Influence of electron density and gas temperature on the streamer discharge process of air spark switch

In this paper, a two-dimensional fluid-chemical reaction hybrid model of air spark switch is established and its micro-process in streamer discharge is analyzed. The air switch adopts the two electrodes of rod-rod ball-head structure with a gap distance of 3 mm. The transient physical parameters such as electron density, electric field, and discharge current were obtained, and the different breakdown time delays of streamer discharge have been presented and analyzed under the action of a single memory effect factor (electron density or gas temperature) and two memory effect factors jointly. It is shown that the generation, propagation, and connection processes of streamers, as well as its propagation speed, are consistent with the model in existing literature studies. The discharge process can be divided into corona, streamer, and streamer to spark transition stage according to the simulated current waveform. Nonlinear surface functions of breakdown time delay and average electric field intensity under the combined action of two memory effect factors are proposed. The work performed in this paper might provide theoretical guidance for the influence of memory effect on the streamer discharge process of gas switch.