Cathode spots on metallic electrodes under the conditions of the channel of a MHD generator

The article discusses cathode processes of an arc discharge under the conditions of the channel of an MHD generator, a special characteristic of which is the deposition of a layer of additive on the surface of the metallic electrode. It gives a theoretical description of the above kind of discharge, in accordance with which a spot burns as the result of the vaporization of a previously deposited film of additive, while the temperature of the spot is determined by the thermal conductivity of the metallic cathode. For a copper cathode, the article gives calculations of the radius and the temperature of the spots as a function of the mean temperature of the surface of the electrode.