往复滑动摩擦副磨合过程切向和法向摩擦振动相关性研究

发布时间：2018-02-27 01:35

本文关键词： 摩擦副磨合摩擦振动互相关理论相关分析　出处：《大连海事大学》2017年硕士论文　论文类型：学位论文

【摘要】：摩擦振动是摩擦副磨合磨损过程中表面微凸体碰撞产生的一种物理现象,是摩擦学系统的输出特征之一,蕴涵着反映摩擦副磨合磨损过程的摩擦学信息和动力学信息。然而,摩擦振动是低信噪比的微弱信号,常被强烈的背景噪声所淹没,难以反映摩擦副磨损状态的变化,因此如何实现摩擦振动信号的提取和识别显得尤为重要。相关分析研究的是信号间的相互依存关系,可用于信号的识别和提取。摩擦磨损过程中表面微凸体碰撞能同时激发切向和法向摩擦振动,二者为同源信号,存在一定的依存关系。因此,通过切向和法向摩擦振动的相关性研究可为摩擦振动识别和提取提供一种新思路。本文以往复滑动摩擦副磨合磨损试验中采集的摩擦振动信号为研究对象,应用互相关理论对摩擦振动信号的相关性进行了研究,主要的研究内容和结论如下:首先,应用互相关理论对试验过程中采集的含有噪声的摩擦振动信号进行了分析,结果表明,含有噪声的切向和法向摩擦振动信号存在时间延迟,互相关系数小,相关程度低。因此,含有噪声的信号不能反映切向和法向摩擦振动的同源特性。为了剔除噪声的影响,应用谐波小波包变换理论对采集的摩擦振动信号进行降噪,提取了反映摩擦副磨合磨损状态变化的信号,并对其进行了相关分析,结果表明:降噪后的切向和法向摩擦振动信号无时间延迟,互相关系数大,相关程度高。因此,经谐波小波包降噪后的信号反映了切向和法向摩擦振动的同源特性。在上述研究基础上,本文对摩擦副磨合磨损过程中不同时刻的切向和法向摩擦振动信号的互相关系数进行了分析,结果表明:降噪后的切向和法向摩擦振动信号的互相关系数与摩擦系数呈现出一致的变化趋势,反映了摩擦副从磨合磨损到稳定磨损的变化。
[Abstract]:The friction vibration is friction wear side a physical phenomenon occurred in the process of surface asperity collisions, is one of the output characteristics of tribology system, contains the friction wear process reflects the vice tribology information and dynamical information. However, the friction vibration is a weak signal with low SNR, often submerged in strong background noise the change is difficult to reflect the wear state, so how to realize the extraction and identification of friction vibration signal is very important. The correlation analysis is the study of mutual dependency relation between the signals, and can be used for signal recognition and extraction. The friction and wear process of surface asperity collisions can be excited at the same time to the normal and tangential friction vibration, two for the homologous signal, have certain dependency relation. Therefore, the relationship between the tangential and normal friction vibration can provide a new idea for the identification and extraction of friction vibration The road. This paper takes reciprocating sliding friction wear of friction vibration signals collected in the trial as the research object, the correlation based on cross-correlation theory of friction vibration signal is studied, the main research contents and conclusions are as follows: firstly, based on cross-correlation theory is analyzed, the friction vibration signal containing noise acquisition test process the results show that the noise to the normal and tangential friction vibration signals with time delay, the relationship between the number of small, low degree of correlation. Therefore, the noise signal can not reflect the characteristics and method to cut homologous to friction and vibration. In order to eliminate the influence of noise, the application of harmonic wavelet packet transform theory of friction vibration signal the acquisition of the extracted signal noise, friction vice state change of running in wear, and has carried on the correlation analysis results show that the noise reduction to the normal and tangential friction vibration Dynamic signals without time delay, correlation coefficient, correlation degree is high. Therefore, the harmonic signal after wavelet packet de-noising reflects the tangential and normal homologous characteristics of friction vibration. On the basis of the above study, this paper at different times in the process of friction wear side cut each other to the relationship and normal friction vibration the number of signal are analyzed. The results show that the denoised tangential and normal cross-correlation coefficient and friction coefficient of the friction vibration signal showing the same trend, reflecting the friction wear to change from stable wear.

【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH117.1

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