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

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.

Automated summary

The study investigates the spatiotemporal dynamics of positive and negative streamers in a pin-to-plate volume dielectric barrier discharge, revealing different discharge characteristics for each. Positive streamers rely on electron avalanches caused by photoelectrons for spatial propagation, while negative streamers do not. Additionally, the study uncovers floating positive surface discharges when positive streamers reach dielectric walls, and explores the interactions between positive streamers and dielectric pores.