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Mean induction and diffusion: the influence of spatial coherence

Published online by Cambridge University Press:  25 May 2009

ALICE COURVOISIER ,
DAVID W. HUGHES  and
STEVEN M. TOBIAS
ALICE COURVOISIER*
Affiliation:
Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK
DAVID W. HUGHES
Affiliation:
Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK
STEVEN M. TOBIAS
Affiliation:
Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK
*
†Email address for correspondence: [email protected]
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Abstract

Within the same framework we calculate the mean induction of a magnetic field and the mean diffusivity of a passive scalar, for two families of flows in which the degree of spatial decorrelation can be systematically adjusted. We investigate the dependence of these quantities both on the spatial decoherence and on the molecular diffusivity. We demonstrate that for flows with similar global properties, the mean induction is dramatically reduced as the flows become less spatially correlated; the mean diffusivity, on the other hand, shows no significant or systematic variation.

Type
Papers
Information
Journal of Fluid Mechanics , Volume 627 , 25 May 2009 , pp. 403 - 421
Copyright
Copyright © Cambridge University Press 2009

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