TY - JOUR

T1 - Self-consistent theory of mean-field electrodynamics

AU - Gruzinov, A. V.

AU - Diamond, P. H.

N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.

PY - 1994

Y1 - 1994

N2 - 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.

AB - 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.

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U2 - 10.1103/PhysRevLett.72.1651

DO - 10.1103/PhysRevLett.72.1651

M3 - Article

AN - SCOPUS:0000169630

SN - 0031-9007

VL - 72

SP - 1651

EP - 1653

JO - Physical Review Letters

JF - Physical Review Letters

IS - 11

ER -