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arXiv · 0906.5383

Three-dimensional evolution of magnetic and velocity shear driven instabilities in a compressible magnetized jet

Lapo Bettarini·Simone Landi·Marco Velli·Pasquale Londrillo
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Abstract

The problem of three-dimensional combined magnetic and velocity shear driven instabilities of a compressible magnetized jet modeled with a plane neutral/current double vortex sheet in the framework of the resistive magnetohydrodynamics is addressed. The resulting dynamics given by the stream+current sheet interaction is analyzed and the effects of a variable geometry of the basic fields are considered. Depending on the basic asymptotic magnetic field configuration, a selection rule of the linear instability modes can be obtained. Hence, the system follows a two-stage path developing either through a fully three-dimensional dynamics with a rapid evolution of kink modes leading to a final turbulent state, or rather through a driving two-dimensional instability pattern that develops on parallel planes on which a reconnection+coalescence process takes place.

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Lapo Bettarini, Simone Landi, Marco Velli, Pasquale Londrillo. 2009-06-29. Three-dimensional evolution of magnetic and velocity shear driven instabilities in a compressible magnetized jet. https://doi.org/10.1063/1.3142467

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