曲轴平衡率对主轴承润滑特性的影响  

Effects of the Crankshaft Balance Rate on the Lubrication Characteristics of Main Bearings

作　　者：章朝栋 赵俊生[1] 朱桂香 李涵 李正文 Zhang Chaodong;Zhao Junsheng;Zhu Guixiang;Li Han;Li Zhengwen(College of Mechanical Engineering,North University of China,Taiyuan 030051,China;State Key Laboratory of Engine Reliability,Weichai Power Company Limited,Weifang 261061,China)

机构地区：[1]中北大学机械工程学院,山西太原030051 [2]潍柴动力股份有限公司内燃机可靠性国家重点实验室,山东潍坊261061

出　　处：《内燃机学报》2020年第2期178-184,共7页Transactions of Csice

基　　金：内燃机可靠性国家重点实验室开放基金资助项目(SKLER-201903).

摘　　要：针对某型柴油机功率提升后主轴承润滑性能恶化的现象,考虑轴颈与轴瓦表面粗糙度、曲轴与轴承座弹性变形的影响,建立了12 V90°柴油机主轴承的润滑分析计算模型.根据弹性流体动力润滑、轴承动力学及平衡率计算理论,分析了不同曲轴平衡率对主轴承的润滑性能的影响.采用正交试验研究了平衡率、轴承宽度及轴承间隙对最小油膜厚度、最大油膜压力、平均摩擦损失功和峰值粗糙接触压力的影响,并提出了改进方案.结果表明:曲轴平衡率对主轴承润滑性能有很大的影响,对最小油膜厚度、最大油膜压力和峰值粗糙接触压力的影响权重与轴承间隙相接近,均低于轴承宽度;平衡率对平均摩擦损失功的影响权重最大;相比轴承宽度、轴承间隙等影响因素,曲轴平衡率在强化柴油机主轴承润滑设计阶段也应重点考虑.In order to improve the lubrication characteristic of main bearings of 12 V90°diesel engine after its power output was enhanced,a lubrication analysis model of the main bearings was established in which the surface roughness of the journal and the bearing shell,and the influence of the elastic deformation of the crankshaft and the bearing blocks were considered.The influences of different balance rates on the crankshaft lubrication performance were analyzed according to theories of elasto-hydrodynamic(EHD)lubrication and bearing dynamics.Effects of the balance rate,bearing width and radial clearance on the minimum film thickness,maximum film pressure and friction loss power were analyzed by using orthogonal simulation design,and then an improvement proposal was suggested.The results show that the balance rate of the crankshaft has a great influence on the lubrication performance of the main bearings.The influence weights of the minimum oil film thickness,the maximum oil film pressure and the peak asperity contact pressure are close to that of the radial clearance,but lower than that of the bearing width.Moreover,the balance rate has the greatest influence on the average friction loss.Compared with influence factors of the bearing width,the radial clearance and others,the influence factor of the crankshaft balance rate should also be considered during the lubrication design stage of the main bearings when the diesel engine power is intensified.

关 键 词：柴油机 弹性流体动力润滑 曲轴平衡率 主轴承 

分 类 号：TK402[动力工程及工程热物理—动力机械及工程]