基于振型转换的螺栓连接梁非线性振动研究  

Non-linear dynamic response of a beam with bolted joint based on modal shape transfer

作　　者：卫洪涛[1] 孔宪仁[2] 王本利[2] 张相盟[2] 

机构地区：[1]郑州大学力学与工程科学学院,郑州450001 [2]哈尔滨工业大学卫星技术研究所,哈尔滨150086

出　　处：《振动与冲击》2014年第12期42-47,92,共7页Journal of Vibration and Shock

基　　金："微小型航天器系统技术"长江学者创新团队发展计划(IRT0520)

摘　　要：以一端固支一端带螺栓连接的梁为对象,采用Iwan模型对螺栓连接的非线性力学特性——迟滞非线性进行建模,基于振型转换的思想,利用相对振型转换法处理了迟滞边界条件引起的非线性振型之间的转换,研究了螺栓连接非线性对梁受迫振动响应的影响。通过梁端点的幅频响应图,讨论了振型之间的耦合、Jenkin's单元的个数、激励力幅值、模态阻尼及螺栓连接刚度对梁端点响应的影响。结果表明,新方法在处理带迟滞非线性边界的连续体振动问题时,具有良好的收敛性;迟滞非线性对系统响应影响有限,在指定的扫频区间仅表现出单周期运动,以及弱频率漂移现象;带迟滞非线性边界条件梁的各参数中,频率漂移的程度对螺栓刚度的大小较敏感。The forced vibration of a beam with one end clamped and the other end bolted was studied.The nonlinear force-displacement characteristics of a bolted joint modeled using Iwan model were used to study the effect of nonlinearities in the bolted joint on the dynamic response of the beam based on the modal shape transfer principle.The modal shape transfer between different modal shapes caused by the hysteretic boundary condition was treated adopting the relative modal shape transfer method.The effects of the coupling between modes,the number of Jenkin＇s elements in Iwan model,the amplitude of the external excitation force,the modal damping and the stiffness of the bolted joint on the response of the beam＇s end were discussed with the frequency-amplitude response of the beam＇s end.It was shown that the new approach has a good convergence when dealing with the vibration problem of a continuous system with hysteretic boundary condition,the effect of the nonlinearity on the dynamic response of the beam system is finite,one-period motion and weak frequency-shift are revealed in a specified frequency-sweeping range,and the level of frequency-shift is sensitive to the stiffness of the bolted joint.

关 键 词：模态分析 梁 非线性振动 迟滞边界条件 振型转换 

分 类 号：V414[航空宇航科学与技术—航空宇航推进理论与工程]