直线度误差对活塞销轴承润滑性能的影响

Effect of Straightness Error on Lubrication Performance for Piston Pin Bearing

基于Reynolds润滑方程和油膜厚度方程,研究了直线度误差对轴承润滑性能的影响,建立了轴向几何型线的数学表达公式;针对某高速大功率柴油机,建立了详细的单缸计算分析仿真模型;研究了锥形、喇叭形、桶形和三角形误差对活塞销轴承的最小油膜厚度、最大油膜压力、轴瓦最大摩擦力矩、平均摩擦功损失以及油膜温度变化曲线和温度场分布的影响规律。研究结果表明:不同活塞销直线度误差的素线形状对轴承润滑性能的影响不同,素线形状的极值点位置对活塞销动态特性和轴承润滑性能的影响较大,素线曲率的影响要小些;使活塞销素线形状失去对称性,或使活塞销刚度减小的误差,对轴承润滑不利,有导致衬套脱落、烧蚀的危险。

:Based on the Reynolds lubrication and oil film thickness equations ,the effect of straightness error on the bearing lu-brication performance was studied and the mathematical expression formula of axial geometric lines was set up .For a high speed and high power diesel engine ,the detailed single cylinder calculation simulation model was established .The influences of coning error ,horn error ,bucket error and triangle error on the minimum oil film thickness ,the maximum oil pressure ,the maximum friction moment ,the average friction power loss ,the oil film temperature curve and distribution of piston pin bearing were studied .The results show that the prime line shapes of different piston pin straightness errors have different influences on the property of bearing lubrication .The extreme point location of prime line shape performance has greater influence on the dy-namic characteristics of piston pin and the lubrication performance of bearing compared to the curvature .The error that leads to worse symmetry of piston pin line shape or lower stiffness is adverse to bearing lubrication ,which can cause falling off or abla-tion of the bushing .