Unsteadily manipulating internal flow barriers
Typical flows contain internal flow barriers: specialised time-moving Lagrangian entities which demarcate distinct motions. Examples include the boundary between an oceanic eddy and a nearby jet, the edge of the Antarctic circumpolar vortex or the interface between two fluids which are to be mixed t...
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Cambridge University Press
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ftunivadelaidedl:oai:digital.library.adelaide.edu.au:2440/106154 2023-12-17T10:21:57+01:00 Unsteadily manipulating internal flow barriers Balasuriya, S. 2017 http://hdl.handle.net/2440/106154 https://doi.org/10.1017/jfm.2017.117 en eng Cambridge University Press http://purl.org/au-research/grants/arc/FT130100484 Journal of Fluid Mechanics, 2017; 818:382-406 0022-1120 1469-7645 http://hdl.handle.net/2440/106154 doi:10.1017/jfm.2017.117 Balasuriya, S. [0000-0002-3261-7940] © Cambridge University Press 2017 http://dx.doi.org/10.1017/jfm.2017.117 Flow control mixing nonlinear dynamical systems Journal article 2017 ftunivadelaidedl https://doi.org/10.1017/jfm.2017.117 2023-11-20T23:21:50Z Typical flows contain internal flow barriers: specialised time-moving Lagrangian entities which demarcate distinct motions. Examples include the boundary between an oceanic eddy and a nearby jet, the edge of the Antarctic circumpolar vortex or the interface between two fluids which are to be mixed together in an microfluidic assay. The ability to control the locations of these barriers in a user-specified time-varying (unsteady) way can profoundly impact fluid transport between the coherent structures which are separated by the barriers. A condition on the unsteady Eulerian velocity required to achieve this objective is explicitly derived, thereby solving an ‘inverse Lagrangian coherent structure’ problem. This is an important first step in developing flow-barrier control in realistic flows, and in providing a postprocessing tool for observational/experimental velocity data. The excellent accuracy of the method is demonstrated using the Kelvin–Stuart cats-eyes flow and the unsteady double gyre, utilising finite-time Lyapunov exponents. Sanjeeva Balasuriya Article in Journal/Newspaper Antarc* Antarctic The University of Adelaide: Digital Library Antarctic The Antarctic Journal of Fluid Mechanics 818 382 406 |
institution |
Open Polar |
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The University of Adelaide: Digital Library |
op_collection_id |
ftunivadelaidedl |
language |
English |
topic |
Flow control mixing nonlinear dynamical systems |
spellingShingle |
Flow control mixing nonlinear dynamical systems Balasuriya, S. Unsteadily manipulating internal flow barriers |
topic_facet |
Flow control mixing nonlinear dynamical systems |
description |
Typical flows contain internal flow barriers: specialised time-moving Lagrangian entities which demarcate distinct motions. Examples include the boundary between an oceanic eddy and a nearby jet, the edge of the Antarctic circumpolar vortex or the interface between two fluids which are to be mixed together in an microfluidic assay. The ability to control the locations of these barriers in a user-specified time-varying (unsteady) way can profoundly impact fluid transport between the coherent structures which are separated by the barriers. A condition on the unsteady Eulerian velocity required to achieve this objective is explicitly derived, thereby solving an ‘inverse Lagrangian coherent structure’ problem. This is an important first step in developing flow-barrier control in realistic flows, and in providing a postprocessing tool for observational/experimental velocity data. The excellent accuracy of the method is demonstrated using the Kelvin–Stuart cats-eyes flow and the unsteady double gyre, utilising finite-time Lyapunov exponents. Sanjeeva Balasuriya |
format |
Article in Journal/Newspaper |
author |
Balasuriya, S. |
author_facet |
Balasuriya, S. |
author_sort |
Balasuriya, S. |
title |
Unsteadily manipulating internal flow barriers |
title_short |
Unsteadily manipulating internal flow barriers |
title_full |
Unsteadily manipulating internal flow barriers |
title_fullStr |
Unsteadily manipulating internal flow barriers |
title_full_unstemmed |
Unsteadily manipulating internal flow barriers |
title_sort |
unsteadily manipulating internal flow barriers |
publisher |
Cambridge University Press |
publishDate |
2017 |
url |
http://hdl.handle.net/2440/106154 https://doi.org/10.1017/jfm.2017.117 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
http://dx.doi.org/10.1017/jfm.2017.117 |
op_relation |
http://purl.org/au-research/grants/arc/FT130100484 Journal of Fluid Mechanics, 2017; 818:382-406 0022-1120 1469-7645 http://hdl.handle.net/2440/106154 doi:10.1017/jfm.2017.117 Balasuriya, S. [0000-0002-3261-7940] |
op_rights |
© Cambridge University Press 2017 |
op_doi |
https://doi.org/10.1017/jfm.2017.117 |
container_title |
Journal of Fluid Mechanics |
container_volume |
818 |
container_start_page |
382 |
op_container_end_page |
406 |
_version_ |
1785541048863293440 |