Plasma model of discharge along a dielectric surface in N2/O2 mixtures

Surface discharge phenomena often occur across the insulator in power systems, damaging the electrical equipment, but the mechanism of the electron multiplication stage during surface discharge is not yet fully understood. As such, it is necessary to investigate the mechanism of discharge along a dielectric surface. In this paper, we develop a numerical fluid model, analyzing the dynamic characteristics of discharge including the electron density, electron temperature, surface charge density, and electric field. Our results show that the electron density peaks in the head of the streamer channel, at which time the electron temperature also reaches its maximum. A thin layer of plasma can be formed, filled with a mix of positive and negative charges, so the space normal electric field in the streamer channel can be positive or negative. In addition, the surface tangential electric field and electric potential are closely related, and the potential steadily increases because there is a steady tangential electric field in the streamer channel. Published by AIP Publishing.