HL741水轮机增容改造及数值模拟研究

Study on the Capacity⁃Increasing Improvement and Numerical Simulation of HL741 Hydroturbine

根据古浪堤电站HL741水轮机增容改造的需求,对诸多较优模型转轮的分析对比后,拟定选用HLA232叶片并稍加改型,同时为增大过流能力解决汛期转轮流道易堵塞的问题,最终决定采用在此基础上减少一个叶片后制造新转轮的方案对原水轮机进行改造。借助数值试验平台对改造前后的水轮机进行全流道三维流场数值计算及性能预测,分析计算结果并给出了水轮机改造前后的水动力学特性差异。改造后水轮机蜗壳及导水部件内流动与改造前差异很小,水力性能没有下降;转轮叶片中水流的流态分布合理,空蚀性能提升;尾水管中水流平稳顺畅。在以后的改造工程中可用HLA232转轮经适当修型以匹配原转轮室结构后替代HL741转轮。

According to the capacity⁃increasing and transformation needs of HL741 turbine of Gulangdi Power Station and after the analysis and comparison of many excellent model runners,the slightly modified HLA232 blade was selected,at the same time it increased the flow ca⁃pacity to solve the problem of runner was easily to be blocked in flood season,ultimately decided to use this scheme and reduced a blade to manufacture new turbine runner to achieve capacity⁃increasing.By means of numerical simulation to calculate three⁃dimensional flow field of the whole hydraulic turbine before and after the modification and predict performance.The results of the calculation were analyzed and the difference of hydrodynamic characteristics of the water turbine before and after reform was given.The flow distribution of the overflow parts of the water turbine before and after the transformation was analyzed and compared.The overall hydraulic performance of the reformed turbine was predicted.