轴流式水轮机全流道内非定常空化湍流的数值模拟

为了研究轴流式水轮机内部的空化流动,将Fluent 6．1商用软件中的一种完整空化模型和一种混合流体两相流模型相结合,对某水电站原型轴流式水轮机全流道内的非定常空化湍流进行了数值模拟。根据模拟结果,预测了水轮机在特定工况下运行时流道内空化发生的部位和程度,并对水轮机的能量性能进行了预估。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轴流式水轮机的运行性能预测提供参考。

NUMERICAL SIMULATION OF UNSTEADY CAVITATING TURBULENT FLOW IN THE WHOLE FLOW PASSAGE OF A KAPLAN TURBINE

In order to study the cavitating flow in a Kaplan turbine, the numerical simulation with a full cavitation model and a mixture two-phase flow model, which are in commercial code Fluent 6.1, has been performed to the unsteady cavitating turbulent flow within the whole flow passage of a Kaplan turbine in a hydraulic power plant. Based on the simulating results, the region and the degree of cavitation occurred in the flow passage of the turbine running in a given working condition are predicted, the energy performance of the turbine is also evaluated. The predicted cavitation phenomena coincide with those observed in the cavitation experiment to a corresponding model turbine. It shows that the numerical simulation results can provide references for the running performance prediction of a Kaplan turbine.