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A theory of MHD instability of an inhomogeneous plasma jet

Published online by Cambridge University Press:  23 July 2010

ANATOLY S. LEONOVICH
ANATOLY S. LEONOVICH*
Affiliation:
Institute of Solar-Terrestrial Physics (ISTP), Russian Academy of Science, Siberian Branch, Irkutsk 33, P.O. Box 4026, 664033, Russia ([email protected])
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Abstract

A problem of the stability of an inhomogeneous axisymmetric plasma jet in a parallel magnetic field is solved. The jet boundary becomes, under certain conditions, unstable relative to magnetosonic oscillations (Kelvin–Helmholtz instability) in the presence of a shear flow at the jet boundary. Because of its internal inhomogeneity the plasma jet has resonance surfaces, where conversion takes place between various modes of plasma magnetohydrodynamic (MHD) oscillations. Propagating in inhomogeneous plasma, fast magnetosonic waves drive the Alfven and slow magnetosonic (SMS) oscillations, tightly localized across the magnetic shells, on the resonance surfaces. MHD oscillation energy is absorbed in the neighbourhood of these resonance surfaces. The resonance surfaces disappear for the eigenmodes of SMS waves propagating in the jet waveguide. The stability of the plasma MHD flow is determined by competition between the mechanisms of shear flow instability on the boundary and wave energy dissipation because of resonant MHD-mode coupling. The problem is solved analytically, in the Wentzel, Kramers, Brillouin (WKB) approximation, for the plasma jet with a boundary in the form of a tangential discontinuity over the radial coordinate. The Kelvin–Helmholtz instability develops if plasma flow velocity in the jet exceeds the maximum Alfven speed at the boundary. The stability of the plasma jet with a smooth boundary layer is investigated numerically for the basic modes of MHD oscillations, to which the WKB approximation is inapplicable. A new 'unstable mode of MHD oscillations has been discovered which, unlike the Kelvin–Helmholtz instability, exists for any, however weak, plasma flow velocities.

Type
Papers
Information
Journal of Plasma Physics , Volume 77 , Issue 3 , June 2011 , pp. 315 - 337
Copyright
Copyright © Cambridge University Press 2010

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References

Azovsky, , Yu, C., Guzhovsky, I. T. and Pistryak, V. M. 1967 In: Investigations of a Plasma Clusters (in Russian). Kiev: Naukova Dumka, pp. 56–65.Google Scholar
Chen, L. and Hasegawa, A. 1974 Phys. Fluids 17, 1399.Google Scholar
Drazin, P. G. and Howard, L. N. 1966 Adv. Appl. Mech. 9, 1–89.CrossRefGoogle Scholar
Erdelyi, R. 2004 Astron. Geophys. 45, 4.34.CrossRefGoogle Scholar
Filippov, B, Golub, L. and Koutchmy, S. 2009 Solar Phys. 254, 259–269.CrossRefGoogle Scholar
Fujita, S., Glassmeier, K. H. and Kamide, K. 1996 J. Geophys. Res. 101, 27317–27326.CrossRefGoogle Scholar
Kivelson, M. G. and Pu, Z-Y. 1984 Planet. Space Sci. 32, 1335.CrossRefGoogle Scholar
Landau, L. D. 1944 Akad. Nauk S.S.S.R., Compts Rendus (Doklady) 44, 139–142.Google Scholar
Leonovich, A. S. and Kozlov, D. A. 2009 Plasma Phys. Control. Fus. 51, 085007.CrossRefGoogle Scholar
Lukiyanov, , 1975 Hot Plasma and Controlled Fusion (in Russian). Moskow: Nauka, p. 407.Google Scholar
McKenzie, J. F. 1970a Planet. Space Sci. 18, 1.CrossRefGoogle Scholar
McKenzie, J. F. 1970b J. Geophys. Res. 75, 5331–5339.Google Scholar
Miura, A. 1992 J. Geophys. Res. 97, 10655–10675.CrossRefGoogle Scholar
Perkins, W. A. and Post, R. F. 1963 Phys. Fluids, 6, 1537–1558.CrossRefGoogle Scholar
Rosenbluth, M. N. and Longmire, C. L. 1957 Ann. Phys. 1, 120–140.CrossRefGoogle Scholar
Thorpe, S. A. 1969 J. Fluid Mech. 36, 673–683CrossRefGoogle Scholar
Watson, M. 1981 Geophys. Astrophys. Fluid Dyn. 16, 285–298.CrossRefGoogle Scholar