大变形曲梁多体系统动力学建模

为了提高大变形曲梁多体系统数值仿真的计算精度和计算效率,引入弧线坐标,采用曲梁单元,从非线性应变关系式出发,用绝对节点坐标法建立了大变形曲梁多体系统的动力学模型,该方法的特点是不需要引入单元转换矩阵,收敛性好。用曲梁单元模型对曲梁单摆进行数值仿真计算,将计算结果与将曲梁细化为若干个直梁单元的动力学模型的计算结果进行对比,验证了曲梁单元动力学模型的准确性和有效性。在此基础上用曲梁单元模型实现了四连杆曲梁多体系统的动力学仿真。

Dynamic Modeling for Curved Multibody Beam System with Large Deformation

In this paper,curved beam element model was proposed in order to improve the computational accuracy and efficiency of a curved beam multibody system with large deformation.By using arc coordinate and curved beam elements,dynamic model of curved beam multibody system was established based on absolute coordinate formulation,which takes into account geometric nonlinear effect.The advantage of the model is that the transformation matrices are not needed.Furthermore,the convergence of the curved beam element model is better than that of the conventional straight beam model.Simulation of a single curved beam pendulum was carried out to show the accuracy and efficiency of the curved beam element model by comparison with the simulation results obtained from the straight beam element model.Finally,the curved beam element model was used to simulate a four-bar mechanism with large deformation.