潜水轴流泵叶轮掠角的优化设计与试验

Optimization Design and Experiment of Leaned Angle of Submersible Axial-flow Pump Impeller

采用CFD技术与优化算法相结合的方法对潜水轴流泵叶轮进行优化设计。以叶轮水力效率最大为优化目标,叶轮掠角为优化变量,对其进行优化设计并分析了掠角对潜水轴流泵性能的影响。首先对原始叶轮进行参数化处理,为优化设计提供优化变量;然后,在-40°~40°的优化范围内采用拉丁超立方实验设计方法进行空间抽样,应用遗传算法与神经网络相结合的优化算法,得到最优叶轮模型。研究结果表明:数值模拟与试验数据吻合较好,能够准确预测潜水轴流泵的性能;在优化范围内,掠角-扬程曲线、掠角-效率曲线呈抛物线状变化趋势,均存在极大值;后掠角度为+5.57°时,叶片性能最佳,叶轮效率较原始模型提高了3.61%;在同一掠角度下,后掠叶片的效率和扬程均高于前掠叶片;在设计工况点,优化后的泵效率比原始泵提升了2.6%;带最优叶轮泵的导叶损失比原始泵的导叶损失降低4.41%,导叶与叶轮的匹配性得到了改善。

A submersible axial-flow pump impeller was optimized by the CFD technology and optimization algorithm.With the maximization of hydraulic efficiency of impeller as the optimization object and the leaned angle of the impeller as the optimization variable,optimization design was carried out on it and the influence of leaned blades on the flow performance of the submersible axial-flow pump was analyzed.First,the original blade model was parameterized in order to provide optimized variables for optimization design.Second,Latin hypercube experimental design method was chosen to carry out spatial sampling in the optimum range from-40 deg to 40 deg.The optimal impeller model was obtained by applying the optimization algorithm that combines genetic algorithm and the artificial neural network.The study results show that the results of the numerical calculation are in good agreement with the experiment data,and can accurately predict the performance of the submersible axial-flow pump;In the optimization range,the leaned angle-head curve and the leaned angle-efficiency curve present a parabolic change trend,and there is a maximum value for both of them;The optimal impeller model was obtained when the leaned angle was+5.57 deg.Compared with the original model,the hydraulic efficiency was increased by 3.61%at the design point.At the same leaned angle,both the head and efficiency of backward-leaned blades were better than those of the forward-leaned one.The pump efficiency after optimization was increased by 2.6%at the design point against the original pump.The hydraulic loss of the impeller pump with optimal blades was reduced by 4.41%compared to that of original pump.The matching of blades and impeller was improved.