离心泵叶轮非设计工况下内部湍流流场的模拟

Numerical simulation of flow in centrifugal pump impeller at off-design conditions

采用ANSYS CFX11.0软件、标准k-ε湍流模型及SST湍流模型封闭雷诺平均方程,对低比转速离心泵叶轮在非设计工况下内部流场进行了三维定常湍流数值模拟,获取了离心泵叶轮内部流场结构,此两种模型所计算出的内部流场图案与参考文献中的PIV试验结果以及大涡模拟(LES)的计算结果基本一致,获得了文献中出现的'交替失速'这一特殊的流动现象.此外,对不同直径处将本计算所得到的速度轮廓的形态与文献中的PIV及LES结果进行了比较,结果显示采用标准k-ε湍流模型及SST湍流模型能够对离心泵内部流动进行比较精确的模拟,但是在局部上与PIV试验结果有一定的偏差,并进行了初步分析,但仍需要对湍流模型进行进一步的探索和研究.

Based on ANSYS CFX 11.0, the three dimensional numerical simulations of flow in a low spe- cific speed pump impeller under off-design condition are performed using the RANS equations with turbulence model of standard k - ε and SST. Both two models captured the ＂alternative stall＂ phenomena as in the reference paper. The comparison of velocity profile has been taken at different diameters for this computations, PIV and LES results in reference paper. It resumes that using standard k -ε and SST can simulate the flow in a low specific speed pump impeller under off-design condition accurately, but there are some errors compared with PIV measurements and LES results of the flow field in the impeller. The models need further study.