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The dynamic effect of flux ropes on Rayleigh-Bénard convection

Published online by Cambridge University Press:  19 April 2006

M. R. E. Proctor  and
D. J. Galloway
M. R. E. Proctor
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge
D. J. Galloway
Affiliation:
Astronomy Centre, University of Sussex, Brighton Present address: High Altitude Observatory, Boulder, Colorado.
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Abstract

The interaction between magnetic fields and convection in a fluid heated from below is investigated in an axisymmetric cylindrical geometry. When Rm, the magnetic Reynolds number, is large the field is concentrated into a thin rope on the axis of the cylinder. For weak magnetic fields a larger Rayleigh number is necessary to produce a flux rope than that needed for infinitesimal convection. For larger total fluxes, however, the opposite is true and the system is subcritically unstable to steady motions. The results are contrasted with those found by Busse (1975) for the corresponding two-dimensional roll problem.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 90 , Issue 2 , 29 January 1979 , pp. 273 - 287
Copyright
© 1979 Cambridge University Press

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