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Dynamo action associated with random waves in a rotating stratified fluid

Published online by Cambridge University Press:  19 April 2006

M. Walder ,
W. Deinzer  and
M. Stix
M. Walder
Affiliation:
Lehrstuhl für Theoretische Astrophysik, Universität Tübingen, West Germany
W. Deinzer
Affiliation:
Universitäts-Sternwarte, Göttingen, West Germany
M. Stix
Affiliation:
Kiepenheuer-Institut für Sonnenphysik, Freiburg, West Germany
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Abstract

A random superposition of waves in a rotating, stratified, electrically conducting fluid leads to dynamo action in the sense that it yields a mean electric field having a component parallel to the mean magnetic field (‘α-effect’). Using Fourier analysis methods, we derive an explicit expression for the mean electric field. The α-effect has tensor form. We obtain a finite α-tensor even in a case of vanishing mean helicity. The result is discussed in the context of the solar turbulent dynamo.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 96 , Issue 1 , 16 January 1980 , pp. 207 - 222
Copyright
© 1980 Cambridge University Press

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