微沟槽织构化三叉式万向联轴器的脂润滑特性研究

Research on Grease Lubrication Characteristics of Micro-groove Textured Tripod Universal Coupling

为减小三叉式万向联轴器的摩擦磨损和改善联轴器摩擦副的润滑性能,对主要零件滑杆建立了不同造型微沟槽的二维有限元计算模型,利用Fluent软件进行计算,研究表面织构几何形状对流体动压润滑性能的影响,并进一步研究不同空化压力下微沟槽的润滑特性。研究结果表明:空化效应的产生需要一定的临界滑移速度,且随着滑移速度的增大,空化面积不断向出口区方向扩大;计入空化效应时,微沟槽油膜压力有所下降,但油膜承载力增大,壁面摩擦力减小,其中梯形与矩形微沟槽表现出较好且相近的润滑性能;随着空化压力的增大,梯形与矩形微沟槽的油膜承载力不断增大;同一空化压力下,梯形微沟槽的油膜承载力更大,空化区域面积更小。

In order to reduce the friction and wear of the tripod universal coupling and improve the lubrication performance of the coupling friction pair,two-dimensional finite element calculation models of different micro-groove were established for the sliding bar.Fluent software was used to calculate the models and hydrodynamic pressure lubrication performance of the coupling was researched under different groove geometries and cavitation pressures.The results show that cavitation effect requires a certain critical slip velocity,and the cavitation area continues to expand towards the exit zonewith the increase of the slip velocity.When the cavitation effect is taken into account,both the oil film pressure of the micro-groove and the wall friction decreases,while the oil film bearing capacity increases.The coupling with trapezoidal and rectangular micro-groove show good and similar lubrication performance.With the increase of cavitation pressure,both the oil film bearing capacity of trapezoidal and rectangular micro-grooves increases continuously.Under the same cavitation pressure,the oil film bearing capacity of trapezoidal micro-groove is larger,and the cavitation area is smaller.