017/jfm.2019.486</a>
  apa: Lopez Alonso, J. M., Choueiri, G. H., &#38; Hof, B. (2019). Dynamics of viscoelastic
    pipe flow at low Reynolds numbers in the maximum drag reduction limit. <i>Journal
    of Fluid Mechanics</i>. CUP. <a href="https://doi.org/10.1017/jfm.2019.486">https://doi.org/10.1017/jfm.2019.486</a>
  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.” <i>Journal
    of Fluid Mechanics</i>. CUP, 2019. <a href="https://doi.org/10.1017/jfm.2019.486">https://doi.org/10.1017/jfm.2019.486</a>.
  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,” <i>Journal
    of Fluid Mechanics</i>, vol. 874. CUP, 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.” <i>Journal of Fluid Mechanics</i>,
    vol. 874, CUP, 2019, pp. 699–719, doi:<a href="https://doi.org/10.1017/jfm.2019.486">10.1017/jfm.2019.486</a>.
  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: 2023-09-06T15:36:36Z
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: CUP
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: c635000d-4b10-11ee-a964-aac5a93f6ac1
volume: 874
year: '2019'
...
---
_id: '6413'
abstract:
- lang: eng
  text: Phase-field methods have long been used to model the flow of immiscible fluids.
    Their ability to naturally capture interface topological changes is widely recognized,
    but their accuracy in simulating flows of real fluids in practical geometries
    is not established. We here quantitatively investigate the convergence of the
    phase-field method to the sharp-interface limit with simulations of two-phase
    pipe flow. We focus on core-annular flows, in which a highly viscous fluid is
    lubricated by a less viscous fluid, and validate our simulations with an analytic
    laminar solution, a formal linear stability analysis and also in the fully nonlinear
    regime. We demonstrate the ability of the phase-field method to accurately deal
    with non-rectangular geometry, strong advection, unsteady fluctuations and large
    viscosity contrast. We argue that phase-field methods are very promising for quantitatively
    studying moderately turbulent flows, especially at high concentrations of the
    disperse phase.
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Baofang
  full_name: Song, Baofang
  last_name: Song
- first_name: Carlos
  full_name: Plana, Carlos
  last_name: Plana
- 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: Song B, Plana C, Lopez Alonso JM, Avila M. Phase-field simulation of core-annular
    pipe flow. <i>International Journal of Multiphase Flow</i>. 2019;117:14-24. doi:<a
    href="https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027">10.1016/j.ijmultiphaseflow.2019.04.027</a>
  apa: Song, B., Plana, C., Lopez Alonso, J. M., &#38; Avila, M. (2019). Phase-field
    simulation of core-annular pipe flow. <i>International Journal of Multiphase Flow</i>.
    Elsevier. <a href="https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027">https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027</a>
  chicago: Song, Baofang, Carlos Plana, Jose M Lopez Alonso, and Marc Avila. “Phase-Field
    Simulation of Core-Annular Pipe Flow.” <i>International Journal of Multiphase
    Flow</i>. Elsevier, 2019. <a href="https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027">https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027</a>.
  ieee: B. Song, C. Plana, J. M. Lopez Alonso, and M. Avila, “Phase-field simulation
    of core-annular pipe flow,” <i>International Journal of Multiphase Flow</i>, vol.
    117. Elsevier, pp. 14–24, 2019.
  ista: Song B, Plana C, Lopez Alonso JM, Avila M. 2019. Phase-field simulation of
    core-annular pipe flow. International Journal of Multiphase Flow. 117, 14–24.
  mla: Song, Baofang, et al. “Phase-Field Simulation of Core-Annular Pipe Flow.” <i>International
    Journal of Multiphase Flow</i>, vol. 117, Elsevier, 2019, pp. 14–24, doi:<a href="https://doi.org/10.1016/j.ijmultiphaseflow.2019.04.027">10.1016/j.ijmultiphaseflow.2019.04.027</a>.
  short: B. Song, C. Plana, J.M. Lopez Alonso, M. Avila, International Journal of
    Multiphase Flow 117 (2019) 14–24.
date_created: 2019-05-13T07:58:35Z
date_published: 2019-08-01T00:00:00Z
date_updated: 2023-08-25T10:19:55Z
day: '01'
department:
- _id: BjHo
doi: 10.1016/j.ijmultiphaseflow.2019.04.027
external_id:
  arxiv:
  - '1902.07351'
  isi:
  - '000474496000002'
intvolume: '       117'
isi: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1902.07351
month: '08'
oa: 1
oa_version: Preprint
page: 14-24
publication: International Journal of Multiphase Flow
publication_identifier:
  issn:
  - '03019322'
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Phase-field simulation of core-annular pipe flow
type: journal_article
user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 117
year: '2019'
...
