自吸泵内部流场的数值模拟及性能预测

基于雷诺时均Navier-Stokes方程和标准k-ε湍流模型,应用三维无结构四面体网格及SIMPLEC算法建立自吸泵内部流场的数值模型,利用计算流体力学软件Fluent对设计工况及多个非设计工况下自吸喷灌泵叶轮和蜗壳的三维不可压缩湍流流场进行了数值模拟,得到其内部流场的速度分布和压力分布情况,揭示了泵自吸过程中流体的运动规律,最后预估该泵的扬程及效率并与试验值进行对比分析.结果表明,在相同半径处,叶片工作面压力比背面压力大;在回流孔处存在较大的压力梯度和速度梯度,并且由于分离室边壁的影响形成了大小不同的旋涡;数值模拟性能曲线与试验曲线基本一致.

Numerical simulation of interior flow and performance prediction for self-priming pump

The numerical simulation of interior flow field in self-priming pump under different working conditions was conducted on the platform of Fluent.Three-dimensional non-structural tetrahedral mesh and the SIMPLEC method were applied according to the time-averaged Navier-Stokes equation and standard k-ε turbulent model.The velocity and pressure distributions of the interior flow field of volute and impeller were obtained and analyzed,which revealed the flow principle inside the pump in the process of self-priming.Both the head and efficiency of the pump predicted were compared with that of tested.The results show that the pressure on blade pressure side is larger than that on the suction one at the same radius,both high pressure gradient and high velocity gradient appear at the reflux hole,and vortices with different sizes are formed due to the influence of separation chamber sidewall.The characteristic performance curves by numerical simulation basically agree with that by test.