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Magnetic flux ropes and convection

Published online by Cambridge University Press:  12 April 2006

D. J. Galloway ,
M. R. E. Proctor  and
N. O. Weiss
D. J. Galloway
Affiliation:
Astronomy Centre, University of Sussex, Brighton, England
M. R. E. Proctor
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, England
N. O. Weiss
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, England
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Abstract

Three-dimensional cellular convection concentrates magnetic flux into ropes when the magnetic Reynolds number is large. Amplification of the magnetic field is limited by the Lorentz force and the maximum field in a flux rope can be estimated. Boundary-layer analysis yields a completely self-consistent solution for a model of convection driven by imposed horizontal temperature gradients, and the transition from a kinematic to a dynamic regime can be followed in detail. The maximum value of the amplified field is proportional to the square root of the ratio of the viscous to the magnetic diffusivity.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 87 , Issue 2 , 26 July 1978 , pp. 243 - 261
Copyright
© 1978 Cambridge University Press

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