Analysis of Electron Temperature and Heavy Particle Temperature at Vacuum Arc Cathode Spot as a Function of Ambient Pressure

The vacuum arc cathode spot is characterized by a fast-moving electron emission spot with a high current density and low voltage. The factors that cause the movement of the vacuum arc cathode spot have not yet been elucidated, and simulations based on the assumption of local thermal equilibrium have been performed in previous research. However, since the non-equilibrium between electrons and heavy particles is remarkable in high vacuum discharges, it is necessary to consider the spatial and thermal non-equilibrium between electrons and heavy particles in order to elucidate the movement factor of the cathode spot. In this calculation, thermal non-equilibrium is considered by solving the conservation of energy equations for electrons and heavy particles, respectively. In this research, electron temperature and heavy particle temperature at vacuum arc cathode spot as a function of ambient pressure was analyzed by three-dimensional electromagnetic thermal fluid simulation with consideration of thermal non-equilibrium.