Continuous Visualization of Process of Positive Streamer Initiation, Propagation, Spark, and Bubble Expansion in Water

Electrical discharge in liquids is a phenomenon which is seen in dielectric breakdown of insulating oils used in transformers and liquids for electric discharge machining, and has been investigated in many studies. Although this technique has also been applied to water purification and the medical field in recent years, how the discharge propagates in the liquid, which is fundamental to these applications, still has not been elucidated.
In this application, the phenomenon called streamers that occurs prior to discharge is visualized, and the condition of propagation is explained.