混流式水轮机转轮双向流固耦合力学特性研究

为了解运行过程中的水轮机叶片应力、应变和流场的分布状况及规律,以某高比转速混流式水轮机为例,采用双向流固耦合算法,对其转轮叶片的应力应变情况和内部流动特性进行了研究和计算分析。研究结果表明,在高转速小流量的工况下,叶片的最大变形出现在出水边的下部,出水边中部也出现了比较大的变形,叶片的进水边、出水边与上冠及出水边与下环的相连接处出现了集中应力;在其他工况下,叶片的最大变形出现在出水边的中部,集中应力出现在叶片出水边与上冠的相连接处。该水轮机在正常运行的情况下,转轮叶片的变形很小,对内部流场的影响不大。因此,如果只是对水轮机进行水力性能方面的分析,则没有必要进行双向流固耦合计算。

Study on mechanical properties of two-way fluid-structure interaction of Francis turbine runner

For a high specific speed Francis turbine , the stress and strain condition of runner blade and the internal flow char-acteristics were calculated and analyzed by using the method of two -way fluid solid coupling algorithm .The results show that un-der high rotating speed and small flow , the maximum deformation occurs at the lower position of blade tail edge and with relative large deformation at the blade tail edge centre , the stress concentrates at the blade head edge , tail edge, hub, joint position of tail edge and shroud;for other conditions , the maximum deformation of blade is at blade tail edge centre and the stress concen -trates at the joint position of tail edge and hub .The blade deformation is small when the turbine runner operates normally and has little impact on the turbine internal flow field .The two-way fluid solid coupling calculation is unnecessary if only the hydraulic performance of turbine is needed to be analyzed .