ULTRASOUND INDUCED CAVITATION AND SONOCHEMICAL YIELDS

The introduction of a strong acoustic field to an aqueous solution res ults in the generation of cavitation microbubbles. The growth and coll apse of these microbubbles focuses and transfers energy from the macro scale (acoustic wave) to the microscale (vapor inside the bubbles) pro ducing extremely high localized pressures and temperatures. This uniqu e energy focusing process generates highly reactive free radicals that have been observed to significantly enhance chemical processing. This paper presents a model that combines the dynamics of bubble collapse with the chemical kinetics of a single cavitation event. The effects o n sonochemical yields and bubble dynamics of gas composition and heat transfer are assessed and compared with previous theoretical and exper imental studies. Results from this model are used to explain unusual e xperimentally observed sonochemical phenomena. (C) 1998 Acoustical Soc iety of America. [S0001-4966(98)06611-9].