【作者】 陆永杰；

【导师】 郑惠萍；

【作者基本信息】 河北科技大学 ， 机械电子工程， 2010， 硕士

【摘要】 大型旋转机械是国家基础设施和基础工业中最关键和最核心的设备,其安全稳定地运行对国民经济健康发展起着至关重要的作用。转子-轴承系统是旋转机械中最核心的部分,轴系的稳定性关系到机器是否能安全可靠地运行。对轴系的稳定性进行分析不仅是重大的基础科学研究课题,而且有助于解决大型旋转机械在运转过程中的动力学问题,因此转子-轴承系统的运动稳定性问题日益受到关注。本文对《非线性转子系统稳定性量化分析方法》一文中给出的转子系统3种典型运动稳定裕度的定义及其规律进行了实验研究,验证了其在实际转子系统中应用的可行性。首先对转子-轴承系统动力学研究现状及其发展趋势做了综述。其次重点介绍了利用轨线保稳降维方法提出的转子系统稳定性的量化分析方法:即在一维观察空间的外力位移扩展相平面上定义动态中心点,研究转子系统中常见的几种运动形式的动态中心点动能差序列的特点,给出这几种典型运动形式的轨线稳定裕度的定量评估指标及其计算方法,应用灵敏度分析技术快速有效地预测周期运动的倍周期分岔点和Hopf分岔点。采用Capone非线性油膜力模型,对一个Jeffcott转子系统模型的稳定性进行了数值仿真分析;然后基于轨迹特征分析的转子系统3种典型运动稳定裕度的定义,利用灵敏度分析方法,通过两个算例对该系统在两种不同质量偏心时的周期运动分岔点进行了预测。最后基于稳定性的量化分析方法中所给出的转子系统3种典型运动稳定裕度的定义,分别在单跨和双跨转子系统中通过实验研究了其规律,并验证了其可操作性。结果表明:工频周期运动稳定裕度的定义在实际应用中有一定的难度,其可操作性差,建议从稳态数据挖掘并重新给出工频周期运动稳定裕度的定义;倍周期运动和概周期运动稳定裕度定义在实际应用中可操作性较好,但是概周期运动稳定裕度的定义在取数计算时不好把握。更多还原

【Abstract】 Large-scale rotary machines are key equipments in national basic industry. The safety in productions is of very significance to social life and economic development. Rotor-bearings system is the kernel mechanism rotary machinery, which stability is key to safe operation. It is not only a great basic scientific research subject to study the stability of rotor bearing system, but also helpful to solve the dynamic problems when large-scale rotating machinery is in the process of operation. So the stability of rotor bearing system motion has been paid attention increasingly. In this paper, a feasibility experimental research was studied in actually rotor system with the definitions and regularity of the three kinds of typical motion stability margins, which come from the paper‘Quantitative Methodology for the Stability Analysis of Nonlinear Rotor Systems’.Firstly, the research status and development tendency of rotor-bearing system dynamics are summarized. And then especially put the stress on the quantitative methodology for the stability analysis of rotor systems, which is presented based on trajectory. Dynamic center point (DCP) of a subsystem is defined on the extended phase plane, namely force-position plane. Characteristics of curves on the extended phase plane and the kinetic energy difference sequence of the DCP for general motion in rotor system are studied. The corresponding stability margins of trajectory are evaluated quantitatively.A numerical simulation analysis for the Jeffcott rotor system stability is carried out by means of the Capone nonlinear oil force model. Then a bifurcation point prediction to the system response is done through two examples at two different mass eccentricities by sensitivity analysis, which is based on the three kinds of typical motion stability margin definition of the rotors system.Finally, the change rule was studied by means of experiment in a single and double span rotor system respectively which based on the definition of the three kinds of typical motion stability margin of rotor bearing system with lubricated bearings and its operability was verified. The result shows that the definition of frequency periodic motion stability margin has a certain difficulty in the practical applications and has poor maneuverability. It is proposed to re-give the definition of frequency periodic motion stability margin and mine it from steady-state data. The definition of double periodic motion and quisa periodic motion stability margin are better in the practical application operability, but the latter has a certain difficulty in selecting and calculating data.更多还原