Abstract: To solve the low efficiency and uncertainty problem of the wet drive axle housing structure in the traditional optimization, an optimal design method which combined the response surface model with reliability was proposed.Based on the finite element model of the full hydraulic wet drive axle housing and the Latin square test design scheme, the second-order response surface approximation model of the driving axle housing was constructed by the least square method. On the basis of the above,the reliability optimization model was established with the minimum maximum stress of the driving axle housing as the optimization objective and the geometric parameters of the driving axle housing as the design variables. The optimization results of a driving axle housing show that the maximum stress of the optimized axle housing is reduced by 10.91%, and the quality of axle housing is reduced by 10.93%.Under the condition of meeting the corresponding strength requirements, the quality of the axle housing can be effectively reduced to achieve the purpose of reliability design.

Key words: vehicle engineering, full hydraulic wet drive axle, axle housing, reliability optimization, response surface method, approximate model

摘要： 为解决湿式驱动桥壳结构传统优化中的低效性和不确定性，提出了一种将响应面模型与可靠性相结合的优化设计方法。该方法从建立全液压湿式驱动桥壳有限元模型出发，结合拉丁方试验设计方案，利用最小二乘法构建驱动桥壳的二阶响应面近似模型。在此基础上，以驱动桥壳最大应力最小为优化目标，以驱动桥壳结构几何参数为设计变量，建立可靠性优化模型。对某驱动桥壳的优化结果表明，优化后的桥壳最大应力降低了10.91%，桥壳质量降低了10.93%，在满足相应强度要求的条件下有效降低桥壳的质量，达到可靠性设计的目的。

关键词: 车辆工程, 全液压湿式驱动桥, 桥壳, 可靠性优化, 响应面法, 近似模型