齿轮组装式压缩机转子系统多点啮合时变特性及其耦合振动研究

This project is taking the integrally geared compressor as research object, and focusing on solving the problems of excessive vibration and complex nonlinear behaviors of its geared rotor system with multipoint mesh. Considering the multipoint meshing properties of the central driving gear, the time-varying features of nonlinear meshing force and its influence on the vibration of geared rotor system are investigated after the analysis of gear meshing error, backlash, mesh misalignment, etc. Based on the assumption of Newtonian fluid, a characterization method for nonlinear support forces of rotor system is investigated, and the dynamic model of geared rotor system in the integrally geared compressor is proposed. Meanwhile, the variation characteristics of nonlinear oil film force as well as the dynamic characteristics of the geared rotor system under the large load variation conditions during the working process are studied. Then, the complex combined mode, mode transfer characteristic, together with the sub harmonic resonance, super harmonic resonance, combination resonance and other coupled vibration behaviors of the geared rotor system are studied, while the energy transfer and energy distribution in the geared rotor system are discussed under different running states, in order to realize the prediction of its vibration response with unbalance and misalignment excitation. The results of this study could provide theoretical support for dynamic design and fault diagnosis of geared rotor system with multipoint mesh aiming at high reliability and low vibration.

以齿轮组装式压缩机为研究对象，针对其多点啮合齿轮转子系统振动大、非线性环节复杂等问题，考虑中央驱动齿轮多点啮合特点，研究齿轮啮合误差、齿侧间隙、偏载等因素影响下的齿轮非线性啮合力时变特性及其对转子系统振动的影响规律；基于牛顿流体假设，研究转子系统非线性支撑力的表征方法，建立组装式压缩机多点啮合齿轮转子系统的动力学模型，获得多点啮合齿轮转子系统在设备运行过程中负荷大幅变化下非线性油膜支撑力的变化特征以及转子系统动力学特性变化规律；揭示系统的复杂组合模态与模态转移特性、亚谐与超谐及其组合共振等耦合振动规律，获得不同运行状态下的能量传递与分布规律，实现不平衡、不对中激励下多点啮合齿轮转子系统的振动响应预估，为实现高可靠性、低振动的多点啮合齿轮转子系统动力学设计和故障诊断提供理论支撑。

多点啮合齿轮转子系统是齿轮组装式压缩机的关键基础部件，也是故障的高发部件，其复杂动力学特性以及实际运行中不可避免的振动故障问题，直接决定着整个系统设备的工作性能和安全性。多点啮合齿轮轴承系统的振动耦合现象十分明显，尽管在齿轮、轴承故障诊断方面已有大量学术论文发表，但这些技术和分析方法大都针对齿轮、轴承的单独个体，缺乏对齿轮转子系统整体的综合分析。本项目针对以上问题开展了齿轮组装式压缩机转子系统多点啮合时变特性及其耦合振动研究，主要完成了以下内容：.基于ANSYS研究了齿轮关键接触区域的应力分布规律，提出了一种采用ANSYS数值有限元法求解的运动载荷准静态模型，并对载荷变化进行了修正，获得了由于齿轮轴平行不对中引起的齿轮偏载作用下的齿轮轮齿应力分布规律；.基于二维Reynolds方程，对某齿轮-油膜轴承系统采用的圆瓦轴承油膜的非线性力学特性进行了研究，在轴颈的静平衡假设基础上，重点研究了在不同负载下油膜径向轴承的刚度特性和阻尼特性参数变化规律；.开展了齿轮耦合作用对齿轮传动系统不平衡、不对中响应特性影响规律的研究。在此基础上，获得了不平衡大小以及相位对齿轮耦合转子系统径向振动的影响规律，以及不平衡、不对中、负载等对转子系统振动以及齿轮啮合力的影响规律；.考虑到组装式压缩机转子系统非线性环节较多，计算较为困难，忽略齿轮非线性激励，开展油膜轴承非线性特性的影响因素的研究，进而分析了温度、负载等因素对转子系统振动特性的影响规律研究；.在已有研究的基础上，对齿轮-转子-箱体振动传递特性进行了理论分析。忽略了转子支承与箱体之间的动力耦合项，获得了考虑齿轮自激振动影响下的齿轮箱不平衡振动响应特征，以及各轴承支承力的变化特征，分析了轴承与齿轮箱相互作用的特点与规律。