柴油机配气滚轮浮环轴承润滑特性优化研究

Optimization Research on the Lubrication Characteristics of Roller Floating Bearing of Diesel Engine Valve Train

为研究配气机构滚轮浮环衬套动态载荷、运动与润滑特性的内在联系,以某高指标船用柴油机配气机构排气滚轮浮环轴承为对象,考虑动态载荷和弹性变形,建立了润滑仿真模型。研究了浮环衬套供油、间隙匹配、浮环衬套厚度等关键结构参数对滚轮浮环轴承动态润滑特性的影响规律。结果表明:浮环衬套周向油槽能增加供油流量,但对内圈油膜厚度、油膜压力不利;浮环衬套间隙匹配对内外圈油膜影响规律不同,但优化匹配方案能有效改善油膜厚度、油膜压力、平均热载等润滑特性;适当减小浮环衬套厚度,也有利于提升润滑特性。

Taking the valve train of a heavy-duty marine diesel engine as the research object,a lubrication simulation model of exhaust roller floating bearing under dynamic load and elastic deformation was established to explore the relationship of dynamic load,fluid kinematics and lubrication characteristics for floating bearing bushing,and further study the influence of key structural parameters such as floating bushing's oil supply,clearance matching and wall thickness on the dynamic lubrication characteristics of roller floating bearing.Results show that the circumferential oil groove of floating bushing can increase oil supply flow,but it is unfavorable to the oil film thickness and transient peak oil film pressure of inner ring;The clearance matching of floating bushing has different effects on the oil film of inner and outer rings,but the optimized matching scheme can effectively improve the oil film lubrication characteristics such as oil film thickness,oil film pressure and average thermal load.Moreover,appropriately thinning the wall thickness of floating bushing is also beneficial to the lubrication characteristics.