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Critical torsional modes of convection in rotating fluid spheres at high Taylor numbers

Published online by Cambridge University Press:  15 February 2016

Juan Sánchez
Affiliation:
Physics Department, Universitat Politècnica de Catalunya Jordi Girona Salgado 3, Campus Nord, Mòdul B4, 08034 Barcelona, Spain
Ferran Garcia
Affiliation:
Physics Department, Universitat Politècnica de Catalunya Jordi Girona Salgado 3, Campus Nord, Mòdul B4, 08034 Barcelona, Spain
Marta Net*
Affiliation:
Physics Department, Universitat Politècnica de Catalunya Jordi Girona Salgado 3, Campus Nord, Mòdul B4, 08034 Barcelona, Spain
*
Email address for correspondence: marta.net@upc.edu

Abstract

A numerical study of the onset of convection in rotating internally heated self-gravitating fluid spheres is presented. The exploration of the stability of the conduction state versus the Taylor and Prandtl numbers supplies a detailed idea of the laws that fulfil the four types of solutions obtained at low Prandtl numbers. The main result found is that axisymmetric (torsional) modes of convection are preferred at high Taylor numbers in the zero-Prandtl-number limit. This instability appears at low Rayleigh numbers and gives rise to an oscillating single vortex of very high frequency.

Type
Rapids
Copyright
© 2016 Cambridge University Press 

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