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Nonlinear Dynamos

Published online by Cambridge University Press:  12 August 2011

David Galloway
David Galloway*
Affiliation:
School of Mathematics and Statistics, University of Sydney, NSW 2006, Australia email: [email protected]
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Abstract

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This paper discusses nonlinear dynamos where the nonlinearity arises directly via the Lorentz force in the Navier-Stokes equation, and leads to a situation where the Lorentz force and the velocity and the magnetic field are in direct competition over substantial regions of the flow domain. Filamentary and non-filamentary dynamos are contrasted, and the concept of Alfvénic dynamos with almost equal magnetic and kinetic energies is reviewed via examples. So far these remain in the category of toy models; the paper concludes with a discussion of whether similar dynamos are likely to exist in astrophysical objects, and whether they can model the solar cycle.

Keywords

magnetic fieldsMHDSun: magnetic fieldsstars: magnetic fields
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 6 , Symposium S271: Astrophysical Dynamics: From Stars to Galaxies , June 2010 , pp. 297 - 303
Copyright
Copyright © International Astronomical Union 2011

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