Numerical Investigation of Pressure Fluctuation in Centrifugal Pump Volute Based on SAS Model and Experimental Validation
Numerical Investigation of Pressure Fluctuation in Centrifugal Pump Volute Based on SAS Model and Experimental Validation
复制标题
基于SAS模型的离心泵蜗壳压力脉动数值研究及实验验证
DOI：
10.1155/2014/972081
复制
发表时间：
2014-01-01
影响因子：
2.1
通讯作者：
Bois, Gerard
中科院分区：
文献类型：
--
作者：
Si, Qiaorui;Yuan, Jianping;Bois, Gerard
本文采用数值计算和实验相结合的方法，对单吸蜗壳式离心泵，特别是蜗壳内的压力脉动进行了研究。本文采用一种新型的混合雷诺平均N-S/大涡模拟（简称SAS）模型对非定常流场进行了数值模拟。采用统计分析的方法，对蜗壳流道内的压力脉动强度分布进行了研究。为了验证数值模拟结果的正确性，搭建了蜗壳中部压力脉动测量试验台，在蜗壳壁面安装了8个瞬态压力传感器。结果表明，SAS模型能较准确地预测离心泵内部流场。作用在叶轮上的径向力与叶片数呈星星分布。压力脉动强度在舌部附近最强，在泵壳内呈不规则分布。由于蜗壳可以消除叶轮排出液体的旋转运动，压力脉动在蜗壳横截面上呈对称分布。叶片通过频率及其倍数是蜗壳内各监测点的主频，当蜗壳在非设计工况下运行时，特别是在小流量工况下，低频脉动，尤其是轴部件的低频脉动增大。其原因是在非设计工况下涡波增强，对轴产生影响，并在频域中表现在轴部件上。
This paper presents an investigation of pressure fluctuation of a single-suction volute-type centrifugal pump, particularly volute casing, by using numerical and experimental methods. A new type of hybrid Reynolds-averaged Navier-Stokes/Large Eddy Simulation, referred to as the shear stress transport-scale-adaptive simulation (SAS) model, is employed to study the unsteady flow. Statistical analysis method is adopted to show the pressure fluctuation intensity distribution in the volute channel. A test rig for pressure pulsation measurement is built to validate the numerical simulation results using eight transient pressure sensors in the middle section of the volute wall. Results show that the SAS model can accurately predict the inner flow field of centrifugal pumps. Radial force acting on the impeller presents a star distribution related to the blade number. Pressure fluctuation intensity is strongest near the tongue and shows irregular distribution in the pump casing. Pressure fluctuation is distributed symmetrically at the cross-section of the volute casing because the volute can eliminate the rotational movement of the liquid discharged from the impeller. Blade passing frequency and its multiples indicate the dominant frequency of the monitoring points within the volute, and the low-frequency pulsation, particularly in the shaft component, increases when it operates at off-design condition, particularly with a small flow rate. The reason is that the vortex wave is enhanced at the off-design condition, which has an effect on the axle and is presented in the shaft component in the frequency domain.