水轮机补气条件下压力脉动的数值分析  

Numerical simulation and analysis of pressure pulsation in Francis hydraulic turbine with air admission

作　　者：钱忠东[1] 郑彪[1] 杨建东[1] 吴玉林[2] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072 [2]清华大学热能工程系,北京100084

出　　处：《水力发电学报》2008年第4期126-129,134,共5页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金项目(50609020);湖北省自然科学基金青年杰出人才项目(2006ABB040);水资源与水电工程科学国家重点实验室开放研究基金资助项目(2004C006)

摘　　要：本文对某电站原型混流式水轮机进行三维非定常多相湍流模拟,对大轴中心孔补气前后水轮机各过流部件内的压力脉动进行计算,并与试验结果相比较,探讨了水轮机补气减振的机理。分析结果表明:大轴补气能够减小尾水管断面的压差,从而降低尾水管低频压力脉动的振幅,但对振动频率影响不明显;补气孔入口与转轮之间存在动静干扰,在转轮区域形成新的振源,增强了转轮前的中频压力脉动。In this paper, the three-dimensional unsteady multiphase flow is simulated in the whole passage of Francis hydraulic turbine. The pressure pulsation is calculated and compared with the experimental data at positions in the draft tube, in front of runner, guide vanes and in the inlet of the spiral case. The relationship between pressure pulsation in the whole passage and air admission is analyzed. The computational results show that air admission from spindle hole decreases the pressure difference in the horizontal section of draft tube, which decreases the amplitude of low-frequency pressure pulsation in the draft tube; the interaction between the air inlet and the runner increases the middle-frequency pressure pulsation in front of the runner.

关 键 词：水力机械 混流式水轮机 补气 压力脉动 数值模拟 

分 类 号：TK733.1[交通运输工程—轮机工程]