摘要
由于异物入侵而造成的轴瓦表面划伤是滑动轴承运行过程中的常见现象。为研究表面划痕对径向滑动轴承润滑特性的影响规律,考虑紊流、质量守恒边界等效应建立了热流体动力学润滑分析模型,采用有限元法求解了轴承的静动性能,从理论与试验角度对比了不同转速、载荷等工况下划痕对轴承润滑性能的影响规律(油膜厚度、油膜压力、温升、功耗、流量、刚度、阻尼等),探讨划痕对刚性转子系统稳定性的影响。结果表明:在静特性方面,当划痕深度与间隙达到相同量级或更高时,导致轴承最小油膜厚度显著降低,最高油膜温度升高,最大油膜压力显著增加,并引发附加弯矩;在动特性方面,划痕对轴承转子系统的刚度、阻尼、不平衡响应和稳定性均有显著影响,规律较为复杂;总体上,划痕导致转子系统临界转速降低,振幅增加,低速工况降低系统稳定性,高速工况增加稳定性。该研究对评估划痕对轴承润滑性能的影响具有一定的工程借鉴价值。
Scratches on the surface of the bearing caused by the particles is a common phenomenon in the operation of sliding bearings.To study the effect of scratches on the lubrication characteristics of radial sliding bearings,a thermo-hydrodynamic lubrication model is established based on turbulent flow and mass conservation boundaries.The static and dynamic performance of the bearing is solved by the finite element method.From the theoretical and experimental perspectives,the effect of scratches on bearing performance(oil film thickness,pressure,temperature,power consumption,flow rate,stiffness,damping,etc.)under different rotation speeds and loads is compared.The effect of scratches on the stability of the rigid rotor system is discussed.The results show that:in terms of static characteristics,when the scratch depth and the gap reach the same level or higher,the minimum oil film thickness of the bearing is significantly reduced,the maximum temperature is increased,the maximum pressure is significantly increased,and additional bending moment is induced.In terms of dynamic characteristics,scratches have a significant impact on the stiffness,damping,unbalanced response and stability of the rotor system.Generally,scratches on the surface of bearing will reduce the critical speed of the rotor system and increase the amplitude.Under low-speed conditions,scratches will reduce the stability of the rotor system,under high-speed conditions,scratches will increase stability.This study has certain engineering reference value for evaluating the effect of scratches on bearing lubrication performance.
作者
王晓红
裴世源
常山
WANG Xiaohong;PEI Shiyuan;CHANG Shan(The 703 Research Institute of CSIC,Harbin 150036;Key Laboratory of Education Ministry for Modem Design and Rotor-Bearing System,Xi'an Jiaotong University,Xi'an 710049)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2021年第11期256-264,共9页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(51975456)。
关键词
划痕
椭圆瓦轴承
润滑特性
刚度
阻尼
稳定性
scratches
elliptical bearing
lubrication characteristics
stiffness
damping
stability
