采用SST k-ω湍流模型对离心泵内部流场进行了三维非定常数值模拟,分析了不同时刻叶片与隔舌相对位置对模型泵瞬时性能及压力脉动的影响。利用数理统计学原理和时-频域数据处理方法对流场内监测点的压力脉动进行分析。结果显示:叶片与隔舌间的动静干涉引起模型泵瞬时性能呈周期性变化,瞬时扬程与瞬时效率波动较大而瞬时轴功率波动值较小;改进特定时刻叶片与隔舌相对位置处泵的最低瞬时性能是提高其总体性能的一条途径;隔舌及叶片附近均是较强的脉动源,脉动最强的部位不在隔舌顶部而是向螺旋线方向偏移;叶片通过频率是压力脉动的主要频率。
The three - dimensional unsteady flow field in a centrifugal pump is numerically simulated, where SST k - co turbulence model is adopted to solve Navier - Stockes equations. The detailed influence from different impeller - volute tongue location to instantaneous pump performance and total pressure pulsation are presented. Pulsation of the static pressure is discussed after using amplitude and time - frequency domain analysis methods. The results show that the instantaneous values of head coefficient and efficiency showing a periodic change highly depend on the interaction between blade and volute tongue, yet the power coefficient is almost invariable. It is a way to improve overall pump performance by improving the lowest instantaneous performance at particular time. Main pressure pulsation source are distributed near the cut - water and blades, especially the strongest fluctuation do not locate at the top of volute tongue, but migrate along with the spiral direction. Blade passing frequency is the main form of the pressure pulsation.