Article

Investigation of the Atmospheric Helium Dielectric Barrier Discharge Driven by a Realistic Distorted-Sinusoidal Voltage Power Source

Plasma Chemistry and Plasma Processing (Impact Factor: 2.06). 02/2011; 31(1):1-21. DOI: 10.1007/s11090-010-9275-y

ABSTRACT

The non-equilibrium atmospheric-pressure parallel-plate helium dielectric barrier discharge (DBD) driven by a realistic 20kHz
distorted-sinusoidal voltage waveform has been investigated by means of simulations and experiments. A self-consistent one-dimensional
fluid modeling code considering the non-local electron energy balance was applied to simulate the helium DBD. The effect of
selecting plasma chemistry was investigated by comparing simulations with experiments. The results show that the simulations,
which include more excited helium, metastable helium and electron–ion-related reaction channels, can faithfully reproduce
the measured discharged temporal current quantitatively. Based on the simulated discharge properties, we have found that there
is complicated mode transition of discharges from the long Townsend-like to the “dark current”-like, then to the short primary
Townsend-like and the short secondary Townsend-like for the helium DBD that is driven by a realistic distorted-sinusoidal
voltage power source. Discharge properties in different periods of discharge are discussed in detail in the paper.

KeywordsTownsend-like discharge–Atmospheric pressure plasmas–Helium–Fluid modelling–Dielectric barrier discharge

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