基于子模型的车身结构分析与优化

在车身有限元分析中,由于局部结构的尺寸较小,在整车的网格模型下局部无法获得足够精度的计算值,整车车身模型细化网格会显著增加计算时间。解决此问题的方法有子模型技术和子结构技术,其中子模型技术具有明显的优越性。文章将子模型技术应用至某微车强度的计算。获取子模型边界条件,对该子模型进行网格细化处理后再求解。比较计算可得,通过运用子模型技术,在保证仿真精度的基础上提高了计算效率。文章选取实际耐久性试验车的焊点开裂案例,进行基于子模型方法的优化分析,优化时间显著减少,优化后应力值明显减小,解决了开裂问题。

Body Structure Analysis and Optimization Based on Its Sub-model

In the body structural analysis,due to small size of partial structure,we cannot acquire enough precise calculated value in vehicle model.Thinning down mesh size of body model will apparently increase computation time.The techniques to solve such problems are sub-model technique and substructure technique,while the former has significant advantages. This paper applies the sub-model technique to a mini-van for vehicle strength analysis.We can obtain sub-model boundary conditions and recompute its sub—model after fining mesh size.Relatively,the application of the technique apparently improves computational efficiency on the basis of the simulation accuracy.In this paper,a case of weld cracking in a car for durability test was chose for optimization based on the technique,which has notablely decreased optimization time and stress and solved the problem of cracking.