Positive Pulsed Streamer in Supercritical Carbon Dioxide

Abstract

A positive pulsed streamer in a needle-to-plane gap in supercritical carbon dioxide was observed by using a laser schlieren method. The treelike streamer is initiated at a needle electrode when the electric field reaches approximately 9 MV/cm and propagates spatially toward a plane electrode. The streamer is accompanied by the cylindrical and spherical shock waves. A low-density region along the streamer channel decays with time, and no bubble formation occurs finally.