Abstract
For the purpose of extracting the frictional vibration characteristics of the friction pair during friction and wear in different friction states, the friction and wear tests of friction pair in different friction states were conducted on a testing machine. Higher-dimensional fractal and multifractal characteristics hidden in time series can be examined by multifractal detrended fluctuation analysis (MFDFA) method. The frictional vibration time-domain signals, the friction coefficient signals and the frictional vibration frequency-domain signals were analyzed and multifractal spectra were acquired by using the MFDFA algorithm. According to the spectra, the multifractal spectrum parameters of these signals were calculated to realize the quantitative characterization of frictional vibration characteristics in different friction states. The analysis shows that it is symmetric in the variation trends of the multifractal spectrum parameters of the frictional vibration signals and the friction coefficient data. Based on the multifractal spectrum parameters of frictional vibration, the principal component analysis (PCA) algorithm was applied to establish the friction state recognition method. The results show that the multifractal spectra and their parameters can characterize the frictional vibrations, and the friction state recognition can be realized based on the multifractal spectrum parameters of frictional vibrations.
Highlights
Frictional vibration is a phenomenon caused by the friction and wear procedure of the friction pair during the operations of mechanical equipment, which contain information reflecting the characters and behaviors of the tribological system
The analysis shows that it is symmetric in the variation trends of the multifractal spectrum parameters of frictional vibrations and friction coefficients
10 and 12, some multifractal spectrum parameters are fluctuated with non-monotonical because the microscopic path of each reciprocating motion of non-monotonical variation tendency because the microscopic path of each reciprocating motion of friction pair is not repeated in the test processes, but the increasing or decreasing trends of the friction pairspectrum is not repeated in the processes, the multifractal parameters cantest be used as thebut basis forincreasing analysis. or decreasing trends of the multifractal spectrum parameters can be used as the basis for analysis
Summary
Frictional vibration is a phenomenon caused by the friction and wear procedure of the friction pair during the operations of mechanical equipment, which contain information reflecting the characters and behaviors of the tribological system. The information of tribological system include the friction coefficient [1,2], the friction torque [3], the surface morphology of the friction pair [4], the condition of the lubricating medium and the wear particles [5] These are inconvenient methods to extract the tribological characteristics by friction coefficient or friction torque, which is difficult to measure under the condition of equipment operation. The analysis of frictional vibrations is a better means to monitor the friction and wear states of the friction pair in real time during the operation of equipment. The nonlinear characteristics of frictional vibrations were analyzed by using the MFDFA algorithm to derive the multifractal spectra as well as their parameters. The analysis shows that it is symmetric in the variation trends of the multifractal spectrum parameters of frictional vibrations and friction coefficients. The research results can provide the theoretical basis and method for the real-time monitoring and fault diagnosis of mechanical equipment
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
