针对滚动轴承试验机的陪试轴承——推力滑动轴承承受瞬时冲击载荷这一问题，建立了推力轴承-转子系统的动力学模型和简化的轴承座结构变形模型，运用有限元法求解雷诺方程，欧拉积分法求解转轴的轴向动力学方程，ANSYS仿真获得轴承座的结构变形量，通过联合求解，得到了冲击过程中推力轴承油膜合力、最小油膜厚度和流量随时间的变化情况，对比了考虑和不考虑轴承座结构变形时推力轴承的冲击响应。结果发现：轴承座弹性变形对油膜合力和最小油膜厚度的影响不可忽略。不考虑结构变形时，油膜合力和最小油膜厚度的响应速度快得多，响应时间大约快了22%。弹性变形延缓了响应过程，起到了缓冲作用，并且缩短了达到稳态时所需的时间。考虑和不考虑弹性变形时，油膜合力的最大值和最小油膜厚度的最小值基本相同。分析表明，合适的轴承座结构刚度可以提高推力轴承的抗冲击能力。结构刚度不能小于某个临界值，太小可能造成某一瓦块的最小油膜厚度非常小，难以承受大的瞬时冲击载荷；同时也不能太大，不仅结构复杂，而且起不到缓冲的效果，可能会造成某些连接件过早失效。
Abstract
Here, aiming at a thrust sliding bearing of a rolling bearing testing machine subjected to transient impact load, the dynamic model for the thrust bearing-rotor system and the simplified bearing pedestal structural deformation model were established. Reynolds equation for thrust bearing oil film was solved with the finite element method, the axial dynamic equation of the rotating shaft was solved using Euler integral method, and the structural deformation of bearing pedestal was solved with ANSYS simulation. Through the combined solving, variations of the thrust bearing’s oil film resultant force, minimum oil film thickness and flow rate with time varying in impact process were obtained. Impact responses of the thrust bearing considering and not considering structural deformation of bearing pedestal were compared. The results showed that effects of bearing pedestal elastic deformation on oil film resultant force and minimum oil film thickness can’t be ignored; without considering structural deformation, response speeds of oil film resultant force and minimum oil film thickness are much faster, and their response time decreases by about 22%; elastic deformation delays response process, it acts as a buffer and shortens the time required to reach the system’s steady state; when elastic deformation is considered or not, the maximum value of oil film resultant force and the minimum value of the minimum oil film thickness are basically the same; appropriate structural stiffness of bearing pedestal can improve the anti-impact ability of thrust bearing; the structural stiffness should not be less than a certain critical value, too small structural stiffness may cause the minimum oil film thickness of a certain tile to be very small and hard to bear large transient impact load; too large structural stiffness may cause bearing pedestal structure to be complex without buffering effect, and some connectors to fail too early.
关键词
推力轴承 /
抗冲击 /
结构弹性变形 /
响应分析
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Key words
thrust bearing /
impact resistance /
structural elastic deformation /
response analysis
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参考文献
［1］KENNEDY J S, SABHAPATHY P, RODKIEWICZ C M. Transient thermal effects in an infinite tilted-pad slider bearing［J］. Tribology Transactions, 1989, 32(1):47-53.
［2］富彦丽, 马希直, 朱均. 圆轴承三维热流体动力润滑的研究［J］. 航空动力学报, 2002(4):86-91.
FU Yanli, MA Xizhi, ZHU Jun. Three-dimensional thermohydrodynamic analysis of circular journal bearing ［J］. Journal of Aerospace Power, 2002(4):86-91.
［3］TICHY J, BOU-SAD B. Hydrodynamic lubrication and bearing behavior with impulsive loads［J］. Tribology Transactions, 1991, 34(4): 505-512.
［4］RAO T V V L N, BISWAS S, HIRANI H et al. An analytical approach to evaluate dynamic coefficients and nonlinear transient analysis of a hydrodynamic journal bearing［J］. Tribology Transactions, 2000, 43(1):109-115.
［5］马希直，朱均. 阶跃载荷扰动条件下推力轴承热瞬态过程研究［J］. 润滑与密封, 2009, 34(1):43-45.
MA Xizhi, ZHU Jun. Thermal transient behavior of thrust bearing under step applied load［J］. Lubrication Engineering, 2009, 34(1):43-45.
［6］马希直，朱均. 载荷扰动下滑动推力轴承绝热瞬态过程分析［J］. 润滑与密封, 2009,34(3):49-52.
MA Xizhi, ZHU Jun. A Study on adiabatic transient behavior of thrust bearing under dynamic operating load［J］. Lubrication Engineering, 2009,34(3):49-52.
［7］张胜伦，裴世源，徐华，等. 考虑瞬态冲击和弹性变形的滑动轴承特性与动力学响应［J］. 西安交通大学学报, 2018, 52(1): 100-106.
ZHANG Shenglun, PEI Shiyuan, XU Hua， et al. Journal bearing properties and dynamic responses under transient impact load and elastic deformation［J］. Journal of Xi’an Jiaotong University, 2018, 52(1): 100-106.
［8］张直明. 滑动轴承的流体动力润滑理论［M］.北京：高等教育出版社，1986.
［9］杨沛然. 流体润滑数值分析［M］.北京：国防工业出版社，1998.
［10］戚社苗，耿海鹏，虞烈. 动压气体轴承性能计算方法研究［J］. 机械强度, 2006, 28(3): 369-373.
QI Shemiao, GENG Haipeng, YU Lie. New method for the calculation of the characteristics of aerodynamic bearings［J］. Journal of Mechanical Strength, 2006, 28(3): 369-373.
［11］HANG P. Numerical calculation of elastohydrodynamic lubrication［M］.Numerical Calculation of Elastohydrodynamic Lubrication. Singapore: John Wiley & Sons Singapore Pte Ltd, 2015.
［12］胡仁喜，康士廷. ANSYS 190有限元分析从入门到精通［M］.北京：机械工业出版社,2019.
［13］邢家省, 杨义川, 王拥军. 一类欧拉积分公式的计算方法及应用［J］. 四川理工学院学报(自然科学版), 2019, 32(1):87-93.
XING Jiasheng, YANG Yichuan, WANG Yongjun. Calculation method and application of a class of euler’s integral formula［J］. Journal of Sichuan University of Science ＆ Engineering( Natural Science Edition), 2019, 32(1):87-93.
［14］彭龙龙，汪久根，洪玉芳，等. 初始条件与突变载荷对径向滑动轴承瞬态润滑性能的影响［J］. 润滑与密封, 2015, 40(7): 19-34.
PENG Longlong, WANG Jiugen, HONG Yufang， et al. Effects of initial conditions and impact load on transient lubrication behavior of journal bearings［J］. Lubrication Engineering, 2015, 40(7): 19-34.
［15］周星, 伍鹤皋, 苏凯. 混流式水轮机轴向水推力研究综述和讨论［J］.水利学报, 2019, 50(10):1242-1252.
ZHOU Xing, WU Hegao, SU Kai.Overview and discussion on hydraulic axial thrust in francis turbine research［J］. Journal of Hydraulic Engineering, 2019, 50(10):1242-1252.
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