混流泵出水歧管流场分析及结构改进

Analyzing Water Flowin Manifold of Mixing-flow Pump and the Method to Improve Its Structure

针对排灌作业混流泵出水歧管头部涡旋严重,歧管侧面出水流道内存在较为严重的涡旋及局部脱流问题,提出了相应的结构改进方案,以提高侧面出口断面速度分布均匀性、减小流道的水力损失为目标,将建立的参数化三维模型导入至IECM中完成网格的划分,利用CFD三维湍流数值模型进行有限体积法分析,逐步改进出水歧管流道的结构。结果表明,管道的连接圆滑过渡程度、岔管的夹角会影响流场的分布,通过这2个关键因素的改进来提高出水歧管的流道性能,从而减小水力损失。

This paper proposed a methodto modify the structure of mixing-flow pump so as to resolve the prob- lem of formation of vortex near the headof its manifold and partial desorption from the outlet of its manifold in at- tempts to improve flow-distribution uniformity and reduce hydraulic head loss. The three-dimensional structure of the manifold was first discretized into grid network using IECM, and the turbulent water flow through it was then simulated using CFD model; the simulated results were used to help improve manifold structure. The results showed that a smooth transition between the connection pipe and the angle of branch pipe influences the distribu- tion of water flow field, and modifying their designs could improve the flow field in the outlet of the manifold and reduce hydraulic head loss.