多平行轴齿轮耦合转子系统的振动响应

以一个两对斜齿轮耦合的三平行轴转子系统膨胀机子系统为研究对象,建立了斜齿轮啮合副动力学模型和转子系统有限元模型,考虑了齿轮啮合刚度、方位角、啮合角、螺旋角以及主动轴转动方向的影响,推导出齿轮啮合刚度矩阵。基于模态叠加法,对弯-扭耦合转子系统膨胀机子系统进行了固有特性分析和瞬态方式的不平衡响应分析,得到齿轮啮合前、后系统加载处的不平衡响应变化曲线。研究表明,齿轮间的耦合使系统之间的振动强烈,系统可能会在某个非固有频率处不平衡响应进行积累叠加,出现最大振动的现象,同时识别出共振峰的产生机理。齿轮耦合对转子系统动力学特性产生了很大的影响,使系统振型表现为耦合振型,必须以耦合的方式分析系统的振动特性,为防止系统发生大的振动提供依据,对齿轮系统的设计和故障分析具有指导意义。

Vibration Response of Multi-shaft Rotor System with Coupled Gear Mesh

With a two pairs of helical gear coupled rotor system expander subsystem with three parallel axes being studied, helical gear meshing pair dynamics model and finite element model of rotor system are established, in which the effect of mesh stiffness, gear position angle, transverse pressure angle and helical angle are taken into consideration. Also the gear meshing stiffness matrix is derived. The analysis of natural characteristics and unbalance response of the coupled lateral-torsional expander subsystem are then analyzed based on MSM (mode superposition method). Unbalanced response curves of system loading point are compared with considering meshing or not. The result shows that the vibration between the systems becomes intense due to the coupled gears. Unbalance response of the system maybe accumulated until the existence of the maximum vibration phenomenon in a non-natural frequency. Meanwhile, the generation mechanism of resonance peaks is identified. The system vibration mode is performed as the coupled mode because the coupled gear exerts a profound influence on the dynamic characteristics of the rotor system. So the vibration characteristics of the system must be analyzed with the coupled method, which can provide the basis for preventing the big vibration of the system, and also give the guiding significance to the design and fault analysis of the gear system.