Velocity of initial propagation of positive nanosecond discharge in liquid water: dependence on high voltage amplitude and water conductivity

0509789 - ÚFP 2020 RIV GB eng J - Článek v odborném periodiku
Pongrác, Branislav - Šimek, Milan - Ondáč, Peter - Člupek, Martin - Babický, Václav - Lukeš, Petr
Velocity of initial propagation of positive nanosecond discharge in liquid water: dependence on high voltage amplitude and water conductivity.
Plasma Sources Science & Technology. Roč. 28, č. 2 (2019), č. článku 02LT02. ISSN 0963-0252. E-ISSN 1361-6595
Grant CEP: GA ČR(CZ) GA18-04676S; GA ČR(CZ) GA15-12987S
Institucionální podpora: RVO:61389021
Klíčová slova: underwater discharge * nanosecond pulsed discharge * time-resolved ICCD imaging
Obor OECD: Fluids and plasma physics (including surface physics)
Impakt faktor: 3.193, rok: 2019
Způsob publikování: Omezený přístup
https://iopscience.iop.org/article/10.1088/1361-6595/aae91f

This study deals with the effect of water conductivity and high voltage pulse amplitude on the initial velocity of nanosecond discharge in liquid water. As variable parameters, we used water solutions with three different conductivities (2 mu S cm(-1), 100 mu S cm(-1), 500 mu S cm(-1)), and positive high voltage pulses with four different amplitudes (80 kV, 91 kV, 100 kV, 113 kV). The discharge reactor consists of metallic electrodes in a point-to-plane geometry, both immersed in liquid water. The discharge was generated by a commercial nanosecond pulse power generator with positive HV pulses of similar to 6 ns pulse duration (FWHM) and similar to 2.5 ns rise time. ICCD time-resolved imaging microscopy with high temporal resolution (similar to ns) was utilized as a suitable diagnostic tool for the discharge dynamic propagation. It can be concluded that the discharge visual characteristics and behaviour are not significantly influenced by water conductivity and the length of the filaments increases with the increasing voltage amplitude and reaches the maximum value of similar to 1.8 mm for 90 kV. The initial propagation velocity also depends on the voltage amplitude and increases with the voltage. The effect of water conductivity on the propagation velocity is negligible. As far as we know, this paper is the first to bring insight into the topic of the effect of water conductivity on the nanosecond discharge propagation in liquid water.
Trvalý link: http://hdl.handle.net/11104/0300415