Numerical study on heat transfer effects of cavitating and flashing flows based on homogeneous mixture model

摘要

A numerical study on heat transfer effects of cavitating and flashing flows was conducted by employing a compressible homogeneous mixture approach. A dual-time preconditioned method was applied to enhance the efficiency and accuracy of the computations under various flow conditions. A sensitivity analysis of the empirical coefficients used to access the predictive capability of the existing mass transfer models was assessed for cavitating flows in a converging-diverging nozzle. To confirm the use of the calibrated empirical coefficients, computations of the water flows over a cylindrical head form and a Clark-Y hydrofoil were then carried out. The results obtained indicate an overall good agreement with the experimental data. Finally, the thermal effects on the phase change process were confirmed through an examination of a flashing flow along with thermo-fluid flows. The predicted results also show a good agreement with the experimental data. In conclusion, the existing system was shown to be effective in quantitatively predicting the thermal effects of the phase change processes, and can be used to examine the hydro- and thermodynamics of multiphase flows.