Breakdown characteristics of spark discharge on water surface (SDWS) with an air gap

Electrical discharge on water surface is widely being investigated for various applications in environmental and industrial fields. Besides that, it is also being investigated to understand the mechanism of lightning phenomena that occurred on water surface. However, the fundamental characteristics of this type of discharge are still unknown. In the previous report 2011 CEIDP, the discharge current distribution due to spark discharge on water surface with air gap of a point-to-plane electrode system was investigated. The results indicate that the discharge current distribution characteristics show a significant difference between tap water and saline solutions. Thus, it is necessary to find an explanation regarding the difference that was observed. In this work, the breakdown characteristic during spark discharge on water surface with different conductivity of the same electrode configuration was investigated. In the experiment, the input voltage and current waveforms during the discharge was observed using an oscilloscope and a current probe. Besides that, the discharge profile was also observed using a camera. The results will be discussed in V-I characteristics of the breakdown and occurrence of filamentary discharge on water surface. In addition, the influence of water conductivity towards the breakdown characteristics and filamentary discharge is discussed.