S型弯管对双向轴伸泵性能及稳定性的影响

Effects of S-shaped Elbow in Bidirectional Shaft Extension Pump on the Performance and Stability

为了探究双向轴伸泵S型弯管对水泵装置性能及稳定性的影响,为双向泵的优化提供新的思路,本文通过稳态、非稳态的CFD计算及模型试验验证,将双向泵S型弯管按中心线圆弧半径比值b的不同分为四个方案,系统的分析比较了b值对水泵装置正反向工况的效率及压力脉动等因素的影响,最后得出当b值为0.75时水泵装置性能及稳定性较好。通过单向流固耦合的方法分析了S型弯管对叶片的影响,发现弯管小半径侧水流流量偏大,因此靠近该侧的部分叶片推动该部分水流时产生的应力也偏大,对叶轮稳定性造成影响,而当b值在0.75～1范围内时,叶片所受应力及变形较小。优选的方案与原方案相比在正反向工况下的效率及稳定性均有提升。

This paper is to explore how the S-shaped elbow of a bidirectional shaft extension pump effect the performance and stability of pump device and provide a new idea for the optimization of bidirectional pump. In this paper, the S-shaped elbow of bidirectional pump is divided into four schemes according to the ratio b of the center line’s radius. Through steady and unsteady CFD calculation and model test, the of effects of b value on the efficiency and stability in the forward and reverse condition of the pump device are analyzed and compared. It’s found that when b value is 0.75,the efficiency and stability of the pump device are better than the others. The influence of S-shaped elbow on blade was analyzed though one-way FSI numerical analysis and the result shows that the flow rate in the small radius side of the elbow is large, which causes the stress on the blades near this side to be relatively large. That may have an impact on the stability of the blades. When the b value is within the range of 0.75~1, the stress and deformation of the blade are relatively small. Compared with the original scheme, the efficiency and stability of the optimized scheme are both improved in the forward and reverse conditions.