Influence of gas pressure on plasma parameters in a dielectric barrier discharge plasma actuator

A uniform discharge seen with naked eyes is observed with an asymmetrical dielectric barrier discharge (DBD) plasma actuator. By using the optical emission spectrum method, the plasma parameters at different gas pressures are investigated. The molecular vibration temperatures are calculated by the spectra lines of N2 second positive band system (C3Πu → B3Πg), the electron excitation temperatures are calculated by the relative intensity ration of spectral lines of Ar I 763.51 nm (2P6 → 1S5) and Ar I 772.42 nm (2P2 → 1S3), and the electron densities are compared by comparing the broadenings of Ar I (2P2 → 1S5) spectra lines, respectively. It is found that the molecular vibration temperature and the electron excitation temperature decrease when the gas pressure is increased, while the electron density increases.