Modeling of a nonequilibrium cylindrical column of a low-current arc discharge

Numerical modeling of a wall-stabilized low-current are discharge in the hi gh pressure argon plasma is performed with account both of a deviation of t he electron temperature from the heavy-particle temperature and of a deviat ion from the ionization equilibrium, Results are presented for a current ra nge from currents of the order of 100 A down to several A, in which a regim e of the discharge varies from the one typical for an are discharge (local thermodynamic equilibrium (LTE) in the hot core, energy supplied to electro ns by the electric field is mainly removed by the electron heat conduction) to the one typical fur a glow discharge. (The electron temperature is subs tantially higher than the heavy-particle temperature and does not change mu ch across the column, the ionization exceeds or substantially exceeds the r ecombination in every point of the column, energy supplied to electrons by the electric held is mainly locally transferred to heavy particles). On the axis of the discharge, the deviations from LTE become appreciable when the current decreases to several tens A. The deviation from the ionization equ ilibrium comes into play at higher currents than the deviation from the the rmal equilibrium. Comparison with available experimental data is given.