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A study of fast dynamo action in chaotic helical cells

Published online by Cambridge University Press:  26 April 2006

I. Klapper
I. Klapper
Affiliation:
New York University, Courant Institute of Mathematical Sciences, 251 Mercer Street, New York, NY 10012, USA
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Abstract

Fast dynamo action in a chaotic time-periodic flow is investigated. Chaotic motion is created by perturbing a spatially periodic array of helical cells similar to Roberts’ cells, leading to an identifiable stretch–fold–shear fast dynamo mechanism. Using the stochastic Wiener bundle method to treat diffusion exactly, numerical results are presented suggesting fast dynamo action. A new numerical method for modelling the role of small magnetic diffusivity is introduced and results are compared with those calculated using the Wiener bundle method. Implications for the role of diffusion in the fast dynamo process are investigated. Finally the relation of the new method to a previously used ‘flux growth’ method are discussed.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 239 , June 1992 , pp. 359 - 381
Copyright
© 1992 Cambridge University Press

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