基于模态应变能及灵敏度分析白车身模态优化
Modal Optimization of Body-in-White Based on Modal Strain Energy and Sensitivity Analysis

白车身优化过程中，由于板件较多，直接使用模态灵敏度分析的分析对象多且计算量大。本文引入模态应变能分析方法，从而减少模态灵敏度分析对象，提高优化效率。基于模态试验验证的有限元模型，选取模态应变能分析的一阶模态振型下的薄弱位置，缩小模态灵敏度分析的板件范围，再根据灵敏度分析结果对板件厚度进行调整，提高白车身一阶模态频率。最终结果表明，优化后一阶模态频率由15.75 Hz提高到了16.50 Hz，同时白车身质量未增加，实现了白车身模态性能提升的同时车身不增重。
In optimization of body-in-white, a large amount of panels will increase the modal sensitivity analysis objects and computation. So with the modal strain energy analysis, the optimizing efficiency will be increased. Based on the finite element analysis model verified with modal experiment, the large deformation parts of body-in-white and the sensitivities of these parts are defined in modal strain energy analysis and sensitivity analysis. According to the sensitivity analysis results, we improve the first modal frequency with adjusting the thickness of the parts. The final results show that after optimization, the first modal frequency is raised from 15.75 Hz to 16.50 Hz, without weight increase of the body-in-white