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The nonlinear evolution of magnetic instabilities in a rapidly rotating annulus

Published online by Cambridge University Press:  26 April 2006

Kenneth A. Hutcheson  and
David R. Fearn
Kenneth A. Hutcheson
Affiliation:
Department of Mathematics, University Gardens, University of Glasgow, Glasgow G12 8QW, UK
David R. Fearn
Affiliation:
Department of Mathematics, University Gardens, University of Glasgow, Glasgow G12 8QW, UK
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Abstract

A numerical investigation of the stability of an axisymmetric magnetic field is discussed. The magnetic field permeates a finitely conducting fluid contained within a rapidly rotating cylindrical annulus. The fluid is incompressible and viscid. The evolution of a non-axisymmetric perturbation to the axisymmetric magnetic field is governed by the momentum and induction equations which are integrated using a spectral timestep method. We follow the growth of the perturbation to finite amplitude and find that the character of the solution is dominated by the most unstable axially dependent mode found from the linear theory.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 291 , 25 May 1995 , pp. 343 - 368
Copyright
© 1995 Cambridge University Press

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