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Axisymmetric magnetoconvection in a twisted field

Published online by Cambridge University Press:  26 April 2006

C. A. Jones  and
D. J. Galloway
C. A. Jones
Affiliation:
Department of Mathematics, University of Exeter EX4 4QE, UK
D. J. Galloway
Affiliation:
School of Mathematics and Statistics, University of Sydney, NSW 2006, Australia
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Abstract

The process of flux rope formation in a convecting cell is studied. The magnetic field has both a meridional and an azimuthal component, and so corresponds to a twisted field. Convection occurs in this cylindrical cell because of heating from below, and is assumed to take an axisymmetric form. Only the Boussinesq problem is studied here, but both the kinematic and the dynamic regimes are considered.

The two cases where the twisted field is due to (a) an imposed flux of vertical current and (b) an imposed flux of vertical vorticity are considered. Strongly twisted ropes can be generated more easily in case (b) than in case (a).

We show that convection can produce ropes twisted in the opposite direction from that of the initial field. We also find that solutions can be oscillatory even when linear theory predicts steady solutions.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 253 , August 1993 , pp. 297 - 326
Copyright
© 1993 Cambridge University Press

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