Computer modeling of interaction of gas discharge plasma with solid dielectric barriers

A computer model describing charge transfer in a system consisting of two parallel-plate metallic electrodes covered with solid dielectric barriers immersed in gas medium is proposed. The material of the barriers is supposed to be a non-ideal insulator whose properties correspond to polyethylene and air is considered as a gas phase. The model is based on continuity equations for fluxes of charge carriers and accounts for their drift and diffusion and also for different sources of their generation and losses in different media. The continuity equations are coupled with Poisson´s equation for computing electric fields affected by temporal and spatial variations of space charges in the system. Results of the computer simulations are obtained for the case when the applied field in the gas exceeds its breakdown threshold, i.e. charge transfer in the gas phase takes place in the form of an electrical discharge (electron avalanche and streamer). Evolution of generated discharge plasma is analyzed taking into account conditions on gas-solid interfaces and in the bulk of the solid dielectric barriers.