Self-consistent theory of mean-field electrodynamics

A. V. Gruzinov, P. H. Diamond

    Research output: Contribution to journalArticle

    Abstract

    Mean-field electrodynamics, including both α and β effects while accounting for the effects of small-scale magnetic fields, is derived for incompressible magnetohydrodynamics. The principal result is α=(α0+β0R×R)/(1+R2), β=β0; where α0,β0 are conventional kinematic dynamo parameters, the reduction factor is proportional to the mean magnetic field R=Rm1/2B/(ρV2)1/2, Rm is the magnetic Reynolds number, and V is the characteristic turbulent velocity. This result follows from a generalization of the Zeldovich theorem to three dimensions, exploiting magnetic helicity balance.

    Original languageEnglish (US)
    Pages (from-to)1651-1653
    Number of pages3
    JournalPhysical Review Letters
    Volume72
    Issue number11
    DOIs
    StatePublished - 1994

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    electrodynamics
    magnetic fields
    magnetohydrodynamics
    Reynolds number
    kinematics
    theorems

    ASJC Scopus subject areas

    • Physics and Astronomy(all)

    Cite this

    Self-consistent theory of mean-field electrodynamics. / Gruzinov, A. V.; Diamond, P. H.

    In: Physical Review Letters, Vol. 72, No. 11, 1994, p. 1651-1653.

    Research output: Contribution to journalArticle

    Gruzinov, A. V. ; Diamond, P. H. / Self-consistent theory of mean-field electrodynamics. In: Physical Review Letters. 1994 ; Vol. 72, No. 11. pp. 1651-1653.
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