Voltage-current characteristics of subsonic disk CCMHD generator

Voltage-current characteristics of a subsonic disk CCMHD generator are examined by time-dependent quasi-one-dimensional numerical simulations. The output voltage is found to be almost constant for load resistances higher than the designed value, whereas the output current is kept almost constant for lower load resistances. It is confirmed that at high load resistances the subsonic flow is maintained in the whole generator, and a steady and uniform nonequilibrium plasma is realized. The connection of the low load resistances causes flow choking at the generator inlet, leading to the supersonic flow. Then shock waves and ionization instability occur in the generator.