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

Abstract

The streamer dynamic evolution and discharge mode transition of three-electrode surface dielectric barrier discharge (SDBD) driven by repetitive pulses are studied experimentally and numerically for better plasma-mode controlling and optimized application. Spatial-temporal plasma morphologic features together with electro-optical behaviors are utilized to analyze the streamer dynamic evolution and streamer-to-spark transition. To have a deep insight into the physical mechanism of the discharge mode transition in repetitive pulses, a 2D fluid model combined with 0D kinetic model is built and studied. A good agreement between experimental measurements and numerical simulation in the propagation dynamics and voltage-current characteristics is achieved. Results show that the surface-streamer discharge in the form of primary and transitional streamers can transform into a surface-spark discharge characterized with 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. The most electrons can be released from the negative charges by oxygen atoms during the inter-pulse period, which is favor to the re-ignition and ionization process of the subsequent pulse discharge.