竖井贯流泵装置压力脉动数值分析

Pressure Fluctuation Numerical Analysis of Shaft Tubular Pump Device

为深入研究竖井贯流泵站机组振动产生的机理,以国内某大型竖井贯流泵站泵装置模型为例,基于ANSYS-CFX商用数值模拟软件,在不同工况下利用N-S方程和标准κ-ε方程模型分别计算全流道三维非定常湍流。结果表明,采样频率影响压力脉动特性预测、泵装置内压力脉动的主频率为叶片通过频率、在各工况下叶轮进口压力脉动从轮毂到轮缘逐渐增大、运行工况偏离设计工况时脉动幅度变大、水泵叶轮进口前的压力脉动沿轴向向前至0.5倍转轮直径处消失。通过对比泵站模型试验结果与数值模拟结果,验证了本文数值模拟结果的有效性。

To search the mechanism of the vibration of shaft tubular pumping station, it takes the model pump set of a domestic large shaft tubular pumping station as an research object. Based on ANSYS-CFX software, Navier-Stokers e- quation and standard ^-~ turbulence model were used to simulate three-dimensional unsteady flow of the whole flow chan- nel under different working conditions. The results show that the sampling frequency has impact on the pressure fluctua- tion prediction. The dominant frequency of pump set is the blade passing frequency. The pressure fluctuation at the im- peller inlet increases from hub to shroud gradually under different working conditions. The pressure amplitude changes greatly when the working condition deviate the design condition. The pressure fluctuation phenomenon in front of the inlet disappears at the 0.5D far from the inlet. Model test of pumping station is compared with the result of numerical simula- tion, it verifies the effectiveness of the proposed method.