A reduced model of cavitation physics for use in sonochemistry

Abstract

Sonochemistry involves focusing acoustic energy through cavitation bubbles to increase chemical activity. The violent bubble collapses lead to temperatures of several thousand kelvin, which drive chemical reactions. In previous work, we gave a detailed computational model of a single bubble collapse, taking into account phase change, mass diffusion, heat diffusion and chemical reactions. All of these phenomena are important in determining the conditions at collapse. The present work involves development of a much simpler model that includes all the physics relevant to the determination of the reaction products. Comparisons with the more detailed computations are made; the reduced model is found to provide reasonable results. Furthermore, it is shown that many of the observed trends in sonochemistry are reflected in the trends observed in the behaviour of a single ‘representative' bubble.