陈小华

摘 要：本文旨在通過某中卡驾驶室前悬置的结构优化设计过程，阐述如何在给定空间，根据车辆结构的使用要求寻找出其材料的最佳布局方式，从而使车辆结构最大限度地实现轻量化。 传统结构优化设计过程大致为假设-分析-校核-重新设计，有时这个过程需要重复多次，很难找出最佳设计方案，用材裕度一般较大。本文前悬置的结构优化设计中，直接优化出其结构材料的最佳布局从而实现前悬置的轻量化。其优化设计方法过程如下：确定前悬置相关的极限强度工况（七种）和安全法规要求的前拍工况，运用多体软件建立中卡整车模型，分析提取极限强度工况载荷；建立驾驶室前拍工况模型，计算提取前拍工况载荷；建立前悬置的优化模型，施加前面提取的工况载荷，以优化设计区域密度作为优化设计变量，把各工况下的计算应力和体积作为响应，把材料屈服强度作为约束边界，以体积最小作为优化目标进行优化分析，从而得出前悬置结构材料的最佳布局方式。根据优化结果，设计人员设计出的样件一次性通过了实际强度试验验证和碰撞安全前拍工况的摸底试验，这一优化方法大大地缩短了前悬置结构的开发周期和试验时间，也节省了开发试验费用。也说明CAE技术在产品概念开发和产品设计阶段具有重要的指导参考作用。

关键词：前悬置 轻量化 多工况 拓扑优化

Topology Optimization Design of Front Mounting of a Medium Truck Cab

Chen Xiaohua

Abstract：This paper aims to explain how to find the best layout of the material according to the use requirements of the vehicle structure in a given space through the structural optimization design process of the front suspension of a medium-truck cab， so as to maximize the lightweight of the vehicle structure. The traditional structural optimization design process is roughly divided into  hypothesis， analysis， check， redesign. Sometimes this process needs to be repeated many times， and it is difficult to find the best design scheme， and the material margin is generally large. In the structural optimization design of the front suspension in this paper， the optimal layout of its structural materials is directly optimized to achieve the lightweight of the front suspension. The optimization design method process is as follows： to determine the ultimate strength working conditions related to the front suspension （seven types） and the front shooting conditions required by safety regulations， use multi-body software to establish the vehicle model of medium truck， and analyze and extract the load of the ultimate strength condition， and the model of the pre-cab shooting condition， and calculate the load of the extraction pre-shooting condition. The optimization model of the front suspension is established， the load of the working conditions extracted in front is applied， the density of the optimization design area is used as the optimization design variable， the calculated stress and volume under each working condition are taken as the response， the yield strength of the material is used as the constraint boundary， and the minimum volume is used as the optimization goal for optimization analysis， so as to obtain the optimal layout method of the pre-suspension structural material. According to the optimization results， the sample designed by the designer passed the actual strength test verification and the bottom test of the collision safety pre-shooting condition at one time， which greatly shortened the development cycle and test time of the front suspension structure， and also saved the development test cost. It also shows that CAE technology has an important guiding reference role in product concept development and product design stage.

Key words：front overhang， lightweight， multi-condition， topology optimization

1 绪论

汽车轻量化不仅会减少结构用材，而且会使整车动力性提高，制动安全距离缩短，燃油消耗率降低，同时降低尾气排放量，据统计车辆每减重10%，每百公里可节省燃油6%-8%，尾气排放量也相应减少7%左右[1]。……