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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Online Access: | http://dx.doi.org/10.1017/jfm.2017.117 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112017001173 |
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crcambridgeupr:10.1017/jfm.2017.117 2024-03-03T08:38:49+00:00 Unsteadily manipulating internal flow barriers Balasuriya, Sanjeeva 2017 http://dx.doi.org/10.1017/jfm.2017.117 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112017001173 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Journal of Fluid Mechanics volume 818, page 382-406 ISSN 0022-1120 1469-7645 Mechanical Engineering Mechanics of Materials Condensed Matter Physics journal-article 2017 crcambridgeupr https://doi.org/10.1017/jfm.2017.117 2024-02-08T08:37:27Z 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. Article in Journal/Newspaper Antarc* Antarctic Cambridge University Press Antarctic The Antarctic Journal of Fluid Mechanics 818 382 406 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
topic |
Mechanical Engineering Mechanics of Materials Condensed Matter Physics |
spellingShingle |
Mechanical Engineering Mechanics of Materials Condensed Matter Physics Balasuriya, Sanjeeva Unsteadily manipulating internal flow barriers |
topic_facet |
Mechanical Engineering Mechanics of Materials Condensed Matter Physics |
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. |
format |
Article in Journal/Newspaper |
author |
Balasuriya, Sanjeeva |
author_facet |
Balasuriya, Sanjeeva |
author_sort |
Balasuriya, Sanjeeva |
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 (CUP) |
publishDate |
2017 |
url |
http://dx.doi.org/10.1017/jfm.2017.117 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112017001173 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Journal of Fluid Mechanics volume 818, page 382-406 ISSN 0022-1120 1469-7645 |
op_rights |
https://www.cambridge.org/core/terms |
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_ |
1792507284623982592 |