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Generation of magnetic fields by convection

Published online by Cambridge University Press:  29 March 2006

F. H. Busse
Affiliation:
Department of Planetary and Space Science, University of California, Los Angeles

Abstract

The nonlinear hydromagnetic dynamo problem is investigated for the case of convection in a layer of an electrically conducting fluid heated from below. It is shown that two-dimensional convection rolls in conjunction with a longitudinal mean flow are capable of amplifying a magnetic field in the form of a wave propagating in the longitudinal direction. The action of the Lorentz forces causes a reduction of the amplitude of convection with the consequence that the energy of the magnetic field cannot grow beyond an equilibrium value which is determined as a function of the parameters of the problem. The analysis is based on an expansion in powers of the longitudinal wavenumber β of the magnetic field and applies in the case of large values of the magnetic Prandtl number.

Type
Research Article
Copyright
© 1973 Cambridge University Press

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