Plasma Fluctuations in a Flow Field with a Steep Increase in Static Pressure in a Closed Cycle Disk MHD Generator.

Abstract

Plasma fluctuations in a flow field with a steep increase in static pressure in a closed cycle disk magnetohydrodynamic (MHD) generator, caused by varying the pressure at the channel exit, were examined by means of a quasi-one-dimensional numerical simulation. In order to compute the plasma properties at the exit boundary for subsonic flow, the characteristic theory where the effects of the MHD interaction are taken into account was developed. The computational results indicated that the fluctuations of the gas dynamic and electrical properties propagated upstream at a speed of sound relative to the local plasma flow velocity. The time variation of the output Hall voltage due to the application of pressure pulse decreased with time and, finally, the Hall voltage reached almost the same level as that for the steady-state.