波动载荷对直齿轮微观热弹流润滑的影响

The Influence of Fluctuating Load on Micro Thermal Elastohydrodynamic Lubrication of Spur Gears

根据实测表面形貌数值拟合了一表面形貌函数,计入了波动载荷效应,考虑了表面粗糙度、时变效应和热效应,对直齿轮进行了微观热弹流润滑研究,分析了载荷波动频率和载荷波动幅值对油膜压力、膜厚和温度的影响。结果表明:低频波动载荷对压力、膜厚和最大温度影响较大,波动载荷频率较高时中心油膜压力、中心膜厚、最小膜厚和最大温度基本不受波动频率影响;较低波动频率下双齿啮合变单齿啮合瞬时的接触区中心位置的瞬态温升较大,载荷波动频率的增大引起节点接触区入口处温升减小,随着波动频率的增大节点处接触中心位置的瞬态温升增大明显;载荷波动幅值较大时,接触区中心油膜压力、中心膜厚、最小膜厚和最大温度波动幅度较大。

According to the measured surface topography an appropriate function of surface topography was numerically simulated. Investigations on the micro thermal elastohydrodynamic lubrication of spur gears were achieved considering fluctuating load effect,surface roughness,time-variant effect and thermal effect. Influences of load fluctuation frequency and load fluctuation amplitude on film pressure,film thickness and temperature were analyzed. Results show that low load fluctuation frequency affects film pressure,film thickness and the maximum temperature a lot.High load fluctuation frequency makes little difference to centre film pressure,centre film thickness,the minimum film thickness and the maximum temperature. Transient temperature rise in contact region center at double tooth meshing change single tooth meshing transient under high load fluctuation frequency condition is great. Increase of load fluctuation frequency may cause temperature rise in pitch point inlet zone decrease. High load fluctuation frequency makes great contribution to enormous transient temperature rise in pitch point contact region centre. When load fluctuation amplitude is larger centre film pressure,centre film thickness,the minimum film thickness and the maximum temperature fluctuation range is wide.