含润滑介质的正交各向异性结合面接触特性研究

Contact characteristics of orthotropic joint with lubrication medium

提出了一种含润滑介质的正交各向异性结合面法向接触刚度的分形模型。该模型基于含椭圆修正因子的Hertz接触理论,并根据考虑润滑介质的侧向泄漏的平均雷诺方程,推导出固体接触刚度与流体刚度之间的解析关系。通过分析不同因素对结合面的法向接触刚度的影响,发现当无量纲固体真实接触面积小于0.05时,结合面的法向接触刚度受流体刚度的影响较大。随着润滑介质发生侧向泄漏,固体真实接触面积逐渐增大,固体接触刚度对结合面的法向接触刚度的影响越来越显著。给定不同预紧力,对比试验与有限元仿真获得的前三阶固有频率,其最大相对误差为4.11%,证明本文构建的模型可以准确地预测结合面的接触性能。

A fractal model of normal contact stiffness of orthotropic joint with lubrication medium is proposed.The model adopts the Hertz contact theory with elliptic correction factor,and based on the mean Reynolds equation with lateral leakage of the lubrica⁃tion medium.Then,deducing the analytical relationship between the solid contact stiffness and the fluid stiffness.By means of an⁃alyzing the influence of different factors on the normal contact stiffness of joint,it is found that when the dimensionless real contact area between solids is less than 0.05,the normal contact stiffness of joint is mainly affected by fluid stiffness.With the occurrence of lateral leakage of lubrication medium,real contact area between solids is gradually large,and the influence of solid contact stiff⁃ness on the normal contact stiffness of the joint becomes more and more significant.Giving different normal preload and comparing the first three orders of natural frequencies obtained from experiments and finite element analysis,the maximum relative error be⁃tween frequencies is 4.11%,which proves that the model proposed in this paper can predict the contact performance of joint more accurately.