Amplification of magnetovortex waves in planar MHD flows

The propagation of magnetovortex waves in an inhomogeneous medium with planar flow and perpendicular magnetic field is investigated. The linearized MHD equations are studied with the aid of the WKB approximation. Within the latter, a set of ordinary differential equations along the streamlines of the basic flow is derived. These equations govern the variations of the transverse as well as the parallel magnetovortex waves along its rays. The amplitude equations are solved explicitly for a particular geometry of the basic flow, and the solutions are investigated for subsonic as well as for supersonic basic flows.