为了研究时序效应对导叶式离心泵内部非定常压力脉动的影响，基于雷诺时均(Reynolds averaged Navier-Stokes, RANS)方程，在0.6Qd、1.62Qd两个非设计工况下，应用SST k-ω湍流模型对导叶在一个栅距内的5个不同时序位置下泵内部流动进行三维非定常数值计算，得到导叶和蜗壳流道内压力脉度强度分布随不同导叶时序位置的变化规律，结果表明，导叶时序效应对叶轮与导叶的动静干涉引起的压力脉动强度影响较明显；在导叶靠近进口的吸力面区域和导叶喉部区域存在着较大的压力脉动强度；压力脉动强度沿着导叶流道向下游传播并逐渐减弱；导叶时序效应对蜗壳平面的压力脉动强度影响非常明显，压力脉动强度呈现不规律分布；当在小流量0.6Qd工况时，当导叶时序位置为C3时，导叶内压力脉动强度最大值为0.44，而当导叶时序位置为C2和C4时，压力脉动强度最大值分别为0.24和0.22；当在大流量1.62Qd工况时，当时序位置为C2时，压力脉动强度最大值为0.87，而当时序位置为C1和C4时，压力脉动强度最大值为分别为0.72和0.77；在非设计工况下，蜗壳内的压力脉动强度相对导叶的压力脉强度较弱。C4时序位置能减小余热排出泵运行中的压力脉动强度，从而提高泵的稳定性，为导叶的安装位置提供参考。

In order to study the clocking effect on the unsteady pressure fluctuations in the centrifugal pump with a vaned diffuser, the three-dimensional unsteady numerical simulations are undertaken to analyze the inner flow characteristics with 5 different positions of diffuser by solving the RANS equations with SST k-ω turbulence model under 60% and 162% of the design conditions. The pressure fluctuation intensity distributions caused by the clocking effect in the diffuser and the volute are obtained. The results show that the clocking effect of diffuser on pressure fluctuation intensity due to the rotor-stator interaction is obvious. In the diffuser, the highest pressure fluctuation intensities occur at the throat area and the pressure side near the leading edge. The pressure fluctuation intensity propagates and weakens along the diffuser passage. Pressure fluctuation intensity distribution due to the clocking effect is irregular significantly. Under the partload condition in the diffuser, when the diffuser position is C3, the maximum value of the pressure fluctuation intensity is 0.44; when the diffuser positions are C2 and C4, the maximum values are 0.24 and 0.22, respectively. Under the overload condition in the diffuser, when the diffuser position is C2, the maximum value of the pressure fluctuation intensity is 0.87; when the diffuser positions are C1 and C4, the maximum values are 0.72 and 0.77, respectively. The pressure fluctuation intensity is much smaller than that in the diffuser under the partload and overload operating conditions. The relative position C4 can decrease the pressure fluctuation intensity and the result can provide a reference to the setting relative position of the diffuser to the volute.