Modeling of the electrogun metal vapor plasma discharge

The electrogun metal vapor plasma discharge is a new high-power pulsed device for producing vapors of different metals, The process employs electrode erosion to vaporize one of the discharge electrodes. The eroded metal vapor is subsequently ionized to form a dense plasma in which a high current discharge is sustained. The vapor plasma then exits the discharge where it can be used in the synthesis of novel materials or as an ignitor for electrothermal-chemical guns. A model for the electrogun discharge bore plasma how bore wall erosion, and simplified models for the cathode and anode regions are presented in this paper. The bore plasma flows under local thermodynamic equilibrium conditions and is weakly nonideal. Two electrogun shots involving different cathode materials (aluminum and titanium) are simulated. Results reveal the physics underlying the operation of the electrogun discharge. High pressures of the bore plasma result in thermal choking at bore exit. Cathode material erosion dominates over the bore wall erosion, thus ensuring a relatively pure metal vapor yield. The exit parameters of the electrogun are predicted and can be used as input boundary conditions for analysis of the external plasma jet flow.