Characterization of novel pin-hole based plasma source for generation of discharge in liquids supplied by DC non-pulsing voltage

Characterization of novel pin-hole based plasma source for generation of discharge in liquids supplied by DC non-pulsing voltage

WoS Article

A recently presented novel plasma source generating discharge in liquids based on the pin-hole discharge configuration is characterized in detail. The system is supplied by DC non-pulsing high voltage of both polarities in NaCl water solutions at a conductivity range of 100-15 000 mu S/cm. The discharge itself shows self-pulsing operation. The discharge ignition is observed in micro bubbles by transient discharge followed by a glow discharge in positive polarity at lower conductivities propagating inside the bubbles. At high conductivities, the glow regime is particularly replaced by a more energetic sequence of transient discharges followed by a shorter glow mode operation. The transient regime probability and its intensity are higher in the negative discharge polarity. The transient discharge produces acoustic waves and shock waves, which are observed at the moment of the bubble cavitation. The average gas temperature of 700-1500 K was calculated from the lowest OH (A-X) 0-0 band transitions. The average electron concentrations of 10(20)-10(23) m(-3) were calculated from H alpha and H beta line profiles. Finally, the production of a chemically active species is determined by hydrogen peroxide energy yields related to the energy consumption of the whole interelectrode system. All these quantities are dependent on the solution conductivity, the discharge polarity, and the applied power

A recently presented novel plasma source generating discharge in liquids based on the pin-hole discharge configuration is characterized in detail. The system is supplied by DC non-pulsing high voltage of both polarities in NaCl water solutions at a conductivity range of 100-15 000 mu S/cm. The discharge itself shows self-pulsing operation. The discharge ignition is observed in micro bubbles by transient discharge followed by a glow discharge in positive polarity at lower conductivities propagating inside the bubbles. At high conductivities, the glow regime is particularly replaced by a more energetic sequence of transient discharges followed by a shorter glow mode operation. The transient regime probability and its intensity are higher in the negative discharge polarity. The transient discharge produces acoustic waves and shock waves, which are observed at the moment of the bubble cavitation. The average gas temperature of 700-1500 K was calculated from the lowest OH (A-X) 0-0 band transitions. The average electron concentrations of 10(20)-10(23) m(-3) were calculated from H alpha and H beta line profiles. Finally, the production of a chemically active species is determined by hydrogen peroxide energy yields related to the energy consumption of the whole interelectrode system. All these quantities are dependent on the solution conductivity, the discharge polarity, and the applied power

discharge in water solutions; fast camera visualization; discharge operation; discharge diagnostics; electron concentration; hydrogen peroxide

discharge in water solutions; fast camera visualization; discharge operation; discharge diagnostics; electron concentration; hydrogen peroxide

KRČMA, F.; KOZÁKOVÁ, Z.; MAZÁNKOVÁ, V.; HORÁK, J.; DOSTÁL, L.;OBRADOVIC, B; NIKIFOROV, A; BELMONTE, T

2019

04.06.2018

0963-0252

PLASMA SOURCES SCIENCE & TECHNOLOGY

27

6

United Kingdom of Great Britain and Northern Ireland

065001-1

065001-15

15

https://iopscience.iop.org/article/10.1088/1361-6595/aac521

psst_27_6_065001