等参单元在货车转向架强度计算中的应用

推导了八节点六面体等参单元的应变矩阵、刚度矩阵,对该单元的位移解收敛性和畸变敏感性进行了分析。针对转向架强度分析的特点,在MATLAB平台上开发了一套求解位移的有限元程序。该程序通过读取ANSYS软件输出的数据文件中的模型信息,采用八节点六面体等参单元,求出单元刚度矩阵及单元体积力矩阵,组集单元,引入位移边界条件,得到一组以节点位移为未知量的多元线性方程组,求解得到单元节点位移。最后对160 km/h货车转向架侧架的主要载荷进行了位移计算,结果与ANSYS软件计算结果基本吻合。

Application of Isoparametric Element in Strength Calculation for Freight Car Bogie

In this paper, strain and stiffness matrix of isoparametric element with eight nodes and hexahedron are derived in detail. Element performance analysis of displacement convergence and distortion sensitivity is carried out. Based on MATLAB platform, a series of finite element procedures are developed to get displacements in accordance with the structure strength characteristic of bogie. Modal information can be got from the reading of the database file outputted by ANSYS software. Element stiffness matrix and volumetric force matrix are obtained. Then, elements are fabricated. Furthermore, displacement and border factors are considered and a group of linear simultaneous equations are generated with displacements as unknowns, through which node displacements are obtained. Finally, bogie side bearer displacements of 160 km/h wagon with the main force are calculated. The results are almost the same as those obtained from the software ANSYS.