基于多目标的汽车前端框架拓扑优化

针对汽车前端框架的结构和工况特点，建立基于Hyperworks的有限元模型，运用带权重的折衷规划法定义综合目标函数来进行多目标拓扑优化，通过灰色关联法和层次分析法分别计算静态多工况下柔度的权重以及动态低阶频率的权重。结果表明：优化后的汽车前端框架最大变形、最大应力分别降低了21.67%、34.39%；第一阶模态提高了10.56%；质量从3.55kg降低到3.32kg减轻了7%。采用多目标拓扑优化后的汽车前端框架不仅有效提高刚度、强度和固有频率性能基础，还能促进汽车前端轻量化水平的提升。

TOPOLOGY OPTIMIZATION OF AUTOMOBILE FRONT-END FRAME BASED ON MULTI-OBJECTIVE

In view of the characteristics of the structure and working conditions of the front-end frame of the automobile, a finite element model based on Hyperworks was established. The comprehensive objective function for multi-objective topology optimization was defined by the weighted eclectic programming method, and the flexibility weight under static multi-working conditions was determined by the gray correlation method. The results showed that the maximum deformation, maximum stress and first-order mode of the optimized front-end frame of the car were reduced by 21.67%, 34.39% and 10.56% respectively; the mass was reduced from 3.55kg to 3.32kg (7%). The use of multi-objective topology optimization can effectively improve the rigidity, strength and natural frequency performance of the front-end frame of the car, and can also promote the improvement of the lightweight level of the front-end of the car.