Statistical Study of Branching Angles of Streamer Discharges on a Liquid Surface

Atmospheric-pressure streamer discharges on the surface of water have been experimentally studied at two different voltage polarities on a high-voltage electrode. Photorecording of the discharge structure and statistical analysis of the resulting images have been carried out. It has been found that the streamers have a complex structure with many branching channels. The number of branches in negative streamers turned out to be several times greater than the number of branches of positive streamers, with the average branching angle in positive discharges being greater than that in discharges of negative polarity. Neither branches with angles >90° nor intersection points of different branches have been revealed.