基于光滑策略的复合材料车身结构动力特性分析

Dynamic Characteristics Analysis of Automotive Components with Composite Material Based on Smoothing Strategy

复合材料在汽车车身轻量化结构设计中的应用受到了越来越多的关注,为了进一步改善和提高车身复合材料零部件结构动力特性分析中的数值精度等工程问题,本研究采用光滑策略重新构造层合三角形壳元并将其应用于车身复合材料零部件的动力特性分析中.该构造策略通过离散剪切间隙来消除剪切自锁,采用梯度光滑策略来合理调整车身复合材料结构的系统刚度矩阵,有效避免了过硬现象.通过光滑策略所构造的层合壳元分析了车身复合材料构件的动力特性,并与有限元商业软件计算结果进行了精度对比.研究结果表明,无论复合材料各层之间是正交或斜交情况,本研究所实施的光滑策略都能使车身复合材料零部件的模态计算结果精度得到一定的提高.

More and more attention have been paid to composite materials used in automotive body lightweight design.In order to further improve and enhance the numerical accuracy for dynamic analysis of automotive structure made from composite materials,this paper presents a smoothing strategy to conduct laminated shell element which is used in dynamic characteristics analysis of composite structural components.By the proposed smoothing strategy,the shear locking is successfully alleviated by means of the discrete shear gap method,and the system stiffness matrix is effectively tuned after employing the gradient smoothing technique aiming to avoid the“over-stiff”phenomenon.Both typical automotive components including engine cover and door made from composite materials are performed in dynamic characteristics analysis,and the accuracy of the obtained results is compared with existing finite element commercial software.The results from both typical engineering examples show that the proposed smoothing strategy makes the computational results higher accuracy,regardless of whether the layers of the composite are orthogonal or oblique.