Self-consistent mean field electrodynamics of turbulent dynamos
- 1 June 1995
- journal article
- research article
- Published by AIP Publishing in Physics of Plasmas
- Vol. 2 (6) , 1941-1946
- https://doi.org/10.1063/1.871495
Abstract
A turbulent dynamo in a conducting fluid is accompanied by the generation of small‐scale magnetic fields, which are much stronger than the mean dynamo‐generated magnetic field. These small‐scale fields modify the α effect in such a way as to stabilize the dynamo process, α=(α0+β0R⋅/B∇× R)/(1+R2), where α0, β0 are the standard kinematic dynamo parameters, and R is proportional to the mean magnetic field B0, R=B0/(4πρV2/Rm)1/2, ρ is the fluid density, V is the characteristic turbulent velocity, and Rm is the magnetic Reynolds number. The derivation of this formula is illustrated using a simple model—the turbulent dynamo for an asymmetrical top.Keywords
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