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DOE OSTI · 2562920

Plasma-Bubble Imaging and Spectroscopy (Final Report)

Stapelmann, Katharina [North Carolina State University, Raleigh, NC (United States)] (ORCID:0000000221162661)
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Abstract

The aim of this research was to capture time- and space-resolved behavior of breakdown initiation and development in water with gas bubbles injected between the electrodes when excited with microsecond voltage pulses. The results were directly compared to our previous results from a PCRF collaboration on the development of an electrical discharge in a gas bubble immersed in liquids with different conductivities when excited by nanosecond voltage pulses. For nanosecond regimes, cavitation seems to play a major role in plasma breakdown for low conductivities and discharge initiates at an electrode. On microsecond timescales, where cavitation does not play a role, it has been hypothesized that breakdown in water occurs first in bubbles on or near the electrodes, pre-existing or formed thermally.

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Stapelmann, Katharina [North Carolina State University, Raleigh, NC (United States)] (ORCID:0000000221162661). 2025-04-28. Plasma-Bubble Imaging and Spectroscopy (Final Report). https://doi.org/10.2172/2562920

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