ELECTRODE PHENOMENA IN SLAGGING MHD CHANNELS.

A theoretical and experimental study of electrode phenomena, as they relate in particular to the interfacial current transport in slagging MHD channels, is presented. The theoretical study includes an analysis of the stability of the current transport in the vicinity of electrode walls. Generator studies of the current transport process include voltage drop measurements and visual studies of the current transport to anodes and cathodes. The effect of slag and of the magnetic field are discussed. The experimental study is complemented by an evaluation of the degradation characteristics of various anode and cathode materials and designs. Degradation characteristics are compared both with and without slag. Some insulator material, temperature and design selection problems are also discussed. Long duration MHD channel tests indicate that massive, low temperature metallic current collectors of sufficient thermal diffusivity can operate as cathodes in the arcing regime without any appreciable degradation, with and without slag (time scale approximately equals 40 hrs).