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Bounds for growth rates for dynamos with shear

Published online by Cambridge University Press:  06 March 2012

M. R. E. Proctor
M. R. E. Proctor*
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA, UK
*
†Email address for correspondence: [email protected]
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Abstract

In several recent papers it has been established that the addition of a shear flow to a small-scale velocity field can enhance dynamo action. Many of these studies show that the growth rate of the magnetic energy increases linearly with the shear amplitude over a range of shears. In this paper it is shown analytically that for a variety of dynamo models and very large shear amplitudes , growth rates increase no faster than under plausible conditions on the amplitude of the remaining velocity.

JFM classification

MHD and Electrohydrodynamics: Dynamo theory
Type
Papers
Information
Journal of Fluid Mechanics , Volume 697 , 25 April 2012 , pp. 504 - 510
Copyright
Copyright © Cambridge University Press 2012

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References

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