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Lagrangian approach to the mean-field electrodynamics for turbulent fluids with arbitrary conductivities

Published online by Cambridge University Press:  26 April 2006

L. L. Kichatinov
L. L. Kichatinov
Affiliation:
Siberian Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, PO Box 4, Irkutsk 33, USSR
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Abstract

A modification is made to the traditional Lagrangian approach to the derivation of the mean EMF of turbulent fluids which allows for finite conductivities. Consideration is confined to the case of homogeneous, isotropic but generally mirrornon-invariant and compressible turbulence. The eddy magnetic diffusivity and the coefficient α of the alpha-effect are expressed in terms of statistical moments of displacements of adjacent particles which undergo convective transport and microscopic diffusion in a turbulent flow. These expressions, being valid for arbitrary conductivities, reproduce known results in the cases of both very large and very small magnetic Reynolds numbers. Difficulties and advantages of the use of the results obtained for evaluations of the mean EMF are discussed.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 208 , November 1989 , pp. 115 - 126
Copyright
© 1989 Cambridge University Press

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