Time-resolved processes in a pulsed electrical discharge in plate-to-plate configuration

0477118 - ÚFP 2018 CZ eng A - Abstrakt
Stelmashuk, Vitaliy
Time-resolved processes in a pulsed electrical discharge in plate-to-plate configuration.
Internetional Conference on Plasmas with Liquids (ICPL 2017). Prague: Institute of Plasma Physics Academy of Sciences, 2017. s. 46. ISBN 978-80-87026-6.
[Internetional Conference on Plasmas with Liquids (ICPL 2017). 05.03.2017-09.03.2017, Prague]
Institucionální podpora: RVO:61389021
Klíčová slova: Discharge in water * plate electrodes * streamer
Obor OECD: Fluids and plasma physics (including surface physics)

Plasma processes involving liquid phases are widely used in various applications, such as biomedical processes, shock wave generation for medical applications, material processes, sterilization in water treatment and others. Two main configurations of high voltage electrodes submersed in water have been used for an electrical discharge generation: pin˗to˗pin and pin˗to˗plate. An electrical breakdown in the plate˗to˗plate configuration is generally difficult to reproduce, because there is a uniform and weak electric field in the interelectrode region in this geometry. One major advantage of using plate electrodes is their greater “wear hardness” to high-energy discharges. The plate electrodes can withstand extremely high energy deposition at which the pin electrode is quickly destroyed. Due to that the system of plate electrodes is proposed to be used for shock wave generation in litotripsy. The electrical discharge between plate electrodes can be initiated by creating an inhomogeneity in the electrical field. Two methods of discharge initiation between plate electrodes are proposed for this aim: 1) focusing of a shock wave in the interelectrode region; 2) a bubble injection into the electrode gap. Both methods employ the fact that a typical order of magnitude of an electrical breakdown field for gas is 30 kV cm−1 , i.e. 30 times less than the electrical field required for the electrical breakdown in water. The physical mechanisms of discharge initiation and positive streamer propagation are discussed.
Trvalý link: http://hdl.handle.net/11104/0273509