Optical and electric diagnostics of DBD plasma jet in atmospheric pressure Argon

Two cold Argon atmospheric pressure plasma jets were generated based on the form of DBD configuration device. One device equipped with one powered ring electrodes as well as a grounded ring electrode, and the other´s grounded electrode was a metal plate. The characteristics of two different plasma jets with mid-frequency sinusoidal power were measured in this paper. The waveforms of the applied voltage and discharge current, Lissajous figures, images and optical spectrum of DBD were acquired, when Ar was inlet. The transported charges, discharge power and electron excitation temperature were investigated through Lissajous figures. Moreover, the optical emission spectroscopy is used to measure the plasma parameters, of which the electronic excitation temperature is determined by the Boltzmann´s plot method using seven characteristic lines of Ar. The experimental results indicate that, discharge power and electronic excitation temperature of two plasma jets increase with the applied voltage. Through investigating the two plasma jets´ electricity and optical characteristics, it was found that, compared to one plasma jet generated by the device with a grounded ring electrode, the other plasma jet generated by the device with a grounded metal-plate electrode had smaller discharge power but higher electron excitation temperature when under the same applied voltage and Ar flow rate.