NUMERICAL MODELING OF THE THERMODYNAMIC EFFECTS OF CAVITATION

A Navier-Stokes solver based on artificial compressibility and pseudo- time stepping, coupled with the energy equation, is used to model the thermodynamic effects of cavitation in cryogenic fluids. The analysis is restricted to partial sheet cavitation in two-dimensional cascades. Thermodynamic effects of cavitation assume significance in cryogenic fluids because these fluids are generally operated close to the critic al point and also because of the strong dependence of the vapor pressu re on the temperature. The numerical approach used is direct and fully nonlinear, that is, the cavity profile evolves as part of the solutio n for a specified cavitation pressure. This precludes the necessity of specifying specifying the cavity length or the location of the incept ion point. Numerical solutions are presented for two-dimensional flow problems and validated with experimental measurements. Predicted tempe rature depressions are also compared with measurements for liquid hydr ogen and nitrogen. The cavitation procedure presented is easy to imple ment in engineering codes to provide satisfactory predictions of cavit ation. The flexibility of the formulation also allows extension to mor e complex flows and/or geometries.