蒲石河电站水泵水轮机转轮S特性优化研究

Comparative Analysis of S-characteristics Before and After Impeller Optimization of the Pump Turbine in the Pushihe Pumped Storage Power Station

针对蒲石河抽水蓄能电站机组启动和甩负荷时水泵水轮机转轮S特性诱发的厂房振动问题,本文基于CFD数值仿真计算和模型试验对机组原9叶片转轮的S特性进行了分析研究,发现在S区工况运行时原转轮进口存在回流区,产成较大的水力损失,从而造成转轮的通流能力下降。基于此发现,本研究提出将9叶片转轮改为7叶片转轮的优化方案。通过对比CFD仿真结果及试验验证,新方案的转轮进口回流现象得到调整,从而有效改善了转轮“S”特性,解决了厂房振动的源头问题。实际工程的应用证明新方案起到了很好的效果,本方案思路可为同类型电站类似问题解决及老旧抽水蓄能电站改造提供参考借鉴。

To address the issue of plant vibrations induced by the S-characteristic of the pump-turbine runner during unit startup and load rejection at the Pushihe pumped storage power station,this study investigates the S-characteristic of the original 9-blade runner using CFD numerical simulations and model testing.It was found that during operation in the S-region,the original runner exhibits a recirculation zone at the inlet region of the runner,resulting in significant hydraulic losses and reduced flow capacity.Based on this finding,the study proposes an optimization solution of replacing the 9-blade runner with a 7-blade runner.Comparison of CFD simulation results and experimental validation indicates that the new solution effectively addresses the recirculation issue at the runner inlet,thereby significantly improving the S-characteristic and resolving the source of plant vibrations.Practical implementation confirms the effectiveness of the new solution.