水泵水轮机泵工况空化诱导流动失稳机理  

Cavitation induced flow instability mechanism of pumpturbine under pump conditions

作　　者：阮辉 郭鹏程[2] 余龙[2] 周创辉 晁文雄 李祥阳 RUAN Hui;GUO Pengcheng;YU Long;ZHOU Chuanghui;CHAO Wenxiong;LI Xiangyang(Special Pump System Technology National and Local Joint Engineering Research Center,Xi′an Aeronautical University,Xi′an,Shannxi 710077,China;Institute of Water Resources and Hydro-electric Engineering,Xi′an University of Technology,Xi′an,Shannxi 710048,China)

机构地区：[1]西安航空学院特种泵系统技术国家地方联合工程研究中心,陕西西安710077 [2]西安理工大学水利水电学院,陕西西安710048

出　　处：《排灌机械工程学报》2023年第8期779-786,共8页Journal of Drainage and Irrigation Machinery Engineering

基　　金：陕西省自然科学基金资助项目(2021JM-525)。

摘　　要：针对水泵水轮机泵工况空化特性及其引起的流动失稳问题,采用空化流动数值模拟分析和模型空化试验相结合的方法,获得不同流量水泵工况下水泵水轮机的空化特性,探明了不同空化系数泵工况下水泵水轮机内部湍流场的结构特征,阐明了水泵水轮机内部空化与旋涡的关联特性,揭示了水泵水轮机空化流动特征及其与主流干涉失稳机理.研究结果表明,不同流量和空化系数的泵工况下,水泵水轮机空化发生的位置及剧烈程度存在明显差异.小流量工况下,叶片低压边吸力面的剧烈空化引起的流动分离干扰主流场流动,产生大面积脱流和涡流,使得水泵水轮机的效率降低;最优工况和大流量工况下,相邻叶片不同位置的空化引起的脱流一旦产生相互干扰,将在转轮叶道内形成大范围的回流和涡流,导致水泵水轮机的效率和扬程大幅度降低.To research into the cavitation characteristics of pump turbine and induced flow instability,a method of cavitation mumerical simulation in combination with model tests was used.The cavitation characteristics of pump turbine under pump conditions with different flow rates were obtained,the structural characteristics of turbulent field in pump tubine under pump condition with diferent cavitation coefficients were explored,the correlation between cavitation and vortex in pump turbine was clarified,and the cavitation flow characteristics of pump turbine and its mechanism of interference instability with mainstream were revealed.The results show that under pump conditions with different flow rates and cavitation cofficients,the location and intensity of cavitation oceurs with obvious differences.Under pump condition with small flow rate,the flow separation caused by,the intense cavitation on the suction surface at the low-pressure side of the blade interferes with the main flow,and large areas of decurrent and eddy current are produced,which reduces the eficiency of the pump tubine.Under optimal operating condition and large flow rate condition,once the flow separation caused by cavitation at different positions of adjacent blades interferes with each other,a large range of backflow and eddy currents will be formed in the runner blade passage,resulting in a significant reduction in the effciency and head of the pump turbine.

关 键 词：水泵水轮机 流动失稳机理 空化 模型试验 

分 类 号：S277.9[农业科学—农业水土工程] TK734[农业科学—农业工程]