多级离心泵多工况压力脉动数值模拟  

Numerical Simulation of Pressure Fluctuation for Multistage Centrifugal Pump Under Multiple Operating Conditions

作　　者：黄茜[1] 袁寿其[1] 方玉建[1] 张金凤[1] 张霞[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,江苏镇江212013

出　　处：《中国农村水利水电》2016年第10期191-195,共5页China Rural Water and Hydropower

基　　金：国家自然科学基金(51009072);江苏省优势学科资助

摘　　要：为了研究多级泵中叶轮和导叶的动静干涉现象,采用Ansys CFX软件对某一5级离心泵不同流量工况下非定常流动进行数值模拟,获得并分析了叶轮和导叶内4个典型位置的流动压力脉动分布特性。通过与外特性试验和振动试验结果的对比,验证了数值模拟的可信性。结果表明:各监测点脉动主频560 Hz左右,为2倍叶频处,且振动幅值较大,动静干涉现象强烈;叶轮与导叶交界面的压力脉动强度最大;导叶内压力脉动受叶轮的影响,离叶轮出口越远,压力脉动幅值越小;导叶内在叶频处存在较大峰值,说明叶频是其出口压力脉动的主要成分,流量越小,脉动强度越大。通过掌握压力脉动分布特性,能够为多工况运行的低压力脉动多级离心泵水力设计提供重要的理论依据。In order to investigate the rotor-stator interaction （RSI） between impeller and guide vane for multistage centrifugal pump. Ansys CFX software is adopted to simulate the unsteady flow under multiple operating conditions for a five-stage centrifugal pump, and the pressure fluctuations at monitoring points distributing in four different locations in both the impeller and guide vane passages are obtained under different flow rates. The numerical results are partially confirmed by the experimental results. In general, the fluctuating frequency of each monitoring points is about 560 Hz, which is equal to two times of the blades＂ passing frequency, and the vibration amplitude is quite large, which means the rotor-stator interaction is strong. The pressure fluctuation around the interface between the impeller and guide vane is maximum, the pressure fluctuation in the guide vane is influenced by the impeller obviously, and the monitoring point away from the exit of the impeller farther, the amplitude of pressure fluctuation is smaller. Seen from the frequency spectrogram of the guide vane, the high peak lies at its blades＂ passing frequency, which shows that the dominant frequency in the guide vane is the blades＂ passing frequency. The fluctuation amplitude is amplified, especially at the lower flow rate. The pres- sure fluctuation distribution can be an important theoretical basis for designing low pressure fluctuation multistage centrifugal pumps under multiple operating conditions.

关 键 词：多级离心泵 非定常流动 压力脉动 数值模拟 多工况 

分 类 号：TV93[水利工程—水利水电工程] S277.92[农业科学—农业水土工程]