Hydrodynamic loading of ceramic components due to electrical discharge in water

For one kind of high-current electron accelerators based on water pulse forming line (PFL) and ceramic sealed vacuum diode, the mechanical stability of the water-vacuum interface should be taken into account during operation. One threat derives from the shockwaves initiated by water breakdown in the PFL. In this paper, the water shock due to electrical discharge was numerically and experimentally investigated. By combining empirical formulae for plasma driven water shock theory with a underwater explosive approach, finite element models were set up to simulate the shockwave pervasion sequence. The pressure-time history and mechanical response to pressure waves were also obtained. In order to get the pressure profile, the arc pressure test including “point-plane” electrode system was carried out based on a 10-stage Marx generator. Peak pressure of water shock was measured by the sensor and related results have a close approximation to the predictions. The relationship between shockwaves and discharge energy was also obtained in the experiments.