为了揭示阀门开度对泵作透平循环系统启动特性的影响，本文对泵作透平循环系统在五种阀门开度情形下进行了三维黏度非定常流动的数值计算，得到了启动过程中各个过流部件的外特性和内流特性，同时还借助于熵产分析和Q 准则深入分析了管路系统内各部件的能量损失情况。结果表明：随着阀门开度增大，泵作透平叶轮流域与阀门流域内涡与熵产的分布逐渐增加，即能量损失增大。泵作透平进出口压降、流量、扬程均随着阀门的增大而增大，但阀门开度大小无线性关系。

In order to reveal the influence of valve opening on the start-up characteristics of the pump as turbine circulation system, this paper numerically calculates the three-dimensional viscosity non-constant flow of the pump as turbine circulation system under five valve openings and obtains the external and internal flow characteristics of each overflow component during the start-up process, and also analyzes the energy loss of each component in the piping system in depth with the help of entropy production analysis and Q criterion. The results show that as the valve opening increases, the distribution of vortex and entropy production in the impeller domain and valve domain of the pump turbine gradually increases, i.e. the energy loss increases. The pressure drop, flow rate and head of pump turbine inlet and outlet all increase with the increase of valve, but there is no linear relationship between the size of valve opening.