Simulation On Resistance And Dielectric Barrier Glow Discharge At Atmospheric Pressure

For the non-equilibrium plasma produced at atmospheric pressure, its electrons are of higherenergy and its ion energies are lower. Especially, it contains a lot of active particles. Theseparticles can reduce the threshold of chemical reactions with other corresponding matters.Therefore, many chemical reactions can occur in low temperature as well as in room temperaturein the non-equilibrium plasma. Due to the above, the non-equilibrium plasma is widely used inindustrial applications and the plasma physics scientific community has paid much attention to thedevelopment of atmospheric pressure non-equilibrium plasma. With the wide application of thenon-thermal plasmas in various field,the generation of homogeneous non-thermal plasmasthrough gas discharge at atmospheric-pressure has become one of the most attractive researches inthe field of gas discharge and non-thermal plasmas. Dielectric barrier discharge (DBD) is a kind ofpulsed discharge with at least one dielectric layer inserted in discharge path. Through the study ofthe atmospheric pressure dielectric barrier discharge, we obtain the best conditions of stabledischarge by changing external discharge conditions of simulation data. Then this will reduceunnecessary waste of the experimental resource in the application. This paper will use thesinusoidal voltage source excitation and join the resistance which reflect the unique superiority ofit. To this end, in this thesis the atmospheric-pressure pulsed DBD has been systematicallyinvestigated by means of numerical simulation with the use of a one-dimensional fluid model, andthe main contents and results are summarized as follows:The research content is divided into two parts: the first part is the effects of amplitude increaseof applied sinusoidal voltage, sinusoidal voltage frequency and the relative permittivity.Currentdensity,particle density is the main research. Through the analysis of the data, a lot of numberof current density and current peaks by the applied voltage.And the relative permittivity also willaffect the number of current peak. The second parts is developed for resistance dielectric barrierdischarge in atmospheric helium, which was employed for investigating the multi-peak behaviorof discharge current density excited by sinusoidal voltage at repetitive frequency of5kHz. Itsuggests that with introducing the resistors (100～500k), the number of discharge currentdensity peak is reduced, and the amplitude of discharge current density goes down, which can beexplained by the waveforms of gas voltage and resistor voltage, corresponding to that of thedischarge current density. The discharge dynamics is illustrated by the spatio-temporal evolutionof electron density, electric field and first Townsend coefficient in discharge gap. This numericalstudy proposes a way to improve the discharge stability of atmospheric dielectric barrier dischargeby introducing resistance.The result is with the amplitude of voltage and the frequency of voltage increase, thedischarge of current density is increase. With the relative permittivity decrease, the discharge ofcurrent is decrease. It is easy to form filaments discharge mode,so the external resistance willlimit the growth of current and prevent the formation of filamentary discharge. At last, theformation of stable discharge current contributes to the further experiment.