【摘要】 对新疆夏特水电站拟采用的HLA351-LJ-275型水轮机在小流量工况下导叶端面间隙流动特性进行了三维数值模拟,尤其是空化流。结果表明,随着端面间隙增大,间隙处流速增加,单流道内压力分布变均匀。端面间隙由0.5逐渐增大至1.5 mm过程中,空化区域和气泡体积分数增大。端面间隙大于1.5 mm后,随着端面间隙进一步增大,活动导叶上空化区域和气泡体积分数减小,并通过试验给出1.5 mm的导叶端面空蚀情况,研究结果对高水头水电站水轮机导水机构设计和安装具有指导意义。更多还原

【Abstract】 In this study,three-dimensional numerical simulation is carried out for the flow characteristics of HLA351-LJ-275 turbine in the guide vane end clearance of Xiate Hydropower Station in Xinjiang under the condition of small flow rates,especially the cavitation flow. The results show that the pressure distribution in a single flow channel becomes uniform with the increase in the end clearance and the increase in the velocity at the clearance. In gradually increasing the end face clearance from 0.5 to 1.5 mm,the cavitation area increases and the bubble volume fraction increases. When the end face clearance is more than 1.5 mm,as the end face clearance further increases,the area over the active guide vane decreases,and the bubble volume fraction decreases. The cavitation erosion condition of guide vane end surface of 1.5 mm is given through the test. The research results are of guiding significance for the design and installation of water guide mechanism of turbine in high head hydropower stations.更多还原