Gas Heating and Formation of Single Liner Discharge Channel on Repetitive Branched Streamer Corona

Abstract

Under non-uniform field in atmospheric short-gap, the branched pulse streamer corona changes to single liner discharge channel (SLDC) for a split second just before sparkover occurs. This SLDC is pre-transitional phenomenon of sparkover. Therefore, it is very important to study SLDC for understanding sparkover process. In this work, the SLDC was recreated well by applying highly repetitive impulse voltage to needle to plane gap in synthetic air with dilute CO₂. The characteristics of SLDC including the channel temperature, the propagation of streamer head and the formation process were revealed by means of ICCD cameras and a spectroscopic measurement system.