Application of weighted contribution rate of nonlinear output frequency response functions to rotor rub-impact

Abstract The rub-impact between a rotor and a stator is a common fault of the rotor system. Various methods are available to detect the rub impact using vibration signals. However, the noise in vibration signals causes inconvenience when extracting characteristic signals. Nonlinear output frequency response functions (NOFRFs) comprise an effective method for using input and output signals to detect damage of a structure or system. A new evaluation method named the NOFRFs weighted contribution rate has been proposed in this paper. This method is an extension of traditional NOFRFs-based indexes and attempt to obtain a new index with higher recognition of faults. As a new index extracted by this method, the second-order optimal weighted contribution rate of the NOFRFs optimally amplify the extracted fault features. The characteristic signal after amplification is significantly enhanced. The new index is applied to the evaluation of a rub-impact fault. The simulation and experimental results demonstrate the sensitivity of the new index to rub-impact faults. Especially in the initial stage of the occurrence of rub-impact, the new index shows better superiority. The findings demonstrated that the second order optimal weighted contribution rate has a high application value in the fault diagnosis of rub-impact.

[1]  Z. Lang,et al.  Detecting the position of non-linear component in periodic structures from the system responses to dual sinusoidal excitations , 2007 .

[2]  Yang Yong-feng,et al.  Dynamic characteristics of cracked uncertain hollow-shaft , 2019, Mechanical Systems and Signal Processing.

[3]  Ashish K. Darpe,et al.  Investigations on bending-torsional vibrations of rotor during rotor-stator rub using Lagrange multiplier method , 2017 .

[4]  Jianfu Cao,et al.  Fault diagnosis of complex system based on nonlinear frequency spectrum fusion , 2013 .

[5]  Jin Chen,et al.  Experimental validation of impact energy model for the rub–impact assessment in a rotor system , 2011 .

[6]  Pietro Borghesani,et al.  A statistical methodology for the design of condition indicators , 2019, Mechanical Systems and Signal Processing.

[7]  S. Billings,et al.  Output Frequency Characteristics of Nonlinear Systems , 1996 .

[8]  Xin Xia,et al.  A novel method for fault diagnosis of hydro generator based on NOFRFs , 2015 .

[9]  Hongrui Cao,et al.  Mechanical model development of rolling bearing-rotor systems: A review , 2018 .

[10]  Stephen A. Billings,et al.  Output frequency response function of nonlinear Volterra systems , 2006, Autom..

[11]  Xinxin Li,et al.  Study of cumulative fatigue damage detection for used parts with nonlinear output frequency response functions based on NARMAX modelling , 2017 .

[12]  Zhike Peng,et al.  Feature Extraction for Damage Detection in Structures Based on Nonlinearity Analysis , 2009 .

[13]  Hui Ma,et al.  Fixed-point rubbing fault characteristic analysis of a rotor system based on contact theory , 2013 .

[14]  Zhike Peng,et al.  Feasibility study of structural damage detection using NARMAX modelling and Nonlinear Output Frequency Response Function based analysis , 2011 .

[15]  Chao Zhou,et al.  Nonlinear dynamic response of a rub-impact rod fastening rotor considering nonlinear contact characteristic , 2016 .

[16]  S. A. Billings,et al.  Crack detection using nonlinear output frequency response functions - an experimental study , 2006 .

[17]  Dengqing Cao,et al.  Response evaluation of imbalance-rub-pedestal looseness coupling fault on a geometrically nonlinear rotor system , 2019, Mechanical Systems and Signal Processing.

[18]  S. Billings,et al.  Analysis of bilinear oscillators under harmonic loading using nonlinear output frequency response functions , 2007 .

[19]  Marian Wiercigroch,et al.  Bifurcation analysis of periodic orbits of a non-smooth Jeffcott rotor model , 2013, Commun. Nonlinear Sci. Numer. Simul..

[20]  Y. Lei,et al.  An underdamped stochastic resonance method with stable-state matching for incipient fault diagnosis of rolling element bearings , 2017 .

[21]  S. A. Billings,et al.  Energy transfer properties of non-linear systems in the frequency domain , 2004 .

[22]  Hanling Mao,et al.  The construction and comparison of damage detection index based on the nonlinear output frequency response function and experimental analysis , 2018, Journal of Sound and Vibration.