面向全矢谱分析的转子动态故障特性研究

发布时间：2018-05-22 08:32

本文选题：全矢谱 + 转子动力学　；参考：《郑州大学》2012年硕士论文

【摘要】：转子系统结构参数(如刚度、阻尼等)、偏心质量(外激励)等对系统的动力学特性有很大的影响,而基于振动检测的故障诊断过程实质上是根据转子系统动力学响应的特征来分析其刚度,阻尼以及激励可能产生的变化。全矢谱技术是一项采用信息融合的思想来客观描述转子-轴承系统动力学响应中一些关键特征量的实用技术,全矢谱中的各特征参数可作为转子系统故障诊断的依据。因此,根据转子动力学和全矢谱理论来分析并建立转子系统动力学参数(如支承刚度等)与全矢谱参数(如主振矢、振矢角等)的关系有十分重要的意义。大部分旋转机械的支撑具有各向异性,即支撑的各方向具有不同的刚度或阻尼。为了分析水平/竖直方向上的刚度、阻尼以及偏心质量的分布与全矢谱各参数的之间的关系,本文建立了相应的转子-轴承系统的有限元模型,利用有限元分析方法进行数值模拟,然后通过转子试验台进行实验验证。通过水平和竖直方向上的刚度变化与全矢谱参数的关系的研究结果表明：在恒定转速下,改变两相互垂直方向上的刚度,则主振矢、副振矢和方位角均随刚度的变化而变化,通过实验对这一结论进行了验证。根据上述结论,提出依据偏心率进行故障判别的方法,根据轴承刚度对振矢和方位角的影响给出传感器的安装原则,从而提高对转子系统故障监测的准确性。通过有限元分析方法对轴承阻尼与全矢谱参数之间的关系进行分析,数值模拟结果表明：阻尼对主振矢、副振矢以及振矢角均有影响。阻尼可以降低转子系统的振动量,使振矢值减小,轴心轨迹的偏心率也有一定程度上的降低,故轴承阻尼对振动有一定的抑制作用。就转子-轴承系统的偏心质量对全矢谱参数影响的分析结果表明：在忽略交叉刚度和阻尼的情况下,圆盘的偏心质量只对主振矢和副振矢有影响,而对运动轨迹的偏心率和振矢角没有影响,即偏心质量只对轴心运动轨迹的大小有影响,对轴心轨迹的形状和位置没有影响。本文所确立的转子系统参数和全矢谱参数之间关系的结论,可以较好地应用于旋转机械的故障机理研究中,从而提高故障诊断的准确率
[Abstract]:The structural parameters of rotor system (such as stiffness, damping, etc.) and eccentric mass (external excitation) have great influence on the dynamic characteristics of the system. The process of fault diagnosis based on vibration detection is based on the characteristics of dynamic response of rotor system to analyze the possible changes of stiffness, damping and excitation. The whole vector spectrum technique is a practical technique to objectively describe some key characteristic variables in the dynamic response of rotor-bearing system using the idea of information fusion. The characteristic parameters in the full vector spectrum can be used as the basis for fault diagnosis of the rotor system. Therefore, it is of great significance to analyze and establish the relationship between the dynamic parameters of rotor system (such as support stiffness) and the full vector spectrum parameters (such as main vibration vector, vibration vector angle, etc.) according to rotor dynamics and total vector spectrum theory. The support of most rotating machinery is anisotropic, that is, the stiffness or damping of the bracing is different in each direction. In order to analyze the relationship between stiffness, damping and eccentric mass distribution in horizontal / vertical direction and the parameters of full vector spectrum, a finite element model of rotor-bearing system is established in this paper. The finite element analysis method is used to simulate the rotor test rig. The relationship between the stiffness variation in horizontal and vertical directions and the total vector spectral parameters is studied. The results show that the main vibration vector, the secondary vibration vector and the azimuth change with the change of stiffness when the stiffness of the two vertical directions is changed at constant rotational speed. This conclusion is verified by experiments. According to the above conclusions, the method of fault diagnosis based on eccentricity is put forward, and the installation principle of sensor is given according to the influence of bearing stiffness on vibration vector and azimuth angle, so as to improve the accuracy of fault monitoring of rotor system. The relationship between the damping of bearing and the parameters of full vector spectrum is analyzed by finite element method. The numerical simulation results show that the damping has an effect on the main vibration vector, the secondary vibration vector and the angle of the vibration vector. Damping can reduce the vibration of the rotor system, reduce the vibration vector, and reduce the eccentricity of the axis trajectory to a certain extent, so the bearing damping has a certain inhibitory effect on the vibration. The results of the analysis of the effect of the eccentric mass of the rotor bearing system on the parameters of the full vector spectrum show that the eccentric mass of the disk only affects the main vibration vector and the secondary vibration vector when the cross stiffness and damping are ignored. But it has no effect on the eccentricity and the angle of vibration vector, that is, the eccentric mass has no effect on the shape and position of the axis track, but only on the size of the axis track. The conclusion of the relationship between the rotor system parameters and the total vector spectrum parameters established in this paper can be well applied to the study of the fault mechanism of rotating machinery, thus improving the accuracy of fault diagnosis.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH165.3

【引证文献】