Ionization Relaxation Region in a Nonequilibrium Disk MHD Generator

The ionization relaxation region in an Ar/K-driven disk MHD generator and its effects have been experimentally investigated. Experimental results have shown that a decrease in the stagnation temperature of a working gas increases the area covered by the negative Hall field near the anode, which is strongly affected by ionization relaxation, and results in reducing output power. It is also observed that the power output increases with an increase in seed fraction. The unfavorable effects of ionization relaxation can be reduced by increasing applied magnetic field strength. Comparison between the results of one-dimension al calculations and experimental results has also been performed. Calculations can predict the Hall potential distribution along the flow direction when we assume an adequate electron temperature at the MHD channel inlet and fluctuations of a plasma at the inlet of the channel are assumed to be insignificant.