Particle-in-cell Simulation Of Dielectic Barrier Discharge

Dielectric Barrier Discharge (DBD), with unique characteristics: high energy,generated under high pressure, has been widely applied in environmental engineering,ozone generation, material surface modification, medical sterilization, and otherfields.The plasma discharge process is very complex. The conventional plasmaexperimental diagnosis can only obtain many parameters of discharge process, but itis difficult to understand the interaction process and mechanism of DBD. In order tofurther understand the discharge characteristics and its mechanism, two kinds ofdielectric barrier discharge process is simulated by two-dimensional PIC-MCCmodel.(1) Microdischarge process in Plasma Discharge PanelBased on numerical simulation of dielectric barrier microdischarge near theatmospheric pressure，the distribution of charged particles number density, electricpotential and electric field distribution could be obtained. And the distribution ofincident angle and the incident energy of incident ions near the electrode, and thestriation phenomenon were also discussed. Simulation results show that, with theaccumulation of electron near the surface of electrode, the built-in electric fieldcaused by charged particles gradually began to play a major role within the process ofdischarge. At the same time, the electric field inside the discharge space became moreand more small, and tended to be stable. Striation phenomenon appeared in theprocess of micro discharge, is strongly related to the particle density distribution inthe process of discharge, the electric potential distribution and the surface chargedistribution near the surface of dielectric. The dielectric layer near the electrodeplayed an important role in the process of discharge, and ion incident angledistribution and incident energy distribution near the dielectric layer of the electrodes were extremely important to the lifetime of the electrode.(2)Radio-frequency dielectric barrier discharge process under atmosphericpressureBased on numerical simulation of radio-frequency dielectric barrier dischargeprocess under atmospheric pressure, the spatiotemporal distribution of chargedparticles density, the electric potential distribution and the electric field distributionwere obtained. And the filamentous discharge was also discussed. Simulation resultsshow that the existence of the dielectric layer made the electron accumulatecontinually on the dielectric surface, and formed a built-in electric field, whichprevent the filamentous discharge to form the arc discharge and made the dischargebecome more uniform.