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Downloaded Fshift the cavitation regions. The objective of the present study is to develop a practical cavitation model capable of predicting major performance parameters. Its extensions to prediction of cavitation related surface damage, which affects the life of the equipment, may be considered in future. Numerical simulation of cavitating flows poses unique chal-lenges, both in modeling of the physics and in developing robust numerical methodology. The major difficulty arises due to the large density changes associated with phase change. For example, the ratio of liquid to vapor density for water at room temperature is over 40,000. Furthermore, the location, extent and type of cavi-tation are strongly dependent on the pressure field, which in turn is influenced by the flow geometry and conditions. Therefore, in a practical modeling approach, a priori prescription ~or assumption! of the location and/or size of cavitation region should not be re-quired. Likewise, the phase change correlations should have mini-mum essential empiricism so that diverse applications can be simulated without adjusting any constants or functions. Over the last several decades, considerable effort from both experimental and analytical fronts has been devoted to under-standing cavitation. For example, References @1–12 # include some recent reviews as well as attempts on modeling and application of cavitation. Unfortunately, all past models, including the two de-Description of the Full Cavitation Model The basic approach consists of using the standard viscous flow ~Navier-Stokes! equations for variable fluid density and a conven-tional turbulence model ~e.g., k- « model!. The fluid density is a function of vapor mass fraction f, which is computed by solving a transport equation coupled with the mass and momentum conser-vation equations. The r-f relationship is