考虑螺栓联接结构的轴承-转子系统振动特性分析

针对含螺栓联接结构的轴承-转子系统，建立考虑陀螺力矩及因螺栓预紧力不均匀产生的初始变形量的非线性转子系统动力学模型。采用法求解转子系统运动方程，通过分岔图、时域曲线、频谱及Poincaré映射图研究存在轴承游隙时转子系统的混沌路径，并分析不同初始变形量及轴承游隙对转子系统非线性振动特性的影响，通过试验验证所得结论的准确性。研究表明，当存在轴承游隙时，预紧力不均匀产生的初始变形量增加会抑制低转速下盘的混沌运动，拟周期运动进入混沌运动状态的转速升高，临界转速附近的振动幅值增加，系统混沌路径发生变化；存在初始变形量时，随着轴承径向游隙增大，系统在低转速工作状态下即进入混沌运动运动状态，拟周期运动进入混沌运动状态的转速降低。研究结果可为含螺栓联接结构的轴承-转子系统设计提供理论参考。

Vibration Characteristics of Rotor Bearing System with Bolted Joint Structure

A nonlinear dynamic model of rotor bearing system with bolted joint structure which considering the gyroscopic moment and the initial deformation due to the uneven preload of the bolts is built. The Newmark-β method is utilized to obtain the nonlinear dynamic responses, and the time-domain response, the bifurcation plots, the frequency spectra, the Poincaré maps are used to carry out the routes to chaotic motion of the rotor system with bearing clearance. And then the effects of the initial deformation and the bearing clearance on dynamic responses are analyzed. The results show that with the increasing of the initial deformation, the chaotic motion of the disk at low speed is suppressed when the bearing clearance is present, the rotational speed from the quasi periodic motion into the chaotic state increased, the amplitude of the response near critical speed increased and the routes to chaotic changed; With the increasing of the bearing clearance, the motion state of the system is chaotic under a low rotating speed when the initial deformation is present. And the speed from the quasi periodic motion to chaos motion state is decreased. The results can provide a theoretical foundation for the design of bearing rotor system with bolted joint structure.