多工况下微型电动车车身结构拓扑优化设计

Topological optimization design on the body structure of mini electric cars under multi-working conditions

以车身多工况权重刚度最大化为优化目标,以体积比、节点位移及一阶频率为约束条件,建立了微型电动车车身结构多刚度拓扑优化模型。在采用线性加权方法将多刚度这一多目标优化问题转化为单一目标优化的过程中,基于层次分析法提出了多工况权重比的计算方法。该方法使车身优化设计中权重比的设定有据可依,可避免由于设计者主观因素造成的权重比偏差。该多刚度拓扑优化模型体现了车身结构的拓扑优化设计,得到了满足性能要求的清晰车身结构。

Taking the weight stiffness maximization of car body under multi working conditions as the target of optimization, and with the volume ratio, node displacement and the first ordered frequency as the constraint conditions, the multi stiffness topological optimization model of mini electric car body structure was established. In the process of letting the multi stiffness problem of this multi object optimization be transformed as a unitary object optimization by adopting the linear weighting method, the calculation method of multi working states weight ratio was put forward on the basis of layered analysis method. This method made an evidence-based setting of weight ratio in the car body optimization design and could avoid deviations of weight ratio caused by subjective factors on account of the designers. This multi stiffness topological optimization model reflected the topological optimization design of body structure and from this a distinct car body structure that satisfied the performance requirements could be obtained.