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| Titel |
Onset of convection in an anisotropic viscous fluid and implications for geophysical flows |
| VerfasserIn |
Laurent Pouilloux, Stephane Labrosse, Edouard Kaminski |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250041493
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| Zusammenfassung |
| The dynamics of planetary bodies is strongly dependent on the rheological properties of
polycrystalline aggregates. The deformation process, specifically dislocation creep, that
occurs in ice or olivine leads to the formation of a texture, yielding to anisotropic properties
of the material. Until now, anisotropic viscosity has received little attention when related to
complex geophysical flow, mostly because of the mathematical complexity of the description
of the physical properties.
In this study, we propose to use an original mathematical technique derived from
anisotropic elasticity to explore the range of effects we can expect when considering the onset
of convection in an anisotropic viscous fluid. Using linear stability analysis, we determine the
potential effect of anisotropic viscosity on the critical parameters for the onset : the critical
Rayleigh number Rac and the critical wave number ac, and the most unstable roll direction
αc which is specific to anisotropic convection.
Consequences for the dynamics of icy satellites and small-scale convection beneath the
oceanic lithosphere will be discussed. |
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