Numerical simulation of discharge mode conversion with multiple current pulse (MCP) in atmospheric pressure He/N2 dielectric barrier discharge

Abstract

A one-dimensional fluid simulation model of He/N2 dielectric barrier discharge with parallel plate electrodes was established to study the effects of different parameters (such as gap width, secondary electron emission coefficient γ, and driven frequency) on the characteristics of multiple current pulse (MCP) discharge and the discharge mode conversion. The discharge can be divided into Townsend discharge, transition state, and glow discharge. The results show that with the increase in γ, the number of discharge current pulses increases, making it more difficult to form a glow discharge. When γ is larger, the first discharge approaches the glow discharge mode, but the positive column region is not completely formed, and the subsequent discharge sequence undergoes a transition state to Townsend discharge gradually. Under the condition of larger γ, MCP discharge with a short gap is Townsend discharge. With the increase in the gap width, the transition state will appear in the first discharge, and the subsequent discharge sequence may be converted into Townsend discharge. When the gap width increases further, the discharge can be completely transformed into glow discharge. The pulse number of discharge current decreases with the increase in frequency, and the higher frequency is conducive to the formation of glow discharge.

Multiple current peaks and spatial characteristics of atmospheric helium dielectric barrier discharges with repetitive unipolar narrow pulse excitation

“…It should be noted that this phenomenon of multiple electron density peaks caused by multiple current peaks has also been reported in experimental and numerical studies [58,70]. However, in AC DBDs, the appearance of multiple current peaks is hard to be accompanied by multiple electron density peaks [13,71]. Compared with AC DBDs, the time interval between two adjacent current pulses in DBDs driven by narrow pulse excitation is short.…”

Review of numerical simulation of atmospheric-pressure non-equilibrium plasmas: streamer discharges and glow discharges

“…The details of DBD in helium have been elucidated in recent years, such as the influence of oxygen content on the efficiency of reactive oxygen species (ROS) production, 191) the influence of the voltage waveform, 192) the effects of different parameters (e.g. gap width, secondary electron emission coefficient, drive frequency) on the discharge mode conversion, 193) and DBD with a ring electrode configuration. 194) The use of nitrogen for an atmospheric-pressure homogeneous plasma is preferable to noble gases, such as helium, from the viewpoint of industrial use.…”

Numerical simulation study of ionization characteristics of argon dielectric barrier discharge

“…However, they did not take into account how the structural parameters of the physical model would affect the characteristics of ionization. [16] Wang et al [17] used a one-dimensional fluid simulation model of a He/N 2 dielectric blocking discharge with parallel plate electrodes to investigate the law of the effect of different gap widths, secondary electron emission coefficients and driving frequencies on the characteristics of the multi-current pulse discharge and transition of the discharge mode. The process of discharge mode transition was further explored when the parameters changed, but the effect on the particle discharge characteristics was ignored.…”

“…The process of discharge mode transition was further explored when the parameters changed, but the effect on the particle discharge characteristics was ignored. [17] Apart from assisting the effort to establish the correlation between the structural parameters, working parameters and performance indices of the discharge exciter, the results of qualitative and quantitative analyses of the internal working process and its influencing factors also provide a crucial reference for the design and development of the discharge exciter and accelerate the development cycle. It is thus necessary to reveal the rationale of the DBD exciter and identify its influencing factors.…”