基于改进灰狼算法的磁悬浮离心泵优化设计

Optimization of Magnetic Levitation Centrifugal Pumps Based on Improved Gray Wolf Optimizer

摘要:

为了提高磁悬浮离心泵的水力效率，选取某型号的磁悬浮离心泵为研究对象，在流量15L/min、转速6000r/min的工况下以泵的效率最大值作为优化目标，基于泵的基本方程采用Plackett-Burman试验设计筛选出对效率影响最为显著几何参数，最终选出叶片进口边交点节圆直径、节圆切线与工作面切线的夹角、叶片工作面型线半径、叶片背面型线半径、前盖板轴面投影线与竖直方向的夹角作为优化变量。采用最优拉丁超立方设计方法设计了50组试验方案，并结合数值模拟的方法计算出相应的扬程和效率，引入RBF神经网络进行训练得到优化变量与优化目标之间的近似模型，最后利用改进后的灰狼算法进行寻优。结果表明：经过优化，磁悬浮离心泵的扬程提高了0.06m，水力效率提高了0.56个百分点，同时流量-扬程曲线变得更加平滑，使泵的运行更加稳定；优化后叶轮流道变宽，流道内的压力梯度变小，漩涡在径向收缩，叶片工作面的漩涡几乎消失，流动状况有所改善；叶轮流道内湍动能分布更加合理，同时低湍动能区域增加，流动损失减少，叶片做功能力提高，水力效率也因此提高。

Abstract:

In order to improve the hydraulic efficiency of the magnetic levitation centrifugal pump, a certain type of magnetic levitation centrifugal pump was selected as research object, and the maximum value of the pump efficiency was taken as the optimization target under the working condition of flow rate of 15L/min and rotational speed of 6000r/min, and the most significant geometrical parameter impact on the efficiency was screened out by using the Plackett-Burman experimental design based on the basic equations of the pump and the inlet side of the blade was selected to be the intersection point of inlet side. Finally, the intersection point of the inlet side of the blade was selected as the optimization variable, which included the diameter of the pitch circle, the angle between the tangent line of the pitch circle and the tangent line of the working surface, the radius of the working surface of the blade, the radius of the backside of the blade, and the angle between the projection line of the axial surface of the front cover plate and the vertical direction. The optimal Latin hypercube design method was used to design 50 groups of test schemes, and the corresponding head and efficiency values were calculated by combining with numerical simulation, RBF neural network was introduced for training to get the approximation model between the optimization variables and optimization objectives, and finally the improved GWO was used for optimization searching. The results showed that after optimization, the head of the magnetic levitation centrifugal pump was increased by 0.06m, the hydraulic efficiency was increased by 0.56 percentage points, and at the same time, the flow-head curve became smoother, which made the operation of the pump more stable;the impeller channel became wider, and the pressure gradient inside the channel became smaller, the vortex shrank in the radial direction, and the vortex in the working surface of the blades almost disappeared;the distribution of the turbulent kinetic energy inside the impeller channel was more reasonable, and at the same time, the low turbulence kinetic energy distribution was more reasonable. The distribution of turbulent kinetic energy in the impeller channel was more reasonable, and at the same time, the area of low turbulent kinetic energy was increased, the flow loss was reduced, thus the work capacity of the blades was improved, as a result, the hydraulic efficiency was improved.