Influence of nitrogen impurities on the characteristics of a patterned helium dielectric barrier discharge at atmospheric pressure

Abstract

In this paper, a two-dimensional axisymmetric fluid model was established to investigate the influence of nitrogen impurity content on the discharge pattern and the relevant discharge characteristics in an atmosphere pressure helium dielectric barrier discharge (DBD). The results indicated that when the nitrogen content was increased from 1 to 100 ppm, the discharge pattern evolved from a concentric-ring pattern into a uniform pattern, and then returned to the concentricring pattern. In this process, the discharge mode at the current peak moment transformed from glow mode into Townsend mode, and then returned to glow mode. Further analyses revealed that with the increase of impurity level, the rate of Penning ionization at the pre-ionization stage increased at first and decreased afterwards, resulting in a similar evolution pattern of seed electron level. This evolution trend was believed to be resulted from the competition between the N 2 partial pressure and the consumption rate of metastable species. Moreover, the discharge uniformity was found positively correlated with the spatial uniformity of seed electron density as well as the seed electron level. The reason for this correlation was explained by the reduction of radial electric field strength and the promotion of seed electron uniformity as pre-ionization level increases. The results obtained in this work may help better understand the pattern formation mechanism of atmospheric helium DBD under the variation of N 2 impurity level, thereby providing a possible means of regulating the discharge performance in practical application scenarios.

Influence of Oxygen on the Multiple-Current-Pulse Behavior in an Atmospheric Homogeneous Helium Dielectric Barrier Discharge With Air Impurities

“…In the previous studies on He and He/N 2 [4], [16], [23], [37], [38], the influence of n e0 on the evolution of MCP discharges was obvious and thus discussed thoroughly. In this study, however, it is found that n e0 remains basically unchanged when the air content is increased above 500 ppm (namely, in stage II).…”

“…Thus the attachment reaction is one of the important differences between the chemical reactions regarding O 2 and N 2 . In our previous studies about MCP discharges [16], [23], [38], we have neglected the effect of the O 2 impurity, thus certainly without considering the O 2 attachment reaction. As stated earlier in Section III.A, the O 2 attachment reaction will become stronger as the proportion of air content increases.…”

Partial Discharge Simulation of Air Gap Defects in Oil-Paper Insulation Paperboard of Converter Transformer under Different Ratios of AC–DC Combined Voltage

“…Based on the work of previous researchers, the simulation model in this paper considers the main particles and chemical reactions in the air [28]. The main particles considered are: electrons, N [28,30]. Additionally, the chemical scheme is shown in the Appendix A (Tables A1 and A2).…”

“…The previous research of our research group shows that in the partial discharge with a similar geometric size, the photoionization reaction will not affect the discharge morphology of partial discharge. Therefore, photoionization is not considered in this paper [27,28].…”

How does the moderate wavy surface affect the discharge behavior in an atmospheric helium dielectric barrier discharge model?

“…As regards the chemical scheme, we reuse the one that has been previously validated in our 1D and 2D DBD simulations . More specifically, the gas gap is filled with helium and small amounts of nitrogen impurities (100 ppm).…”