用正交法研究短叶片对水轮机空化性能的影响

为了研究短叶片各设计参数对混流式水轮机空化性能的影响,选取短叶片数、长短叶片包角比值以及短叶片周向偏置角3因素,制定了L16(43)正交试验方案,对每个试验方案进行数值模拟,得出影响空化性能的各因素主次顺序;水轮机性能最优情况下,短叶片的最佳参数为:叶片数为11,长短叶片包角比值为0.65,周向偏置角为8°。对最佳配置方案在设计工况点的数值模拟结果分析表明:其空化性能优于该型号常规转轮正常运行时的空化性能。

Study on Splitter Blades' Effects on Cavitation Performance of Turbine by Orthogonal Technology

In order to study the influence of splitter blade's parameters on the cavitation performance of Francis turbine,a L16(43) orthogonal experiment is designed with three factors and four values.These factors are the numbers of short-blade,the wrap angle ratio of long blade and short blade,and the circumferential offset angle of short blade.By the range analysis of each orthogonal designing scheme's numerical simulation results,the primary and secondary sequence affecting the turbine performance of three main factors is obtained.The best design scheme is that the number of short-blade is 11,the circumferential offset angle of short blade is 8 degrees,and the length ratio of long blade and short blade is 0.65 when the turbine performance is most superior.The analysis of numerical simulation results at point of design condition shows that its cavitation performance surpasses that of the hydraulic turbine with convertional impeller when it is normally operating.