A 1-D fluid model coupled with an external circuit is proposed to study the Xe dielectric barrier discharge (DBD) under a 50-kHz ac sinusoidal voltage. The impact of ions and photons on barrier surfaces and the thermal motion of charged particles in the sheath are taken into account in this model. The spatial and temporal distributions of electrons, ions, and excited, resonance, and metastable particles are investigated. The experimental investigations on discharge current densities under different voltage source amplitudes are analyzed and compared with simulation results. The results reveal that, with the increment of voltage source amplitudes, the waveforms of gas gap voltage and discharge current all move forward the applied voltage, showing a gradually decreased phase shift, which is in good agreement with the experimental observations. The evolution of surface charges accumulated on dielectric barriers can be divided into six stages during an ac cycle, and they play a key role in the ignition and extinction of the discharge. It is concluded that, while the charge difference between the surfaces of a two-side dielectric is up to a certain value and the applied voltage is low enough, the gas breakdown will occur. The spatiotemporal variations of particle densities and electric field indicate that the Xe DBD under the conditions considered in this paper is a typical glow discharge. Furthermore, the electron emission brought by impact of photons on dielectric surfaces can accelerate gap breakdown and strengthen the intensity of the discharge, and the sheath phenomenon is more obvious under the consideration of thermal motion of charged particles in boundary conditions.
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