Experiments on plasma-physical aspects of closed cycle MHD power generation

In this paper, important laboratory experiments in closed-cycle magneto-hydrodynamic (MHD) generator plasmas are discussed. The following aspects are treated: electron temperature elevation and nonequilibrium ionization, fluctuations and nonuniformity, streamers as the nonlinear appearance of ionization instability, inlet relaxation, and fully ionized seed as a concept to suppress ionization instability. Conclusions are presented on electrical transport parameters in nonuniform plasmas, streamer fine structure, streamer velocity, streamer initiation in relation to inlet relaxation, and the fully ionized seed concept.