当盘轴松动时，油膜涡动会对转轴的运动轨迹造成影响，从而影响转盘和转轴的碰摩，转盘和转轴的碰摩又会对油膜涡动造成很大扰动，非稳态油膜力对转子系统盘轴松动故障的影响具有重要研究价值。本文利用Hertz接触理论和非稳态非线性油膜力建立了盘轴松动故障转子-轴承系统的运动微分方程，利用四阶龙格-库塔法对其进行数值仿真，并经过实验验证。讨论了非稳态油膜力对转盘转动状态的影响及油膜间隙对转子系统振动特性的影响。研究结果表明：转盘无量纲转速有高低两种状态，不考虑油膜力的转子系统转盘转速进入高转速状态时，转轴转速低于考虑油膜力的转子系统；随油膜间隙增大，轴承端的运动轨迹经历类似周期运动状态、混乱状态、类似周期运动状态，运动轨迹的形状变得越来越细长，转轴中心的运动轨迹像一个不断旋转的扇形，无明显变化规律，系统的频率成分基本无变化，但各频率成分的幅值会有不同的变化。研究成果对盘轴松动故障的建模及动力学特性研究具有重要的参考价值。
Abstract
When disk and shaft of a rotor system are loose, oil whirl can affect shaft motion trajectory, and lead to rubbing between disk and shaft, this rubbing can cause large disturbance to oil whirl, so study on effects of unsteady oil film force on rotor system with loose disk and shaft is valuable.Here, dynamic differential equations of a rotor-bearing system with loose disk and shaft were established with Hertz impact-contact theory and unsteady and nonlinear oil film force.The fourth-order Runge-Kutta method was used to solve these equations, and the numerical simulation results were verified with tests.The effects of unsteady oil film force on disk rotating state and effects of oil film clearance on vibration characteristics of the rotor system were discussed.The results showed that disk dimensionless rotating speed has two states of high rotating speed and low one; when the rotor system does not consider oil film force and its disk rotating speed enters high speed state, its shaft rotating speed is lower than that of the rotor system considering oil film force; with increase in oil film gap, bearing center motion trajectory undergoes quasi-periodic motion state, chaos one and quasi-periodic one, and its shape becomes more and more slender; shaft center motion trajectory is like a rotating sector without obvious variation law, frequency components of the rotor system are basically unchanged, but their amplitudes have different changes; the study results provide an important reference for modeling of rotor systems with loose disk and shaft and studying their dynamic characteristics.
关键词
盘轴松动 /
非线性振动 /
Hertz接触 /
故障诊断 /
非稳态油膜力
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Key words
rotors with loose disc /
nonlinear vibration /
hertz contact /
fault diagnosis /
unsteady oil film force
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参考文献
[1] Chu F, Tang Y. Stability and non-linear responses of a rotor-bearing system with pedestal looseness[J]. Journal of Sound & Vibration, 2001, 241(5):879-893.
[2] Lu W X, Chu F L. Experimental Investigation of Pedestal Looseness in a Rotor-Bearing System[J]. Key Engineering Materials, 2009, 413-414:599-605.
[3] 张靖, 闻邦椿. 两端支座松动转子系统的频率特性分析[J]. 中国机械工程, 2008, 19(1):68-71.
ZHANG Jing, WEN Bang-chun. A Study of Frequency Characteristics of Rotor System with Pedestal Looseness at Two Supports [J]. China Mechanical Engineering, 2008, 19(1):68-71.
[4] 张靖, 闻邦椿. 带有两端支座松动故障的转子系统的振动分析[J]. 应用力学学报, 2004, 21(3):67-71.
ZHANG Jing, WEN Bang-chun. Vibration characteristics of a Rotor System with Pedestal Looseness at Two Supports [J]. Chinese Journal of Applied Mechanics, 2004, 20(3): 67-71.
[5] Lu Y J, Ren Z H, Chen H, et al. Study on Looseness and Impact - Rub Coupling Faults of a Vertical Dual-Disk Cantilever Rotor- Bearing System[J]. Key Engineering Materials, 2007, 353-358(4):2479-2482.
[6] 刘长利,郑建荣,周炜,闻邦椿.松动裂纹转子轴承系统周期运动分岔及稳定性分析[J].振动与冲击,2007(11):13-15+24+180.
LIU Chang-li, ZHENG Jian-rong, ZHOU Wei, et al. 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(11):13-15+24+180.
[7] 王宗勇,吴敬东,闻邦椿.支承松动的质量慢变转子系统混沌特性研究[J].中国机械工程,2005(02):73-76.
WANG Zong-yong, WU Jing-dong, WEN Bang-chun. Study on Chaos Behaviors of Rotor Systems with Slow-varying Mass and Pedestal Looseness[J]. China Mechanical Engineering,2005(02):73-76.
[8] 王宗勇, 吴敬东, 闻邦椿. 质量慢变转子系统的松动与碰摩故障研究[J]. 振动工程学报, 2005, 18(2):167-171.
WANG Zong-yong, WU Jing-dong, WEN Bang-chun. Research on pedestal looseness and rub-impact faults of rotor system with slowly varying mass [J]. Journal of Vibration Engineering, 2005, 18(2):167-171.
[9] 王宗勇, 吴敬东, 闻邦椿. 质量慢变转子-滚动轴承系统的支承松动故障分析[J]. 中国机械工程, 2005, 16(13):1197-1200.
WANG Zong-yong, WU Jing-dong, WEN Bang-chun. Study on Pedestal Looseness Faults of a Rotor-roll Bearing System with Slowly Varying Mass [J]. China Mechanical Engineering, 2005, 16(13):1197-1200.
[10] Behzad M, Asayesh M. Vibration analysis of rotating shaft with loose disk, IJE Transactions B: Applications, 2002, 15(4): 385-393.
[11] Behzad M, Asayesh M. Numerical and experimental investigation of the vibration of rotors with loose discs, Proc. IMechE Part C: J. Mechanical Engineering Science,2010, 224:85-94.
[12] Zhang W, Xu X F. Modeling of Nonlinear Oil-Film Force Acting on a Journal with Unsteady Motion and Nonlinear Instability Analysis under the Model[J]. International Journal of Nonlinear Sciences and Numerical Simulation, 2000, 1(3: 179-186.
[13] 张文,崔升,徐小峰,等. 动载轴承非稳态非线性油膜力的一般数学模型[A]. 见王大钩,曲广吉编. 工程力学进展[M]. 北京: 北京大学出版社, 1998, 158-167.
ZHANG Wen, CUI Sheng, XU Xiao-feng, et al. General mathematical model of instable, nonlinear oil-film force acting on a dynamic load bearing[A] .Wang D J , Qu G J , eds .Advanced Engineering Mechanics[ M] .Beijing :Peking University Press , 1998 .158 -167 .
[14] 张彦梅,陆启韶. 非稳态油膜力作用下转子振动的分岔与稳定性分析[J]. 航空学报,2003,(01):36-38.
ZHANG Yan-mei, LU Qi-shao. Bifurcation and Stability Analysis on Vibrations of Rotor Systems with Unsteady Oil Film Force [J]. Acta Aeronautica Et Astronautica Sinica,2003,(01):36-38.
[15] 徐小峰,张文. 一种非稳态油膜力模型下刚性转子的分岔和混沌特性[J]. 振动工程学报,2000,(02):91-97.
XU Xiao-feng, ZHANG Wen. Bifurcation and Chaos of Rigid Unbalance Rotor in Short Bearings under an Unsteady Oil-Film Force Model [J]. Journal of Vibration Engineering,2000,(02):91-97.
[16] 杨绪灿，金建三.弹性力学[M].北京:高等教育出版社，1987.188-201.
YANG Xu-can JIN Jian-san. Elasticity [M]. Beijing: Higher Education Press, 1987. 188-201.
[17] Timoshenko S, Goodier J N. Theory of Elasticity [M], McGraw Book Company, Inc. 1951:377-379.
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