Kinetic Model of Short Vacuum Arc With Hot Evaporating Anode

A kinetic 1-D model of an ultrashort (10 $\mu\hbox {m}$ ) vacuum arc was developed to research the vacuum arc near-anode region and the influence of anode plasma on the cathode attachment self-consistently. The kinetic model is a model of 1D3V particle-in-cell and direct simulation Monte Carlo type. The model takes into account the main types of elastic and inelastic collisions of particles in the plasma as well as evaporation and thermofield electron emission from both of the electrodes. The model has three task parameters: cathode temperature, anode temperature, and voltage drop applied to the gap. The plasma state in the gap, current density, and energy flux density to the electrodes are the outcome of the model. The calculations have shown that the anode temperature variation strongly influences both the plasma column parameters and the cathode attachment. It was shown that, at the ratio $T_{a}/T_{c} \sim 1$ (with $T_{a}$ and $T_{c}$ being the anode and cathode temperatures, respectively), the plasma in the gap changes the direction of motion.