Numerical simulation of dielectric barrier discharge in Ar/He and Ar/O2 mixtures at atmospheric pressure

This study presents a numerical investigation of dielectrique barrier discharge (DBD) at atmospheric pressure, focusing on two gas mixture: Ar/He and Ar/O2. The objective is to analyse the impact of dielectric permittivity on the plasma behavior in the Ar/He mixture, and the influence of the gas temperature in the Ar/O2 mixture. For the Ar/He case, the relative permittivity of the dielectric is varied from 2 to 12, considering 7 species and 10 chemical reactions. In the Ar/O₂ case, the gas temperature is increased from 350 K to 600 K, with 9 species and 24 chemical reactions taken into account. Key plasma parameters such as species number densities (both neutral and charged), electron temperature, and electron density are evaluated for each scenario. Simulation results for the Ar/He mixture show that increasing dielectric permittivity does not affect the number densities of Ar, He, He⁺, or Hes, but leads to increased densities of electrons, Ars, Ar⁺, and a rise in electron temperature. For the Ar/O₂ mixture, increasing gas temperature causes a reduction in all species densities, while simultaniously increasing the electron temperature.