五轴齿轮组装式离心压缩机转子系统动力学及其非线性特性

发布时间：2018-07-15 20:04

【摘要】：多轴齿轮组装式离心压缩机是能源、石化等领域发展的前沿重大机械装备,转子系统作为多轴齿轮组装式离心压缩机的核心部件,是由多个转子通过齿轮啮合而成,且长期高负荷运转在临界转速以上,转子系统动力特性更为复杂,轴承和齿轮非线性特性对机组工作性能影响非常明显。据统计,我国能源和石油石化行业中运行的大型离心式压缩机组发生的事故以转子故障最多,普遍表现为转子振动过大、转子振动导致的结构损伤时常发生等。长期以来,压缩机制造行业对此类转子系统进行动力学设计时,仍沿用各个转子单独设计的方法,致使某些机器在工作中经常出现严重的异常振动,严重时影响生产甚至造成重大经济损失。因此,开展对多轴齿轮组装式离心压缩机的齿轮耦合多转子-轴承系统进行理论研究,掌握其动力学特性及其非线性特性与振动规律十分必要。本文在国家重点基础研究项目(973项目)“高端压缩机组高效可靠及智能化基础研究”(编号：2012CB026000)课题5“压缩机组复杂系统振动故障机理及智能联锁保护原理与方法”的支持下,以某型号五轴齿轮组装式离心压缩机为对象,开展多轴齿轮组装式离心压缩机的齿轮耦合多转子-轴承系统的动力学特性及其轴承、齿轮和负载等非线性影响规律的理论研究并进行数值模拟和模型试验验证。主要内容如下：采用线性时不变的齿轮啮合模型,提出了基于有限元法的齿轮耦合轴承转子系统动力学线性模型建立方法；根据几何畸变的相似设计方法研制了五轴齿轮组装式离心压缩机转子系统的缩尺模型试验台,通过对比确认了缩尺模型的有效性；获得该试验台转子系统的固有特性及不平衡下的振动响应计算方法,重点研究了不平衡对齿轮耦合转子系统的径向振动、轴向振动和啮合力的影响规律,利用五轴齿式压缩机动力学特性模拟实验台实验结果对计算结果进行了验证。基于流体Reynolds方程,在轴颈的静平衡假设基础上,研究了在不同负载下油膜径向轴承以及油膜推力轴承的动力学参数变化规律,建立了试验台轴承刚度与阻尼系数数据库；基于建立的数据库实现了考虑非线性油膜力的齿轮耦合转子系统动力学特性的快速计算方法,获得了考虑油膜非线性影响下负荷变化对齿轮耦合转子系统动力学特性的影响规律,对多轴齿轮组装式离心压缩机实际运行中的“临界负荷”现象进行了解释,提出了“临界负荷”的确定方法。引入非线性时不变的齿轮啮合模型,建立了考虑齿轮非线性啮合特性的多轴离心压缩机齿轮耦合转子系统整体有限元模型,实现了五轴齿轮组装式压缩机多点啮合多平行轴转子系统动力学与非线性振动的高精度仿真；从齿轮啮合力变化规律入手,系统的研究了齿轮刚度激励、齿轮间隙激励、齿轮传递误差激励以及转子系统负载等因素对转子系统齿轮啮合力的影响规律,进而获得了转子系统的振动规律,并利用试验台测试结果对计算结果进行了验证。本文的研究内容和结论可为多轴齿轮组装式离心压缩机组的动态优化设计、故障监测与诊断提供理论支撑。
[Abstract]:The multi axis gear assembly centrifugal compressor is the leading important mechanical equipment in the energy and petrochemical fields. The rotor system is the core component of the multi axis gear assembly centrifugal compressor. It is formed by the meshing of a number of rotors through the gear, and the rotor system has more complex dynamic characteristics, and the rotor system has more complex dynamic characteristics, and the rotor system is more complex. And the nonlinear characteristic of gear has a very obvious influence on the working performance of the unit. According to statistics, the accidents of the large centrifugal compressor set in the energy and petroleum and petrochemical industry in our country are most caused by the rotor failure, which generally shows that the rotor vibration is too large and the structural damage caused by the vibration of the rotor often occurs. When the dynamic design of this kind of rotor system is carried out, the separate design method of each rotor is still used, so that some machines often have serious abnormal vibration in the work, which seriously affect production and even cause significant economic loss. Therefore, the gear coupling multi rotor bearing system for multi axle gear assembly centrifugal compressor is carried out. It is necessary to carry out theoretical research and grasp its dynamic characteristics, nonlinear characteristics and vibration laws. In this paper, the basic research project of the National Key Basic Research (973 project) "high efficiency reliable and intelligent basic research on high end compressor" (number: 2012CB026000) topic 5 "the vibration fault mechanism of the complex system of compressor group and the intelligent interlocking protection Under the support of the principle and method, the dynamic characteristics of the gear coupling multi rotor bearing system of a multi axle gear assembly centrifugal compressor and the nonlinear influence laws of bearing, gear and load are carried out with a certain type of five axle gear assembled centrifugal compressor as the object. The following contents are as follows: using the linear time invariant gear meshing model, the method of establishing the dynamic linear model of the gear coupling rotor system based on the finite element method is put forward, and the scale model test rig of the five axis gear assembly centrifugal compressor rotor system is developed according to the similarity design method of geometric distortion, and it is confirmed by comparison. The validity of the scale model is obtained. The inherent characteristics of the rotor system and the calculation method of vibration response under the unbalance are obtained. The influence of the imbalance on the radial vibration, the axial vibration and the rodent force of the gear coupling rotor system is studied, and the experimental results of the experimental bench are simulated by the dynamic characteristics of the five axis tooth compressor. The calculation results are verified. Based on the fluid Reynolds equation, based on the static equilibrium hypothesis of the journal, the dynamic parameters of the oil film radial bearing and the oil film thrust bearing are studied under different loads. The database of the bearing stiffness and damping coefficient of the test rig is established, and the nonlinear oil is considered based on the established database. A fast calculation method for dynamic characteristics of a gear coupled rotor system with a membrane force is obtained. The influence of load variation on the dynamic characteristics of a gear coupling rotor system under the influence of oil film nonlinearity is obtained. The "critical load" phenomenon in the actual operation of a multi axle gear assembly centrifugal compressor is explained, and the critical negative effect is proposed. The nonlinear time invariant gear meshing model is introduced. The finite element model of the multi axis centrifugal compressor gear coupling rotor system is established, which takes the nonlinear meshing characteristics of the gear into consideration. The high precision imitation of the dynamic and nonlinear vibration of the multi point meshing multi parallel shaft rotor system of the five axis gear assembly compressor is realized. The law of the influence of gear stiffness, gear clearance, gear transmission error and rotor system load on the gear meshing force of the rotor system is studied systematically, and the vibration law of the rotor system is obtained, and the result of the calculation is carried out by the test result of the test rig. The research contents and conclusions of this paper can provide theoretical support for dynamic optimization design, fault monitoring and diagnosis of multi axis gear assembly centrifugal compressor units.
【学位授予单位】：大连理工大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TH452

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