Abstract:

The rigid-flexible coupling dynamics modeling and modal analysis were employed to study the system consisted of square plansifter and flexible suspender. Since the body of plansifter and the eccentric object were considered as rigid body and the suspender as elastic body, the circular equation of steady-state vibration of the plansifter body and the cantilever beam model of suspender were established respectively. The natural frequency of the system and the equivalent bending stiffness of the suspender were deduced. By using FEA, the first 20 modes and the displacement response were obtained from the normal mode analysis and the transient response analysis respectively. It is shown that the dynamics relationship between the body of plansifter and the suspender can be well revealed by the theoretical model, and the real vibration characteristics can be simulated accurately by
FEA whose loads and boundary conditions are based on the theoretical analysis. 

Key words: rigid-flexible coupling, square plansifter, dynamics modeling, cantilever beam, mode, FEA

摘要：

针对高方平筛和其上固结的柔性吊杆组成的动力学系统，进行了刚柔耦合的动力学建模和振动模态分析。将筛体—偏重块系统和吊杆分别作为刚体和弹性的可变形体，建立了筛体稳态圆振动方程和吊杆悬臂梁力学模型，总结出系统固有频率的计算方法。在此基础上，采用有限元方法对系统进行了模态计算和动力学响应分析。结果表明，理论模型能够很好地反映筛体与吊杆之间的动力学耦合关系；以理论分析为基础的载荷和边界条件的设置，使有限元仿真结果较准确地模拟了系统实际的振动特性。

关键词: 刚柔耦合, 高方平筛, 动力学建模, 悬臂梁, 模态, FEA