高水头水泵水轮机空化特性分析  

An Analysis of Cavitation Characteristics of High Head Pump Turbine with Splitter Blades

作　　者：宁楠 李萍 NING Nan;LI Ping(School of Energy and Power Engineering, Xihua University, Chengdu 610039, China)

机构地区：[1]西华大学能源与动力工程学院

出　　处：《中国农村水利水电》2019年第6期116-120,124,共6页China Rural Water and Hydropower

基　　金：四川省科技计划重点项目(2017GZ0053,2017JY0047,2017NZ0031);国家自然科学基金项目(51379179)

摘　　要：为探究多工况下水泵水轮机空化特性,选取5个典型工况,采用Rayleigh-Plesset空化模型对水泵水轮机进行三维定常数值模拟。结果表明:在水轮机工况,伴随空化数减小,大、中流量下长叶片吸力面靠近下环根部的空化程度逐渐加重,沿下环线形成类似鱼尾拖拽区,而小流量空化区域则沿长叶片吸力面出口的中部向来流方向蔓延。在水泵高、低扬程工况,空化区域位于长叶片不同部位,空化严重时易引起叶片表面流体脱流及流道漩涡现象,导致扬程急剧下降。In order to investigate the cavitation characteristics of pump turbine with splitter blades under multi-condition,three turbine and two pump operating conditions are selected. The Rayleigh-Plesset cavitation model is used to simulate the three-dimensional constant values of a pump turbine. The calculated results are in good agreement with the measured data of the flow field,and the variation of energy characteristics and cavitation performance under different working conditions are predicted. The results show that in the turbine mode,as the cavitation number decreases,the degree of cavitation of the root of suction surface of long blade near the lower ring increases gradually under large and medium flow conditions,and a dragging area similar to fish tail is formed along the lower ring line,the cavitation area spreads to the inlet along the middle of the outlet of the suction surface of the long blade,which is significantly enlarged. Under the low head condition of the pump mode,cavitation mainly occurs on the long blade pressure surface. However,the suction surface of the long blade is susceptible to serious cavitation at the high head condition,and the front edge of the pressure is only slightly cavitated. When cavitation is serious,it is easy to cause fluid flow off the surface of the blade and vortex in the flow channel and a sharp drop in head.

关 键 词：水泵水轮机 长短叶片转轮 多工况 空化数 空化特性 

分 类 号：TV136.1[水利工程—水力学及河流动力学] TK73[交通运输工程—轮机工程]