基于一种新型三角形壳元的汽车车身部件模态分析  

Modal Analysis of Vehicle Body Based on a Novel Triangular Shell Element

作　　者：崔向阳[1] 李光耀[1] 徐峰祥[1] 

机构地区：[1]湖南大学汽车车身先进设计制造国家重点实验室,长沙410082

出　　处：《机械工程学报》2011年第6期101-106,共6页Journal of Mechanical Engineering

基　　金：国家自然科学基金(11002053);国家重点基础研究发展计划(973计划;2010CB328005);中央高校基本科研业务费;汽车车身先进设计制造国家重点实验室资助课题(60870005)资助项目

摘　　要：针对现有的三角形壳元难以用于汽车车身模态分析的问题,提出一种基于边光滑的三角形壳元用于汽车车身部件的模态分析。壳单元公式基于一阶剪切变形理论,并采用离散剪切间隙有效地消除剪切自锁。问题模型首先离散成可自动生成的非结构三角形网格,并在三角形网格的基础上进一步形成基于边的积分区域。提出一种基于边的局部坐标系统,并在局部坐标系内通过梯度光滑技术获得积分域内的光滑应变,从而调节系统刚度,有效地改善结果的精度。基于光滑迦辽金格式构造离散系统方程,并建立基于边光滑三角形壳元的刚度矩阵和质量矩阵列式,对复杂的汽车车身部件进行模态分析。通过与现有软件和参考结果的对比,验证所提算法的有效性和高精度。As the existing triangular shell elements are difficult for simulation of vehicle body,a novel triangular shell element using edge-based smoothing operation is proposed for modal analysis of vehicle body parts.The formulation is based on the first order shear deformation theory,and a discrete shear gap method is employed to mitigate the shear locking.The domain is first discretized into a set of unstructured triangular meshes,and the integration domains associated with the edges of the triangles are then further formed.An edge local coordinate system is introduced for performing strain smoothing operations in each integration domain,and the system stiffness matrix is tuned effectively,which can obtain very accurate results.The discretized system equations are obtained by using the smoothed Galerkin weak form,and the stiffness and mass matrices are formulated.Modal analyses of complex vehicle body parts are studied and comparisons are made with the existing software and reference results,and which verify the effectiveness and high precision of the proposed algorithm.

关 键 词：三角形壳元 模态分析 梯度光滑技术 

分 类 号：TH-55[机械工程]