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Fast and furious dynamo action in the anisotropic dynamo

Published online by Cambridge University Press:  11 May 2022

Franck Plunian Open the ORCID record for Franck Plunian [Opens in a new window]  and
Thierry Alboussière Open the ORCID record for Thierry Alboussière [Opens in a new window]
Franck Plunian*
Affiliation:
Université Grenoble Alpes, University of Savoie Mont Blanc, CNRS, IRD, Université Gustave Eiffel, ISTerre, 38000 Grenoble, France
Thierry Alboussière
Affiliation:
Université Lyon 1, ENS de Lyon, CNRS, Laboratoire de Géologie de Lyon, Lyon 69622, France
*
†Email address for correspondence: Franck.Plunian@univ-grenoble-alpes.fr
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Abstract

In the limit of large magnetic Reynolds numbers, it is shown that a smooth differential rotation can lead to fast dynamo action, provided that the electrical conductivity or magnetic permeability is anisotropic. If the shear is infinite, for example between two rotating solid bodies, the anisotropic dynamo becomes furious, meaning that the magnetic growth rate increases toward infinity with an increasing magnetic Reynolds number.

JFM classification

Geophysical and Geological Flows: Geodynamo MHD and Electrohydrodynamics: Dynamo theory
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 941 , 25 June 2022 , A66
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Copyright
© The Author(s), 2022. Published by Cambridge University Press

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References

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