A New Nonlinear Mean-Field Dynamo Theory and Closure Approach

Preprint

22 July 2002

preprint
Published by arXiv in arXiv

Abstract

We develop a nonlinear mean field dynamo and closure approach that couples field growth to the time evolution of both magnetic helicity and the turbulent electromotive force. The difference between small-scale kinetic and current helicities emerges as the growth driver, whilst the kinetic and magnetic energy density difference plays a role in turbulent diffusion. The saturation rate/strength is magnetic Reynolds number dependent/independent, in agreement with numerical simulations. A significant kinematic growth phase and early-time oscillations are also discussed.

Keywords

NUMERICAL SIMULATIONS
NONLINEAR MEAN FIELD
MEAN FIELD DYNAMO
CLOSURE APPROACH
REYNOLDS NUMBER
TURBULENT
KINETIC
GROWTH

All Related Versions

Version 1, 2002-07-22, ArXiv
Version 2, 2002-07-22, ArXiv
Version 3, 2002-10-23, ArXiv
Published version: Physical Review Letters, 89 (26), 265007.

This publication has 0 references indexed in Scilit: