- Published:
Simulations and experimental investigation on motion stability of a flexible rotor-bearing system with a transverse crack
Chinese Journal of Mechanical Engineering volume 26, pages 1194–1203 (2013)
Abstract
In the classical process for stability studies on the rotor-bearing system with crack faults, the simple discrete model is adopted for research on such problems, which neglect some needful dynamical influence factor, such as the material damping, shearing effect and gyroscopic effects, etc. Therefore, it is necessary to find a precise calculation model for simulation of the rotor-bearing system with cracks faults. In this paper, instead of the traditional simple discrete model, finite element (FE) model is adopted to investigate the motion stability of a nonlinear rotor system with crack fault. According to finite element theory, the FE model of the cracked rotor system is established firstly. It should be pointed out that the element where the crack occurs is modeled by a particular crack element and the supports at both ends are simulated by two nonlinear loads. Then, based on dimensionless and dimensionality reduction, the Newmark-β method and the shooting method are employed to study the effect of eccentricity and the depth of crack on instability speed and bifurcation feature. Furthermore, the simulation results are verified by some corresponding experiments. The simulation and experimental results show that instability speed does not change monotonically, but decreases firstly and then increases when the amount of eccentricity increases. Moreover, as the type of instability changes, the instability speed jumps concomitantly. Additionally, the presence of crack fault can disturb the oil whirl, as a result, instability speed tends to increase slightly, but it does not affect the type of instability and jumping phenomenon. This research presents an effective and convenient method which uses the finite element method (FEM) to research the motion stability of the nonlinear rotor-bearing system with cracked faults and other nonlinear force, and the proposed method can provide a theoretical reference for stability analysis and vibration control in more complex relevant rotor-bearing system.
References
GASCH R. A survey of the dynamic behavior of a simple rotating shaft with a transverse crack[J]. Journal of Sound and Vibration, 1993, 160(2): 313–332.
LEE C W. Modeling of a simple rotor with a switching crack and its experimental verification[J]. ASME Journal of Vibration and Acoustics, 1992, 114(2): 217–225.
CHAN R K, LAI T C. Digital simulation of a rotating shaft with a transverse crack[J]. Applied Mathematical Modeling, 1995, 19(7), 411–420.
MENG G, GASCH R. Stability and stability degree of a cracked flexible rotor supported on journal bearings[J]. ASME Journal of Vibration and Acoustics, 2000, 122(2): 116–125.
WAN Fangyi, XU Q, LI S, Vibration analysis of cracked rotor sliding bearing system with rotor-stator rubbing by harmonic wavelet transform[J]. Journal of Sound and Vibration, 2004, 271(3–5): 507–518.
ZHENG Jibing, MENG Guang. Analysis of the stability of a cracked rotor supported on journal bearings via chebyshev polynomials[J]. Journal of Northwestern Polytechnical University, 1997, 15(3): 383–388.
PATEL T H, DARPE A K. Vibration response of a cracked rotor in presence of rotor-stator rub[J]. Journal of Sound and Vibration, 2008, 317(3–5): 841–865.
PATEL T H, DARPE A K. Study of coast-up vibration response for rub detection[J]. Mechanism and Machine Theory, 2009, 44(8): 1 570–1 579.
LIU Changli, ZHENG Jianrong, ZHOU Wei. On the bifurcation and stability of periodic motion of rotor-bearing systems with crack and pedestal looseness fault[J]. Journal of Vibration and Shock, 2007, 26(11): 13–17.
LUO Yuegang, ZHANG Songhe, LIU Xiaodong. Stability of a two-span rotor-bearing system with crack fault[J]. Transactions of the Chinese Society for Agricultural Machinery, 2007, 38(5): 168–172.
ZHENG T, HASEBE N. An efficient analysis of high-order dynamical system with local nonlinearity[J]. Journal of Vibration and Acoustics, 1999, 121(3): 408–416.
ZHENG T, HASEBE N. Nonlinear dynamic behaviors of a complex rotor-bearing system[J]. Journal of Applied Mechanics, 2000, 67(3): 485–495.
JING Jianping, MENG Guang, SUN Yi, et al. On the non-linear dynamic behavior of a rotor-bearing system[J]. Journal of Sound and Vibration, 2004 274(3–5): 1 031–1 044.
JING Jianping, MENG G,uang SUN Yi, et al. On the oil-whipping of a rotor-bearing system by a continuum model[J]. Applied Mathematical Modelling, 2005, 29(5): 461–475.
ADILETTA G, GUIDO A R, ROSSI C. Chaotic motions of a rigid rotor in short journal bearings[J]. Nonlinear Dynamics, 1996, 10(3) 251–269.
MAYES I W. Analysis of the response of a multi-rotor-bearing system containing a transverse crack in a rotor[J]. ASME Journal of Vibration, Acoustics, Stress, and Reliability in Design, 1984, 106(2): 139–145.
LI Chaofeng, LI He, MA Hui. Bifurcation and stability of the flexible rotor-bearing system with rub-impact by a continuum model[J]. Journal of Mechanical Engineering, 2010, 46(11), 107–113. (in Chinese)
Author information
Authors and Affiliations
Corresponding author
Additional information
This project is supported by National Natural Science Foundation of China(Grant No. 51105063), and Fundamental Research Funds for the Central Universities of China(Grant Nos. N120403004, N100303001)
LI Chaofeng, born in 1980, is currently a lecturer at School of Mechanical Engineering & Automation, Northeastern University, China. He received his PhD degree from Northeastern University, China, in 2010. His main research interests include rotor dynamics, mechanical vibration and control and dynamic design of mechanical products.
YU Hexing, born in 1989, is currently a master candidate at School of Mechanical Engineering & Automation, Northeastern University, China.
ZHOU Shihua, born in 1987, is currently a master candidate at School of Mechanical Engineering & Automation, Northeastern University, China.
WEN Bangchun, born in 1930, is currently a professor at School of Mechanical Engineering & Automation, Northeastern University, China. His main research interests include vibration utilization engineering, rotor dynamics, nonlinear vibration and applications of mechanical engineering, vibration diagnostics of the machine fault, mechanical-electronic integration and the machinery engineering theories.
Rights and permissions
About this article
Cite this article
Li, C., Yu, H., Zhou, S. et al. Simulations and experimental investigation on motion stability of a flexible rotor-bearing system with a transverse crack. Chin. J. Mech. Eng. 26, 1194–1203 (2013). https://doi.org/10.3901/CJME.2013.06.1194
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.3901/CJME.2013.06.1194