高功率密度柴油机连杆大头轴承润滑特性分析

摘要

基于全局 Newton-Raphaon 方法和柔度矩阵法对高功率密度柴油机连杆大头轴承的润滑性能进行数值摸拟；耦合求解 Reynolds 方程和弹性变形方程，比较弹性变形的连杆大头轴承与刚性轴承的轴心轨迹与压力分布。结果表明：将全局 Newton-Raphaon 方法与柔度矩阵法结合起来，对高功率密度内燃机连杆大头轴承的弹流润滑进行分析，解决了轴承偏心率大于1时弹流润滑计算难于收敛的问题；考虑表面弹性变形的连杆大头轴承与刚性轴承相比，在最大气体爆发压力附近，油膜压力分布的形状和大小明显发生变化，特别是在轴承的两端处，油膜压力明显增加并接近轴承中间部分的压力。%Based on the global Newton-Raphaon method and the flexibility matrix method,the lubrication performance of high power density diesel engine connecting-rod big-end bearing was numerically studied.Based on mass conserving boundary condition,the Reynolds equation and elastic deformation equation were solved.The orbit and the pressure distri-bution between the elastic bearing and the rigid bearing were compared.The results show that the global Newton-Raphaon method combined with flexibility matrix method solves the problem of difficult convergence of the elastohydrodynamic lubri-cation calculation as the bearing eccentricity is greater than 1 when used to analyze the elastohydrodynamic lubrication of engine connecting-rod big-end bearings under the high power density.Compared with the rigid bearing,the shape oil film pressure distribution and the size of oil film pressure of the elastic bearing are changed obviously near the maximum gas ex-plosive pressure,especially in the two ends of the bearing,the oil film pressure is increased obviously and is close to the pressure in the middle part of bearing.