表面粗糙度对滚珠式三叉杆万向联轴器弹流润滑性能的影响

Influence of Surface Roughness on Elastohydrodynamic Lubrication Performances of Ball-type Tripod Universal Joint

为揭示表面粗糙度对滚珠式三叉杆万向联轴器润滑性能的影响机制,利用高斯随机粗糙表面来表征摩擦副实际接触表面,建立考虑表面粗糙度的等效点接触弹流润滑模型,采用有限差分法和多重网格技术求解Reynolds方程得到油膜压力和接触区弹性变形;通过ANSYS软件建立次表面应力有限元求解模型,分析表面粗糙度参数和表面纹理方向对联轴器弹流润滑性能的影响。结果表明:随着表面粗糙度均方根的增大,接触区内的油膜压力和膜厚波动幅值增大,同时次表面高应力区域逐渐向上表面移动接近接触表面层;随着波长因子的增大,接触区内的油膜压力呈现明显的纹理方向分布,次表面应力出现明显的波动;相较于横向表面纹理方向,纵向表面纹理方向对联轴器润滑性能的影响较大。

To reveal the influence mechanism of surface roughness on the lubrication performance of ball-type tripod universal joint,the Gaussian random rough surface was adopted to represent the actual surface of the friction pair,and an equivalent point-contact elastohydrodynamic lubrication model considering surface roughness was established.The finite difference method and multi-mesh technique were used to solve Reynolds equation to obtain oil film pressure and elastic deformation in the contact area.The finite element model of the subsurface stress was established by ANSYS software,and the influence of surface roughness parameters and surface texture direction on elastohydrodynamic lubrication of the joint was analyzed.The results show that with the increase of root mean square of surface roughness,the fluctuation amplitude of oil film pressure and film thickness in the contact area increases,while the high stress area on the secondary surface gradually moves up the surface and approaches the contact surface.With the increase of wavelength factor,the oil film pressure in the contact area shows obvious texture direction distribution,and the subsurface stress shows significant fluctuations.Compared with the transverse surface texture direction,the longitudinal surface texture direction has a greater influence on the lubrication performance of the joint.