摘要
间隙和约束的存在,使动力机械系统表现出丰富的非线性动力学行为.考虑具有对称刚性约束碰撞振动系统,应用数值计算的方法,研究系统在简谐激励力作用下的动力学响应和阻尼系数对振动特性的影响.通过定义描述系统周期特性和冲击振动特性的两种Poincaré截面,分析了系统基本周期振动和亚谐振动的模式多样性及冲击振动的转迁规律.结果表明,系统在低频带主要呈现基本周期碰撞振动,其随频率递减连续发生Grazing分岔,对称约束位置的碰撞次数随Grazing分岔的产生逐次分别加一,当碰撞次数足够大时,系统呈现非完全颤碰振动.随频率进一步递减,碰撞次数无限增大,非完全颤碰振动发生Sliding分岔,转迁为含粘滞特性的完全颤碰振动.
The existence of clearances and constraints makes the power machinery system exhibit rich nonlinear dynamic behaviors.Considering the vibration system with symmetric rigid constraints,the dynamic response under disturbance of harmonic force and the influences of damping coefficient on the vibration characteristics were studied by using the method of numerical calculation.Based on two kinds of Poincarémapping which describe system periodical characteristics and impact vibration characteristics,pattern types and the transition law of fundamental and subharmonic motions were analyzed.The results show that the system mainly presents periodic-impact motion in low exciting frequency range.As the exciting frequency is small,the incomplete chattering-impact motion appears with a succession of grazing bifurcation,the number of impacts occurring at the constraints of the clearance increases one by one.As the exciting frequency further decreases,the number of impacts increases indefinitely.Finally,the complete chattering-impact motion with sticking will occur with decreasing the exciting frequency up to the sliding bifurcation boundary.
作者
杨艳
侍玉青
YANG Yan;SHI Yu-qing(School of Mechatronic Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《兰州交通大学学报》
CAS
2020年第4期83-89,共7页
Journal of Lanzhou Jiaotong University
基金
甘肃省科技计划项目(1508RJYA004)。
关键词
间隙
振动
粘滞
颤碰
分岔
clearance
vibration
sticking
chattering-impact
bifurcation
