Observation of virtual capacitance between barrier discharge plasma and dielectric electrode

Abstract

Summary form only given. The virtual boundary layer between the atmospheric discharge plasma and the dielectric barrier electrode was observed in atmospheric dielectric barrier discharge plasma. With considering the capacitance formed in the boundary layer, the accuracy of analyzing the dissipated power from the charge-voltage Lissajous diagram can be improved. Observations show that the boundary layer has the similar property of the sheath. The thickness of the boundary layer on the electrodes is proportional to the discharge density in the Townsend-mode discharge and to the applied voltage in the diffusive streamer-mode discharge, respectively. In the glow like discharge using the helium plasma, the thickness is proportional to the 2/3 power of applied voltage over the square root of the discharge density, which is very close to the collisional sheath property. The alpha-gamma transition effect on the boundary layer formed at the conducting electrodes is also investigated. Experiments were carried out with the parallel cell reactor having at least one of dielectric electrodes. The reactor capacitance was varied with changing the gap distance. The system is closed so that the gas was fed between the electrodes and exhausted the other side. The gas flow was controlled to minimize the perturbation of the discharge. Operating frequency is lower than a few hundred kilohertz. The property of the boundary plasma on the electrodes will be discussed