This paper reports on the application of hydrodynamic cavitation by the use of submerged cavitating liquid jets to trigger widespread cavitation and induce oxidation of organic compounds in the bulk liquid solution with a two order of magnitude increase in energy e¢ciency compared to the ultrasonic means.The results are compared to a bubble dynamics model that includes heat and mass transport, collective bubble e¤ects, and a …rst order Arrhenius reaction rate model. Comparison of model results with experiment indicated the reactions were limited by contaminant transport to the bubble surface rather than by radical generation or the intensity of bubble collapse. Other …ndings are the desirability of operating at atmospheric ambient pressure and low driving pressures and of maximizing cavity surface area. These results suggest a great potential for the use of jet cavitation in practical scale waste treatment and remediation systems.

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We have developed a three-dimensional BEM based code (3DYNA YNAFS Ó ) to study nonlinear free surface flows. The code is being used here to study bubble dynamics, such as that due to an underwater explosion, beneath surface piercing bodies. Six degree-of-freedom rigid body motion of the surface piercing bodies are modeled producing a fully coupled fluid-structure interaction effect simulation. Validation of the code is presented by comparison of simulations with laboratory experimental data obtained from high speed video recordings of surface piercing bodies interacting with bubbles generated by electric spark discharge. Two cylindrical body configurations are considered under both free floating and rigidly constrained conditions. The results of the numerical simulation show very good comparison to the experimental data in terms of bubble shapes and periods, the time evolution of the bubble and the induced motion of the bodies.

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