高速滚动轴承用TiNi60合金的润滑性能及油气润滑两相流流型的数值计算

摘要

The friction and wear tests were performed using Nitinol 60 alloy pin sliding over GCr15 steel disk in a pin-on-disk tribometer system under PAO oil lubrication conditions.It was found that Nitinol 60 alloy can be lubricated well and has shown remarkable tribological performance.Average coefficient of friction (COF) of Nitinol 60 is 0.6 under dry friction; however,average COF decreases to 0.1 under PAO oil lubrication.SEM image of the worn surface shows that Nitinol 60 exhibits excellent wear resistance and the wear mechanism is mainly adhesive wear.Flow pattern of oil-air flow in oil pipe was simulated by FLUENT software with VOF model for acquiring working performance of oil-air lubrication.The optimum velocity of oil and air at the inlet was achieved,which provides the great proposal for the design of experiment of oil-air lubrication of Nitinol 60 alloy.The simulation results showed that the optimum annular flow of flow pattern was obtained when air velocity is 10 m/s and oil velocity is 0.05 m/s.The formation mechanism of annular flow was also discussed in the present study.%销-盘摩擦磨损实验研究表明:TiNi60合金在PAO油润滑下具有优异的摩擦学性能,稳定阶段的平均摩擦系数由干摩擦的0.6降低到油润滑下的0.1,而且非常稳定.从SEM磨损形貌图可知:油润滑下TiNi60合金的磨损表面光滑,粘着磨损明显减弱.在实际研究中,仿真计算是获得高速滚动轴承在油气润滑下各项工作性能数据的有效方法.采用FLUENT数值计算了油-气两相流在水平管子内的流型分布,得到了最佳油、气的进口速度,为高速滚动轴承用riNi60合金在油气润滑下的使用提供了理论依据.仿真计算结果表明:当空气速度为10 m/s和油速度为0.05 m/s时,可以得到最佳的环状流型分布.