1995 Volume 115 Issue 9 Pages 1098-1103
In closed cycle MHD power generation, the realization of uniform plasma in whole channel is needed in order to achieve high generator performance. The disk generator used in experiments should have the wide allowable operation range as well as the high maximum enthalpy extraction ratio, for the purpose of the successful power generation experiments. Therefore, the stability of operation of disk MHD generators driven by cesium seeded argon working gas is investigated by means of the linear and nonlinear theories of ionization instability. For the experimental generator whose height changes straightly along the disk radius, such as disk type generators installed in FUJI-1 facility, too large area ratio of outlet to inlet makes the region of acceptable operation conditions narrow. The near-ideal experimental generator which have the wide region of operation conditions providing high enthalpy extraction ratio is proposed by modifying the channel shape of a disk generator installed in FUJI-1 facility. It is found from the discussions of enthalpy extraction ratio of the proposed generator that the electron temperature at the inlet must be kept around 5000K.