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A fast kinematic dynamo in two-dimensional time-dependent flows

Published online by Cambridge University Press:  26 April 2006

Niels F. Otani
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Abstract

A time-continuous, constant-resistivity version of the fast dynamo model introduced by Bayly & Childress (1988) is studied numerically. The expected dynamo mechanism in this context is described and is shown to be operative in the simulations. Exponential growth of the fastest growing mode is observed, with the growth rate for the smallest resistivity attempted (1/Rm = 10-4) agreeing well with the Bayly–Childress model. It is argued, based on the long- and short-wavelength behaviour of the mode for different resistivities, that the growth rates obtained for the Rm = 104 case should persist as Rm → ∞.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 253 , August 1993 , pp. 327 - 340
Copyright
© 1993 Cambridge University Press

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