Instabilities of rotational flows in azimuthal magnetic fields of arbitrary radial dependence
Solar and Stellar Astrophysics
2014-05-29 v2 Dynamical Systems
Fluid Dynamics
Plasma Physics
Abstract
Using the WKB approximation we perform a linear stability analysis for a rotational flow of a viscous and electrically conducting fluid in an external azimuthal magnetic field that has an arbitrary radial profile B_{phi}(R). In the inductionless approximation, we find the growth rate of the three-dimensional perturbation in a closed form and demonstrate in particular that it can be positive when the velocity profile is Keplerian and the magnetic field profile is slightly shallower than R^{-1}.
Keywords
Cite
@article{arxiv.1307.1576,
title = {Instabilities of rotational flows in azimuthal magnetic fields of arbitrary radial dependence},
author = {Oleg N. Kirillov and Frank Stefani and Yasuhide Fukumoto},
journal= {arXiv preprint arXiv:1307.1576},
year = {2014}
}
Comments
15 pages, 2 figures, slightly extended, the case of finite Rm treated, results were partially presented at the IUTAM Symposium on Vortex Dynamics, Fukuoka, Japan, March 10 2013