本文充分考虑不可凝结气体、表面张力、压力脉动和湍动能的影响,对空化模型进行了修正。利用修正了的空泡质量传输方程,对某电站水轮机模型机的空化现象进行了数值模拟,并与实验结果进行了对比。从空泡体积分布、效率与空泡数的关系验证了空化模型的合理性。转轮叶片表面上的压力分布在非空化和空化两种工况下进行了对比分析。小流量工况下转轮叶片进口边的流动分离导致了转轮叶片头部的压力分布曲线的扭曲,并与转轮叶片上空化的发生存在一定联系。
In this paper, a modified cavitation mass transfer equation considering the non-condensable gas, surface tension, pressure variation and turbulence energy is proposed based on evaporation and condensation mechanics. The modified cavitation model is used to simulate the flow in a model Francis turbine on different Thoma number The predicted efficiency and cavitation bubble The pressure distribution is compared between The flow separation on the leading edge of the separation has some relation with cavitation. The results are compared with experimental data. volume distribution agree well with the experiment. the cavitation and no-cavitation working condition. blade leads the pressure curve distortion. The flow