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| Titel |
MEAN FLOW GENERATION AND INERTIAL WAVE ATTRACTORS IN A LIBRATING ANNULUS: DNS and Theory |
| VerfasserIn |
Marten Klein, Abouzar Ghasemi V., Torsten Seelig, Ion Dan Borcia, Uwe Harlander, Andreas Will |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250114821
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| Publikation (Nr.) |
 EGU/EGU2015-15640.pdf |
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| Zusammenfassung |
| Rotation $\Omega_0$ is one of the most important system parameters in
geophysical fluid dynamics (GFD) due to stratification of angular
momentum. Oscillatory motion (libration) of the fluid over solid
surfaces is generated in many systems by harmonic forces, usually
resulting from rotation of the fluid in a homogeneous gravitational
and/or electromagnetic field. \\ Small amplitudes of libration can
excite inertial waves, which are shear waves, band-limited to
frequencies $0 < \omega < 2\Omega_0$ and dispersive with respect to
direction. Large amplitudes of libration can excite turbulent motion
(G\"{o}rtler vortices), which is transpored into the bulk by the
Coriolis force. Waves and vortices may take part in the
redistribution of kinetic energy and angular momentum. Complex system
responses are possible so that it is of fundamental interest to
understand inertial waves and related turbulent phenomena in order to
quantify their relevance for applications.
Direct numerical simulations (DNS) of an axially rotating annulus have
been carried out for straight and inclined cylinder walls, with and
without lids. The system was perturbed by libration of inner and/or
outer cylinder walls and/or of the lids with small libration amplitude
$\epsilon\leq 0.1$ and frequency $\omega0.3$ and frequencies
$\omega |
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