DEVELOPMENT OF HIGH SPEED PHOTOGRAPHY TECHNIQUE FOR UNDEX APPLICATIONS

This paper describes recent experimental development of high speed photography (HSP) applied to UNDer water Explosive (UNDEX) trials. The imaging technique adopted used overhead mirrors and a Perspex® plate on the surface of the water in a tank holding 11,000 litres of water. The HSP has identified the shock wave velocity, shape and timescales and the bubble dynamics as well as the interaction with the target (i.e. Glass reinforced panel (GFRP) composite panel). Charge sizes ranged from 40-140g of PE4 explosive and good images were obtained of the target response. Improvements to the technique will be higher fidelity to enable Digital Image Correlation (DIC) measurements for the panel as well as improved target fixings to prevent lateral motion so that damage could be induced in the panel. The technique can also be used on bigger scale UNDEX trials.