Comparative study of dielectric barrier discharge characteristics of methane-air mixed He/Ar

To examine the influence of various kinds and doping ratios of inert gases on the discharge properties of methane-air mixtures in coaxial dielectric barrier discharges, a numerical simulation of the discharge process was performed utilizing a plasma model to examine the variations in electron density and the number densities of CH3 and OH inside the discharge region. The study's findings indicate that the working gas used in the CH4-Air combination caused the electron density of the discharge to rise sharply to its highest point in the early stages before gradually declining over the discharge time. The number of active particles CH3 and OH has always been in the state's growth, and the electron temperature in a discharge cycle presents two extreme value points. When the gas mixture is doped with the noble gas Ar, the electron density gradually decreases as the proportion of Ar in the gas mixture increases; the number densities of CH3 and OH increase when the gas volume ratio is VAr:VCH4:VAir = 1:30:300, but drop when the amount of doped inert gas rises to VAr:VCH4:VAir=1:10:100; following the switch from Ar to He as the dopant gas in the CH4-Air mixture, the electron density marginally rises but the number densities of the active particles CH3 and OH sharply decline with the number density of CH3 decreasing by up to around 6%.