空化发生时,热力学效应使得流场内温度发生变化,从而通过气泡界面与液体的传热控制气泡的生长。本文考虑了这一空化热力学的影响,对已有的热力学空化模型进行了改进;采用改进的空化模型对NACA0015翼型及一种超小型泵在25℃和100℃下的空化流场进行了模拟。通过与实验值对比,验证了模型的有效性。研究表明在高温环境下空化的热力学效应显著,其影响不可忽略;在高温时空化的热力学效应抑制了超小型泵空化,从而改善了泵的空化性能。
When cavitation occurs, the temperature in the flow would change due to the thermody- namic effects. Thus, the bubble growth can also controlled by the heat transfer between liquid and vapor-liquid interface. In the paper, by considering the heat transfer, an improved thermodynamic cavitation model has been developed. Further, the cavitating flows for a NACA 0015 hydrofoil and a mini pump are simulated with the improved model. Through the comparison with experimental data, the cavitation model has been validated. The results indicate that the cavitation thermodynamic effect can not be neglected at high temperature water in those cases. Besides, the cavitation in a mini pump at high temperature water is obviously suppressed and the cavitation performance is improved.