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arXiv · 2209.14763

Evolution of positive streamers in air over non-planar dielectrics: Experiments and simulations

Hans Kristian Meyer·Robert Marskar·Frank Mauseth
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Abstract

We study positive streamers in air propagating along polycarbonate dielectric plates with and without small-scale surface profiles. The streamer development was documented using light-sensitive high-speed cameras and a photo-multiplier tube, and the experimental results were compared with 2D fluid streamer simulations. Two profiles were tested, one with 0.5 mm deep semi-circular corrugations and one with 0.5 mm deep rectangular corrugations. A non-profiled surface was used as a reference. Both experiments and simulations show that the surface profiles lead to significantly slower surface streamers, and also reduce their length. The rectangular-cut profile obstructs the surface streamer more than the semi-circular profile. We find quantitative agreement between simulations and experiments. For the surface with rectangular grooves, the simulations also reveal a complex propagation mechanism where new positive streamers re-ignite inside the surface profile corrugations. The results are of importance for technological applications involving streamers and solid dielectrics.

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Hans Kristian Meyer, Robert Marskar, Frank Mauseth. 2022-09-29. Evolution of positive streamers in air over non-planar dielectrics: Experiments and simulations. https://doi.org/10.1088/1361-6595/aca0be

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