Kinetic model of short vacuum arc with active anode

Abstract

A kinetic one-dimensional model of ultra short (10 microns) vacuum arc was developed to research the vacuum arc near-anode region and the influence of anode plasma on the cathode attachment selfconsistently. The kinetic model is a model of 1D3V PIC/DSMC type. The model takes into account the main types of elastic and inelastic collisions of particles in the plasma as well as evaporation and thermo-field electron emission from the both 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 fluxes 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 ∼ 1 (T a , T c -anode and cathode temperature) the plasma in the gap changes the direction of motion, so the conventional arc transits to the anodic arc.