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Dynamo properties of the turbulent velocity field of a saturated dynamo

Published online by Cambridge University Press:  12 February 2009

FAUSTO CATTANEO  and
STEVEN M. TOBIAS
FAUSTO CATTANEO
Affiliation:
Department of Astronomy and Astrophysics and The Computation Institute, University of Chicago, Chicago, IL 60637, USA
STEVEN M. TOBIAS*
Affiliation:
Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK
*
†Email address for correspondence: smt@amsta.leeds.ac.uk
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Abstract

In order better to understand how dynamo systems saturate, we study the kinematic dynamo properties of velocity fields that arise from nonlinearly saturated dynamos. The technique is implemented by solving concurrently, in addition to the momentum equation, two induction equations, one for the actual magnetic field and one for an independent passive vector field. We apply this technique to two illustrative examples: convectively driven turbulence and turbulence represented by a shell model. In all cases we find that the velocity remains an efficient kinematic dynamo even after nonlinear saturation occurs. We discuss the implications to the process of dynamo saturation.

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Type
Papers
Information
Journal of Fluid Mechanics , Volume 621 , 25 February 2009 , pp. 205 - 214
Copyright
Copyright © Cambridge University Press 2009

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References

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