Two-Dimensional Simulation of Hydrogen Direct-Current Discharge Plasma

A two-dimensional model of a weakly-ionized hydrogen direct-current (DC) discharge at low pressure is simulated. In the model, the metal electron overflow and secondary electron emission coefficient at the cathode spot are introduced to represent the relationship between the electron and ion density, and the electron energy distribution function is expressed by kinetic theory. The electron current density and reaction constant reasonably set on the boundary are discussed. In addition, it is determined that 11 collision reactions play a major role in low pressure and weakly ionized hydrogen discharges. On this basis, the relationship between mobility, electrode spacing, and breakdown voltage is verified. Good agreement is achieved between the simulation curve and Paschen curve.