Numerical simulation of air DBD under standard atmospheric pressure

Abstract

In order to study the mechanism of dielectric barrier discharge (DBD) producing non-equilibrium plasma, the DBD equipment was simplified into a one-dimensional model. The AC power supply voltage was set as 18 kV, the frequency was set as 10 kHz, and the discharge medium was N2 and O2 with a mass fraction of 4:1 to simulate the air. The impact cross-section, electron mobility and initial electron temperature of the discharge reaction were determined by BOLSIG+. The electric potential field diagram, voltage current relation diagram, electron density diagram, temperature distribution diagram and electron energy distribution function EEDF diagram are obtained. The results show that the electric field reaches the maximum near the gap sheath. Due to the generation of an additional electric field, the current density reaches the maximum at the rising edge of the air gap voltage. The continuous ionization of air particles in the discharge process leads to the accumulation of electrons and the formation of electron collapse, which leads to the increase in electron density and the decrease in electron temperature. As the reduced electric field E/N increases, the proportion of high-energy electrons in the total electron number increases. At this time, the reaction of non-equilibrium plasma intensifies, and more active substances can be produced.