采用一种完整空化模型和一种混合流体两相流模型,对轴流式水轮机全流道内的定常空化湍流流动进行了数值模拟。根据模拟结果,考察了水轮机在低尾水位下运行时流道内空化发生的部位和程度,并对水轮机的空化性能进行了预估。数值预测的空化流动现象与模型水轮机空化试验中所观察到的现象基本一致,说明数值模拟结果可为水轮机的空化性能预测提供参考。
Numerical simulation of the steady cavitating turbulent flow in the whole flow passage of a Kaplan turbine has been carded out by using a full cavitation model and a mixture two-phase flow model. Based on the simulatiori results, the region and the degree of cavitation occurred in the flow passage of the turbine with a low water level at the outlet of the draft tube are examined, the cavitation performance of the turbine is also evaluated. Basically, the predicted cavitation phenomena coincides with those observed in the experiment for a corresponding model turbine, it indicates that the simulation can provide reference for the cavitation performance prediction of other turbines.