商用车复合材料传动轴力学特性

通过计算确定了复合材料传动轴载荷,采用Abaqus建立了传动轴有限元模型。基于有限元法对复合材料传动轴、复合材料与金属混合传动轴、金属传动轴分别进行了静力分析、模态分析、屈曲分析,并对计算结果进行了校核。在此基础上,建立复合材料传动轴与混合轴的Isight模型,基于正交设计方法进行方案优化。优化后的方案提高了2种传动轴的扭转强度、扭转刚度、一阶弯曲固有频率和复合材料传动轴的屈曲扭矩值。利用Abaqus内聚力单元模拟胶层,通过分析胶接的参数,设计了复合材料的胶接接头。

New tangent stiffness matrix for geometrically nonlinear analysis of space frames

A three-dimensional beam element is derived based on the principle of stationary total potential energy for geometrically nonlinear analysis of space frames. A new tangent stiffness matrix, which allows for high order effects of element deformations, replaces the conventional incremental secant stiffness matrix. Two deformation stiffness matrices due to the variation of axial force and bending moments are included in the tangent stiffness. They are functions of element deformations and incorporate the coupling among axial, lateral and torsional deformations. A correction matrix is added to the tangent stiffness matrix to make displacement derivatives equivalent to the commutative rotational degrees of freedom. Numerical examples show that the proposed dement is accurate and efficient in predicting the nonlinear behavior, such as axial-torsional and flexural-torsional buckling, of space frames even when fewer elements are used to model a member.