---
_id: '328'
abstract:
- lang: eng
  text: The drag of turbulent flows can be drastically decreased by adding small amounts
    of high molecular weight polymers. While drag reduction initially increases with
    polymer concentration, it eventually saturates to what is known as the maximum
    drag reduction (MDR) asymptote; this asymptote is generally attributed to the
    dynamics being reduced to a marginal yet persistent state of subdued turbulent
    motion. Contrary to this accepted view, we show that, for an appropriate choice
    of parameters, polymers can reduce the drag beyond the suggested asymptotic limit,
    eliminating turbulence and giving way to laminar flow. At higher polymer concentrations,
    however, the laminar state becomes unstable, resulting in a fluctuating flow with
    the characteristic drag of the MDR asymptote. Our findings indicate that the asymptotic
    state is hence dynamically disconnected from ordinary turbulence. © 2018 American
    Physical Society.
acknowledged_ssus:
- _id: SSU
acknowledgement: The authors thank Philipp Maier and the IST Austria workshop for
  their dedicated technical support.
article_number: '124501'
article_processing_charge: No
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: 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, Hof B. Exceeding the asymptotic limit of polymer
    drag reduction. <i>Physical Review Letters</i>. 2018;120(12). doi:<a href="https://doi.org/10.1103/PhysRevLett.120.124501">10.1103/PhysRevLett.120.124501</a>
  apa: Choueiri, G. H., Lopez Alonso, J. M., &#38; Hof, B. (2018). Exceeding the asymptotic
    limit of polymer drag reduction. <i>Physical Review Letters</i>. American Physical
    Society. <a href="https://doi.org/10.1103/PhysRevLett.120.124501">https://doi.org/10.1103/PhysRevLett.120.124501</a>
  chicago: Choueiri, George H, Jose M Lopez Alonso, and Björn Hof. “Exceeding the
    Asymptotic Limit of Polymer Drag Reduction.” <i>Physical Review Letters</i>. American
    Physical Society, 2018. <a href="https://doi.org/10.1103/PhysRevLett.120.124501">https://doi.org/10.1103/PhysRevLett.120.124501</a>.
  ieee: G. H. Choueiri, J. M. Lopez Alonso, and B. Hof, “Exceeding the asymptotic
    limit of polymer drag reduction,” <i>Physical Review Letters</i>, vol. 120, no.
    12. American Physical Society, 2018.
  ista: Choueiri GH, Lopez Alonso JM, Hof B. 2018. Exceeding the asymptotic limit
    of polymer drag reduction. Physical Review Letters. 120(12), 124501.
  mla: Choueiri, George H., et al. “Exceeding the Asymptotic Limit of Polymer Drag
    Reduction.” <i>Physical Review Letters</i>, vol. 120, no. 12, 124501, American
    Physical Society, 2018, doi:<a href="https://doi.org/10.1103/PhysRevLett.120.124501">10.1103/PhysRevLett.120.124501</a>.
  short: G.H. Choueiri, J.M. Lopez Alonso, B. Hof, Physical Review Letters 120 (2018).
date_created: 2018-12-11T11:45:51Z
date_published: 2018-03-19T00:00:00Z
date_updated: 2023-10-10T13:27:44Z
day: '19'
department:
- _id: BjHo
doi: 10.1103/PhysRevLett.120.124501
ec_funded: 1
external_id:
  isi:
  - '000427804000005'
intvolume: '       120'
isi: 1
issue: '12'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1703.06271
month: '03'
oa: 1
oa_version: Preprint
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '291734'
  name: International IST Postdoc Fellowship Programme
- _id: 25152F3A-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '306589'
  name: Decoding the complexity of turbulence at its origin
publication: Physical Review Letters
publication_status: published
publisher: American Physical Society
publist_id: '7537'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Exceeding the asymptotic limit of polymer drag reduction
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 120
year: '2018'
...
---
_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. <i>Journal of Fluid Mechanics</i>. 2017;817:21-34. doi:<a href="https://doi.org/10.1017/jfm.2017.109">10.1017/jfm.2017.109</a>
  apa: Lopez Alonso, J. M., &#38; Avila, M. (2017). Boundary layer turbulence in experiments
    on quasi Keplerian flows. <i>Journal of Fluid Mechanics</i>. Cambridge University
    Press. <a href="https://doi.org/10.1017/jfm.2017.109">https://doi.org/10.1017/jfm.2017.109</a>
  chicago: Lopez Alonso, Jose M, and Marc Avila. “Boundary Layer Turbulence in Experiments
    on Quasi Keplerian Flows.” <i>Journal of Fluid Mechanics</i>. Cambridge University
    Press, 2017. <a href="https://doi.org/10.1017/jfm.2017.109">https://doi.org/10.1017/jfm.2017.109</a>.
  ieee: J. M. Lopez Alonso and M. Avila, “Boundary layer turbulence in experiments
    on quasi Keplerian flows,” <i>Journal of Fluid Mechanics</i>, 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.” <i>Journal of Fluid Mechanics</i>, vol. 817, Cambridge
    University Press, 2017, pp. 21–34, doi:<a href="https://doi.org/10.1017/jfm.2017.109">10.1017/jfm.2017.109</a>.
  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'
...