超大型离心泵内脉动压力特性研究

Characteristics of Fluctuating Pressure in Super Size Centrifugal Pumps

采用大涡模拟方法对某超大型明蜗壳立式离心泵进行全流道三维非定常数值分析,得到了运行状态下的泵内流场脉动压力特性。研究结果表明:泵内流态复杂,脉动压力的频率由泵的转动频率、叶轮叶片数和固定导叶数等多因素耦合决定;脉动压力幅值从蜗舌至蜗壳出口沿蜗壳周向先逐渐减少然后再逐渐增大,从叶轮至蜗壳沿泵径向快速减小,扩散段脉动压力变化不明显。

By means of adopting large eddy simulation, the whole flow passage of the pump with 3-D unsteady numerical study methods was analyzed and features of fluctuation pressure of flow field inside the pump in operating states was got. The result showed that flow pattern inside the pump was complex. The frequency of fluctuation pressure was determined by rotation frequency of the pump, impeller vane number and the number of fixed guide vanes, etc. Fluctuating pressure amplitude first gradually reduced and then gradually increased along the volute weeks from the snail tongue to the volute outlet. It decreased rapidly along pumps radial from the impeller to the volute, but not changed significantly in the diffusion segment. The research method and conclusions have practical value for insuring safety operation of the super size centrifugal pump.