基于灵敏度及尺寸优化的汽车车门轻量化

Research on the Lightweight of Vehicle Door Based on Sensitivity and Size Optimization

以国产某小车车门为研究对象,建立车门有限元模型,对车门进行垂直、侧向刚度分析,并进行自由模态分析和模态试验,验证模型的有效性。计算各部件对车门刚度和一阶模态的灵敏度,确定敏感区域。基于灵敏度分析方法,以车门质量最小为目标函数,在保证车门刚度和一阶模态频率不降低的前提下,结合尺寸优化设计方法优化车门各部件厚度。优化结果表明,车门下沉刚度提高了12.03%,水平刚度提高了1.04%,一阶模态频率提高了0.2 Hz,车门的总质量下降了4.74%,达到了良好的轻量化效果。

Taking a vehicle door of a certain home-made car as research subject, its finite element model is established. Analyzing its vertical stiffness, lateral stiffness and modal, the modal value is compared with test to ensure the model effectiveness. Calculate each part sensitivity of stiffness and modal to determine the sensitive region. Based on sensitivity analysis, the minimum door mass is defined as the objective function. Under the preequisite of emsuring a of good stiffness and modal, sensitivity analysis method with size optimization is combined to optimize each components thickness. The optimization show that, the vertical stiffness is increased by 12.03%, lateral stiffness is increased by 1.04% and the first order modal is enhanced about 0.2Hz. At the same time the total mass is reduced about 4.74%. Therefore, the lightweight design in this paper is effective.