Direct Measurement of the Shock Wave Pressure Produced by a Supersonic Discharge in Water Using a Het-V System

A pulsed power generator based underwater discharge system developed at Loughborough University is used to produce supersonic discharges that generate shock waves. The free surface dynamics of a 25 µm thick MICA sample mounted near the source is measured with a Het-V, aka Photon Doppler Velocimetry system developed at the Imperial College London. With the application of the Hugoniot data for water, the time profile of the shock wave pressure can be obtained. This direct measurement approach will allow the investigation of the attenuation region near the source where a shock wave becomes an acoustic pressure wave. The paper presents the very first data obtained during a preliminary experimental campaign. The way ahead includes tests in which an ultrahigh-speed camera will be used for schlieren imaging of the phenomena that will be collated with the shock wave pressure data.