Fast dynamo action in unsteady flows and maps in three dimensions

Bruce J Bayly, S. Childress

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

Unsteady fast dynamo action is obtained in a family of stretch-fold-shear maps applied to a spatially periodic magnetic field in three dimensions. Exponential growth of a mean field in the limit of vanishing diffusivity is demonstrated by a numerical method which alternates instantaneous deformations with molecular diffusion over a finite time interval. Analysis indicates that the dynamo is a coherent feature of the large scales, essentially independent of the cascade of structure to small scales.

Original languageEnglish (US)
Pages (from-to)1573-1576
Number of pages4
JournalPhysical Review Letters
Volume59
Issue number14
DOIs
StatePublished - 1987
Externally publishedYes

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unsteady flow
molecular diffusion
diffusivity
cascades
shear
intervals
magnetic fields

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Fast dynamo action in unsteady flows and maps in three dimensions. / Bayly, Bruce J; Childress, S.

In: Physical Review Letters, Vol. 59, No. 14, 1987, p. 1573-1576.

Research output: Contribution to journalArticle

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