2-DIMENSIONAL MODEL OF GLOW-DISCHARGES FOR A CYLINDRICAL GEOMETRY

A computer simulation of a dc glow discharge is presented. The simulation consists of a two-dimensional continuum model for electron and ion transport using the local field approximation. The continuity equations of electron and ion are coupled with Poisson's equation for a given set of boundary conditions. Potential values on insulator are determined by taking surface charges on it into account. Numerical calculations were made for 1 Torr helium glow discharges in a cylindrical discharge vessel with an electrode on each end. The current density I(c) ranged from 1 to 40-mu-A/cm2. The voltage-current curve has a minimum voltage at about I(c) = 4-mu-A/cm2. At higher values of I(c), a typical character of glow discharge was realized; peak ion density in front of the cathode and charge-neutrality region in front of the anode.