An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies
A series of laboratory experiments has been carried out in a thermally driven rotating annulus to study the onset of baroclinic instability, using horizontal and uniformly sloping bottom topographies. Different wave flow regimes have been identified and their phase boundaries – expressed in terms of...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2014-02-01
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| Series: | Nonlinear Processes in Geophysics |
| Online Access: | http://www.nonlin-processes-geophys.net/21/237/2014/npg-21-237-2014.pdf |
| _version_ | 1819111913667166208 |
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| author | M. Vincze U. Harlander Th. von Larcher C. Egbers |
| author_facet | M. Vincze U. Harlander Th. von Larcher C. Egbers |
| author_sort | M. Vincze |
| collection | DOAJ |
| description | A series of laboratory experiments has been carried out in a thermally driven
rotating annulus to study the onset of baroclinic instability, using
horizontal and uniformly sloping bottom topographies. Different wave flow
regimes have been identified and their phase boundaries – expressed in terms
of appropriate non-dimensional parameters – have been compared to the recent
numerical linear stability analysis of von Larcher et al. (2013). In the flat
bottom case, the numerically predicted alignment of the boundary between the
axisymmetric and the regular wave flow regime was found to be consistent with
the experimental results. However, once the sloping bottom end wall was
introduced, the detected behaviour was qualitatively different from that of
the simulations. This disagreement is thought to be the consequence of
nonlinear wave–wave interactions that could not be resolved in the framework
of the numerical study. This argument is supported by the observed
development of interference vacillation in the runs with sloping bottom, a
mixed flow state in which baroclinic wave modes exhibiting different drift
rates and amplitudes can co-exist. |
| first_indexed | 2024-12-22T04:05:10Z |
| format | Article |
| id | doaj.art-d2ad3b2e670f4a3eb7f4044c93f1c291 |
| institution | Directory Open Access Journal |
| issn | 1023-5809 1607-7946 |
| language | English |
| last_indexed | 2024-12-22T04:05:10Z |
| publishDate | 2014-02-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Nonlinear Processes in Geophysics |
| spelling | doaj.art-d2ad3b2e670f4a3eb7f4044c93f1c2912022-12-21T18:39:39ZengCopernicus PublicationsNonlinear Processes in Geophysics1023-58091607-79462014-02-0121123725010.5194/npg-21-237-2014An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographiesM. Vincze0U. Harlander1Th. von Larcher2C. Egbers3Department of Aerodynamics and Fluid Mechanics, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, GermanyDepartment of Aerodynamics and Fluid Mechanics, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, GermanyInstitute for Mathematics, Freie Universität Berlin, Berlin, GermanyDepartment of Aerodynamics and Fluid Mechanics, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, GermanyA series of laboratory experiments has been carried out in a thermally driven rotating annulus to study the onset of baroclinic instability, using horizontal and uniformly sloping bottom topographies. Different wave flow regimes have been identified and their phase boundaries – expressed in terms of appropriate non-dimensional parameters – have been compared to the recent numerical linear stability analysis of von Larcher et al. (2013). In the flat bottom case, the numerically predicted alignment of the boundary between the axisymmetric and the regular wave flow regime was found to be consistent with the experimental results. However, once the sloping bottom end wall was introduced, the detected behaviour was qualitatively different from that of the simulations. This disagreement is thought to be the consequence of nonlinear wave–wave interactions that could not be resolved in the framework of the numerical study. This argument is supported by the observed development of interference vacillation in the runs with sloping bottom, a mixed flow state in which baroclinic wave modes exhibiting different drift rates and amplitudes can co-exist.http://www.nonlin-processes-geophys.net/21/237/2014/npg-21-237-2014.pdf |
| spellingShingle | M. Vincze U. Harlander Th. von Larcher C. Egbers An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies Nonlinear Processes in Geophysics |
| title | An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies |
| title_full | An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies |
| title_fullStr | An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies |
| title_full_unstemmed | An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies |
| title_short | An experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies |
| title_sort | experimental study of regime transitions in a differentially heated baroclinic annulus with flat and sloping bottom topographies |
| url | http://www.nonlin-processes-geophys.net/21/237/2014/npg-21-237-2014.pdf |
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