高水头电站岔管过渡段水力优化研究

Research on the Hydraulic Optimization of Transition Section of Bifurcated Pipe in High Water Head Hydropower Station

高水头电站岔管处的水流流动较一般水头更为复杂,所产生的局部损失较大。为此,以高水头电站岔管过渡段的优化为研究对象,建立了不同岔管过渡段的三维数值计算模型,数值模拟了最大发电流量下不同锥角角度过渡管的岔管内流速和压力分布,分析计算了不同工况下的水头损失系数大小。结果表明:随着锥形过渡管锥角角度的增大,岔管处的回流区和相对低压区有效减小,局部损失系数也相对减小,流场分布更加均匀。

The flow of water in the bifurcated pipe of high water head hydropower station is more complicated than the stations with low water head, and the local head loss in bifurcated pipe is also larger. To this end, the optimization of transition section of bifurcated pipe in high water head hydropower station is taken as the research object, and the three-dimensional numerical models for different transition sections are established. The velocity and pressure distributions in the bifurcated pipes with different taper angle of transition pipes under the maximum power flow are simulated numerically, and the head loss coefficients under different conditions are also analyzed and calculated. The results show that, with the increase of cone angle of tapered transition tube, the backflow area and relative low pressure area at the bifurcation pipe can be effectively reduced, the local loss coefficient is also relatively reduced, and the flow field distribution is more uniform.