Free-Lagrange Simulations of Shock/Bubble Interaction in Shock Wave Lithotripsy

Abstract

A Free-Lagrange CFD code is used to model the near-field interactions between a lithotripter shock wave and a single spherical air bubble in water in axisymmetric form. The shock wave interaction causes the bubble to collapse and undergo jetting which consequently generates a blast wave into the surrounding water due to a liquid-liquid impact. Following impact, the bubble attains a toroidal shape and undergoes subsequent expansion and collapse. A detailed description of the shock/bubble interaction event is given, which includes both primary and secondary collapse. Near-field pressure-time histories are presented.