Theoretical study of plasma expansion and electrical characteristics in the high-current vacuum arc

The high-current vacuum arc plasma expansion is investigated using a two-dimensional model. The model considers the free boundary of the plasma jet, which is determined by a self-consistent solution of the gas-dynamic and electrical current equations. The electron temperature distribution is calculated from energy conservation. An influence of the starting condition at the cathode side (electron temperatures and directed velocity) on the interelectrode plasma parameter distribution is studied. It was found that the high current constriction leads to plasma compression, which accompanied by electron temperature grow. Plasma jet mixing leads to decrease of the directed plasma jet velocity that in turn affect potential distribution in the interelectrode gap