Research On DBD-Based The Space Periodic Boundary

The non-thermal equilibrium plasma produced in Dielectric Barrier Discharge (DBD) can be applied to the field of material handling, pollution control, biological sterilization. Because of the good prospect, it has become a hot research topic to domestic and foreign scholars in recent years. In this experiment, the space periodic boundary is changed by using different stainless steel net and different layout. Then the effect of discharge has been researched by changing the mesh size, voltage, frequency, pressure. And the Indigo wastewater treatment has been studied by DBD assisted by wire mesh in a gas-liquid two-phase mixture.In the experiment, It was found that when the mesh size larger than 250μm, the micro-discharge along the wire. When the mesh size smaller than 200μm, the discharge distributed at random. The discharge became strong, as the voltage and frequency increasing. The Initial discharge voltage reduced, and the discharge became diffusion, as the pressure decreasing. The major peak phenomenon has been observed in argon gas at 0.25Mpa. According to the analysis of the discharge photos and the current waveform, we think that the electric field is more uniform, the discharge is glow discharge, which caused the major peak of current waveform. But the electric field around the electrode occur distortion, the discharge is filamentary discharge, which caused the pulses of current waveform.The current waveforms obviously exist the polarity effect, with mesh electrode structure. The current waveform is different in the positive and negative half-cycle voltage, caused by the asymmetric electrode structure. In this paper, We found the polarity effect reduced, as the he voltage and frequency increasing. And we analyzed the effect to polarity effect from accumulated charges,space charges and corona.We proposed a simulation model of DBD, which is suitable for this experimental setup. According to the simulation, we considered that the conductivity of gas is different in the positive and negative half-cycle voltage, caused by accumulated charges,space charges and corona. The resistance equivalents to the change of conductivity. And the results of simulation consistent with the measured results.We found the mesh could make the discharge rule distribution, in the gas-water two-phase mixture DBD assisted by wire mesh. But the discharge became random, when the mesh size smaller than 5mm. Through the Indigo wastewater treatment, we found that the most obvious treatment effect came about two minutes after the start of discharge. This is a new way for industrial water treatment, use of dielectric barrier discharge. This unique two-phase structure can also be used for gas treatment.