混流式水轮机转轮优化设计的空化流计算  

Cavitation Simulation of Francis Turbine Runner for Hydraulic Optimization Design

作　　者：王磊[1] 常近时[1] 

机构地区：[1]中国农业大学水利与土木工程学院,北京100083

出　　处：《农业机械学报》2009年第9期98-102,共5页Transactions of the Chinese Society for Agricultural Machinery

摘　　要：采用求解时均N-S方程,结合气液质量输运方程的两相流方法,在水轮机优化设计中进行转轮的空化流场分析。结果显示:在高水头下适当增加叶片包角,延长出水边,数值计算效率为94.7%,明显高于改型前的93.4%;叶片压力分布更为均匀,最优工况点的临界空化系数也低于改型前的0.03,空穴区域减小,转轮的空化性能得到改善。计算结果与实验结果相符,为转轮的再优化设计提供了参考依据。The simulation of cavitating flows in hydraulic runner for the hydraulic optimal design was presented by using the two-phase flow method through the solution of the time-average Navier-Stokes equations based on the mass transport equation.The results show that the efficiency apparently increases from 93.4% to 94.7% when the wrap angle of the blade enlarges and the trailing edges of the blade extend.The pressure on the blades is well distributed and the critical cavitation coefficient at optimum operating condition is lower than unmodified,0.03, and the cavity domain are also decreased.Finally,the cavitation performance of runner is improved.The computational results,which agree with experimental data,provide a correct direction for further optimal design for the runner.

关 键 词：水轮机 优化设计 空化流 

分 类 号：TK734[交通运输工程—轮机工程] TH318[动力工程及工程热物理—流体机械及工程]