基于响应面法的转向驱动桥空心半轴轻量化优化设计

Lightweight Optimization Design of the Hollow Half Shaft of Steering Drive Axles Based on Response Surface Method

提出了一种基于数值优化与有限元模拟相结合的汽车转向驱动桥空心半轴轻量化设计方法。以半轴各段的壁厚、长度和过渡角为设计变量,半轴质量最小化为优化目标,2阶约束模态频率和半轴花键末端圆角过渡处等效应力为约束条件,建立了半轴轻量优化模型。利用正交试验设计得到10个设计变量和3个水平的数值模拟试验组合。采用最小二乘法建立了响应面近似模型,并利用序列二次规划算法对模型进行了迭代优化。结果表明:轻量化优化后的变径全空心半轴质量比初始设计减少约16.7g,半轴2阶约束模态频率增加约0.6Hz,且半轴花键末端圆角过渡处和最小轴径处的等效应力值均低于半轴材料的抗扭强度。

A lightweight design method is proposed for the hollow half shaft of a vehicle steering drive axle based on the combination of numerical optimization and finite element simulation.An optimization model for the lightweighting of half shaft is set up with the thicknesses and lengths of different parts and the transitional angle of half shaft as design variables,minimizing the mass of half shaft as optimization objective,and the 2^（nd） order constrained mode frequency and the equivalent stress at the filleted corner of spline end as constraints.A numerical simulation experiment combination of ten design variables with three levels each is determined by using orthogonal experimental design,a response surface approximation model for the half shaft is established by using least squares method,and an iteration optimization is conducted on the model with sequential quadratic programming algorithm.The results show that after lightweighting optimization the mass of hollow half shaft reduces by 16.7g,the frequency of 2^（nd） order constrained mode increases by 0.6Hz,and the equivalent stresses at both the filleted corner of spline end and the location with smallest diameter are lower than the torsional strength of half shaft material.