Positive and negative streamer propagation in volume dielectric barrier discharges with planar and porous electrodes

Abstract

The spatiotemporal dynamics of volume and surface positive and negative streamers in a pin‐to‐plate volume dielectric barrier discharge is investigated in this study. The discharge characteristics are found to be completely different for positive and negative streamers. First, the spatial propagation of a positive streamer is found to rely on electron avalanches caused by photoelectrons in front of the streamer head, whereas this is not the case for negative streamers. Second, our simulations reveal an interesting phenomenon of floating positive surface discharges, which develop when a positive streamer reaches a dielectric wall and which explain the experimentally observed branching characteristics. Third, we report for the first time, the interactions between a positive streamer and dielectric pores, in which both the pore diameter and depth affect the evolution of a positive streamer.

DBD-like and electrolytic regimes in pulsed and AC driven discharges in contact with water

“…These structures occurring for the positive operation are similar to the well-known Lichtenberg figures occurring on dielectric surfaces after streamer impact [25,26]. It is often assumed that these pronounced and branched channels are a consequence of photoionization [25,27], which is more important for positive streamer propagation [28]. Moreover, these findings for the different morphologies of positive and negative discharges on dielectrics are in accordance with the literature, see e.g.…”

Fast breakdown process and characteristics diagnosis of nanosecond pin–pin discharge

“…After the initial breakdown stage, figure 6(b) shows that two filaments appear at the tips of the two needle electrodes, and the filament at the anode is weaker. The reason is that the acceleration of electrons toward the anode after the initial uniform discharge stage leads to the electron accumulation and a positive space charge region at the anode and cathode, respectively [28,29]. As a result, a weaker electric field at the anode and a stronger electric field at the cathode are formed under the influence of space charges [27], which leads to a stronger cathode filament and a weaker anode filament.…”

Propagation dynamics and interaction of multiple streamers at and above adjacent dielectric pellets in a packed bed plasma reactor

“…They also reported the role of these parameters on discharge dynamics. Zhang et al [18] computationally studied the interaction of streamers with pores inside dielectric boundary surfaces in DBDs and revealed the effects of pore diameter and depth on the propagation of streamers into such cavities. While streamer propagation through multiple dielectrics has been investigated, the interaction between adjacent streamers in a PBPR has not been considered to our knowledge.…”