1. College of Water Conservancy and Hydropower, Hohai University, Nanjing, Jiangsu 210098, China; 2. College of Energy and Electrical Engineering, Hohai University, Nanjing, Jiangsu 211100, China; 3. Institute of Innovation, Hohai University, Nanjing, Jiangsu 210098, China
Abstract：In order to investigate the thermodynamic effects on cloud cavitation dynamic characteristics, the accordance of numerical simulation with experiment was first validated, and then the thermodyna-mic effects on cavitation were investigated from aspects of temperature field, bubble radius and local cavitation number at different water temperatures. Based on the physical model of experiments, the simulation model was established, and the thermodynamic cavitation model and density corrected model(DCM)were applied to this cloud cavitation simulation around a hydrofoil with an angle attack of 8°. The results indicate that the calculated cavity structure coincides with the experimental results. Evaporation cooling leads to temperature drop inside the cavity, then saturation pressure decreases which suppresses the development of cavitation, and finally the attached cavity regions become smaller and thinner. Moreover, bubble radius decreases with the increase of free-stream temperature, which results in strong diffusion of bubbles and mistier cavity regions. Local cavitation number can directly reflect the effects of flow field temperature variation on the development stage of cavitation since the fluid physical properties change with temperatures.
