车身有限元建模与验证研究

The research on body finite element modeling and validation

随着计算机技术和数值分析的不断发展,CAD与CAE技术已在当今汽车设计过程中普遍采用。首先采用CATIA建立某轻型客车的简化车身几何模型,在此基础上采用HyperMesh进行网格划分。考虑到车身曲面形状复杂程度和计算精确度的要求,主要采用了四边形单元来划分网格,在一些对模型精度影响不大或曲面较复杂的地方采用三角形单元来划分网格,将得到的网格化模型导入AN-SYS,计算得到各阶固有频率及模态振型。最后通过试验,将试验模态与计算模态进行对比分析,验证所建车身有限元模型的可靠性,从而为后续车身动力学特性分析打下基础。

With continuously development of numerical analysis and computer technology,CAD and CAE technology have been adopted commonly in the process of today＇s automotive design.A simplified geometric model for minpassenger car body with CATIA is established first,on which HyperMesh has applied to mesh legitimately.Taking into account the complexity of the body curved surface and requirements of computational accuracy,quadrilateral element ha been mainly adopted to mesh the grid,In some areas with less requirement of accuracy and more complex surfaces,triangular element is acceptable to mesh the grid,and the meshing model has been imported to ANSYS to calculate natural frequency and modal shape for each order.Finally,by comparing the test mode with the computational modal,the reliability of the finite element model of the body is verificated that lay a foundation for analysis of dynamic characteristics of the body.