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Compressible magnetoconvection in oblique fields: linearized theory and simple nonlinear models

Published online by Cambridge University Press:  26 April 2006

P. C. Matthews ,
N. E. Hurlburt ,
M. R. E. Proctor  and
D. P. Brownjohn
P. C. Matthews
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK
N. E. Hurlburt
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK Present address: Lockheed Palo Alto Research Laboratory.
M. R. E. Proctor
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK
D. P. Brownjohn
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK
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Abstract

The linear stability of a layer of compressible fluid, permeated by an oblique magnetic field, is discussed. It is shown that regardless of the system parameters, all bifurcations generically lead to travelling waves. Wave speeds and direction of the wave propagation are investigated. Symmetry arguments are used to show that when the field is almost vertical, waves with a wave vector aligned with the tilt are preferred over those with a wave vector perpendicular to the tilt. The nonlinear development of the travelling waves is explored using simple model equations.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 240 , July 1992 , pp. 559 - 569
Copyright
© 1992 Cambridge University Press

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