Simulation of high current vacuum arc with hybrid cathode attachment

Abstract

A model of the hybrid cathode attachment of a high-current vacuum arc with a characteristic average current density at the cathode of 105–106 A/cm2, in which multiple rapidly moving cathode spots and a quasi-stationary thermal spot coexist, is proposed. The numerical simulation of the formation and expansion of a plasma jet with a hybrid cathode attachment showed that the model can explain the sharp increase in the mass of the plasma jet and cathode erosion observed in experiments on magnetic implosion. Characteristic evidence for the onset of hybrid cathode attachment is predicted and can be verified experimentally.