MHD Dynamos and Turbulence

doi:10.1017/CBO9781139032810.010

9 - MHD Dynamos and Turbulence

Published online by Cambridge University Press: 05 February 2013

S.M. Tobias ,

F. Cattaneo and

S. Boldyrev

Edited by

Peter A. Davidson ,

Yukio Kaneda and

Katepalli R. Sreenivasan

Show author details

S.M. Tobias: Affiliation:
University of Leeds
F. Cattaneo: Affiliation:
University of Chicago
S. Boldyrev: Affiliation:
University of Wisconsin – Madison
Peter A. Davidson: Affiliation:
University of Cambridge
Yukio Kaneda: Affiliation:
Aichi Institute of Technology, Japan
Katepalli R. Sreenivasan: Affiliation:
New York University

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Summary

Introduction

Magnetic fields are ubiquitous in the universe (Parker (1979); Zeldovich et al. (1983)). Their interaction with an electrically conducting fluid gives rise to a complex system–a magnetofluid-whose dynamics is quite distinct from that of either a non conducting fluid, or that of a magnetic field in a vacuum (Cowling (1976)). The scales of these interactions vary in nature from metres to megaparsecs and in most situations, the dissipative processes occur on small enough scales that the resulting flows are turbulent. The purpose of this review is to discuss a small fraction of what is currently known about the properties of these turbulent flows. We refer the reader to several recent reviews for a broader view of the field (Biskamp (2003); Galtier (2008, 2009); Lazarian (2006); Lazarian & Cho (2005); Müller & Busse (2007); Kulsrud & Zweibel (2008), Bigot et al. 2008, Sridhar 2010, Brandenburg & Nordlund 2010). The electrically conducting fluid most commonly found in nature is ionized gas, i.e. a plasma, and its description in terms of all its fundamental constituents is extremely complex (see e.g. Kulsrud (2005)). In many circumstances, however, these complexities can be neglected in favour of a simplified description in term of a single fluid interacting with a magnetic field. Formally, this approach is justifiable when the processes of interest occur on timescales long compared with the light-crossing time, and on spatial scales much larger that any characteristic plasma length.

Type: Chapter
Information: Ten Chapters in Turbulence , pp. 351 - 404

DOI: https://doi.org/10.1017/CBO9781139032810.010 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2012

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