Flow helicity in a simplified statistical model of a fast dynamo

Eun Jin Kim, David W. Hughes

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

The role of kinetic helicity in small-scale fast dynamo action is investigated by employing a simple statistical model for the underlying flow with statistics that are Gaussian distributed, temporally delta-correlated and spatially homogeneous and isotropic. In order to focus on small-scale dynamo action we restrict our attention to flows possessing no net kinetic helicity. With the help of a diagrammatic technique and a numerical calculation we show that the dynamo growth rate is independent of the kinetic helicity as the magnetic Reynolds number Rm → ∞. It is indicated that the latter enhances the growth of the magnetic energy only for finite Rm.

Original languageEnglish
Pages (from-to)211-218
Number of pages8
JournalPhysics Letters, Section A: General, Atomic and Solid State Physics
Volume236
Issue number3
DOIs
Publication statusPublished - 8 Dec 1997
Externally publishedYes

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kinetics
Reynolds number
statistics
energy

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Flow helicity in a simplified statistical model of a fast dynamo. / Kim, Eun Jin; Hughes, David W.

In: Physics Letters, Section A: General, Atomic and Solid State Physics, Vol. 236, No. 3, 08.12.1997, p. 211-218.

Research output: Contribution to journalArticle

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