Stability of magnetohydrodynamic shear flows with and without bounding walls
Abstract
We have solved the shear flow stability problem of compressible electrically conducting fluid (plasma) in a magnetic field. A comparative analysis is made of the influence of different boundary conditions on shear flow stability. We consider the problems for flows in an unbounded medium and a flow between fixed walls, as well as in the presence of a fixed wall on one side of the shear flow only. Shear flow velocity profiles are treated both in the form of a tangential discontinuity and as being described by a hyperbolic tangent function. For the case of an unbounded flow with a velocity vortex sheet, analytical solutions are found; for all other cases, the solutions are found numerically. Problems are solved for two different positions of the tangential wave vector of oscillations and magnetic field k_t {⊥} B_0 and k_t {parallel} B_0. For shear flows bounded by a fixed wall we found an unstable mode of oscillations produced by the wave, reflected from the wall and transmitted through the shear layer.
- Publication:
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Journal of Plasma Physics
- Pub Date:
- October 2005
- DOI:
- Bibcode:
- 2005JPlPh..71..645L