Three-electrode surface dielectric barrier discharge driven by repetitive pulses: streamer dynamic evolution and discharge mode transition

The streamer dynamic evolution and discharge mode transition of a three-electrode surface dielectric barrier discharge (SDBD) driven by repetitive pulses are studied experimentally and numerically for better plasma-mode control and optimized application. Spatial-temporal plasma morphologic features together with electro-optical behavior are utilized to analyze the streamer dynamic evolution and streamer-to-spark transition. To gain a deep insight into the physical mechanism of the discharge mode transition in repetitive pulses, a 2D fluid model combined with a 0D kinetic model is built and studied. A good agreement between the experimental measurements and numerical simulation in the propagation dynamics and voltage-current characteristics is achieved. The results show that the surface-streamer discharge in the form of primary and transitional streamers can transform into a surface-spark discharge characterized by the primary streamer, transitional streamer and spark phase in repetitive pulses under the high applied electric field. A high gas temperature will result in a large reduced electric field after the transitional streamer, which exceeds the ionization threshold and thus promotes the discharge mode transition. A high number of electrons can be released from the negative charges by oxygen atoms during the inter-pulse period, which is favorable for the re-ignition and ionization process of the subsequent pulse discharge.