The physics of liquid impact, shock wave interactions with cavities, and the implications to shock wave lithotripsy.

This paper reviews research on the physics of liquid impact and the behaviour of cavities when a shock passes over them. It is shown that the problems are related since when a cavity collapses near a solid surface, or is collapsed by a shock wave, the collapse is asymmetric and a liquid jet is produced which can impact an adjacent solid. The implications of this research to shock wave lithotripsy are emphasized. Finally, the paper describes the development of a device, based on liquid jet impact, for fragmenting kidney stones.