柴油机摇臂衬套弹性流体动力润滑分析

陈琳1,2，王慧辉1,2，孟丽1,2

1.内燃机可靠性国家重点实验室，山东 潍坊  261061；2.潍柴动力股份有限公司，山东 潍坊  261061

摘要：为解决供油充足时的摇臂衬套磨损故障，以某国六柴油机为研究对象，分析摇臂衬套局部承载情况，采用弹性流体动力润滑（elasto-hydrodynamic lubrication，EHD）仿真计算摇臂衬套润滑油膜厚度、摇臂衬套压力分布，提出改进方案并进行仿真和试验验证。仿真结果表明：衬套所受总压分布不均匀是衬套磨损的主要原因。增加衬套宽度后，对摇臂和衬套的仿真及试验验证结果表明：摇臂衬套压力分布均匀，衬套直径方向最大磨损量由0.336 mm减小为0.090 mm。采用EHD仿真可以在摇臂设计阶段定量预测摇臂衬套润滑情况，提高开发效率。

关键词：摇臂衬套；EHD；油膜厚度；粗糙接触

Elasto-hydrodynamic lubrication analysis of rocker arm bushing of diesel engine

CHEN Lin1,2, WANG Huihui1,2, MENG Li1,2

1.State Key Laboratory of Engine Reliability, Weifang 261061, China;2.Weichai Power Co., Ltd., Weifang 261061, China

Abstract：In order to solve the wear failure of the rocker arm bushing when the fuel supply is sufficient, the local load condition of the rocker arm bushing is analyzed and the elasto-hydrodynamic lubrication (EHD) simulation is used to analyze the thickness of the rocker arm bushing lubricating oil film and the pressure distribution of the rocker arm bushing, and an improved scheme is proposed for simulation and test verification. The simulation results of the original rocker arm bushing show that the distribution of the total pressure on the bushing is uneven, which is main cause of bushing wear. After increasing the width of the bushing, the simulation and test results of rocker arm bushing show that the pressure on the bushing is evenly distributed, and the maximum wear in the diameter direction of the bushing is reduced from 0.336 mm to 0.090 mm. EHD simulation can be used to quantitatively predict the lubrication of the rocker arm bushing at the rocker arm design stage and improve the development efficiency.

Keywords:rocker arm bushing; EHD; oil film thickness; asperity contact