Lubricational Analysis Of Journal Bearing Under Three-Dimensional Movement

Internal combustion engine as a major powerplant, widely used in various areas such as national defence, transportation, industry and agriculture.Journal bearing is one of significant components of internal combustion engine (including gasoline engine, diesel engine) which has modernization, high-speed, and more compact structure. It has become one of constraints by the engine to reduce energy consumption, increase stability, increase output and efficiency. So,it is especially important for research lubricational characteristics of journal bearing under the system of internal combustion engine.Analysis of hydrodynamic lubrication of the design of journal bearing is a basic problem, theoretical studies on hydrodynamic lubrication of journal bearing has basically matured. Of late, lubricational characteristics of journal bearing is being studied more comprehensively when taking into account actual conditions (such as bearing in produce and assembly errors, surface roughness, deformation of bearing, misalignment of bearing). The theoretical basis of the existing research is basically established on Reynolds equation of two-dimensional movement without the axial motion when only consider circular motion of journal. Therefore, in some special circumstances, the axial movement of journal does exist.The author found when Professor Li Zhen, Professor He Zhixian, and Professor GUI Changlin research coupling problem between dynamics and tribology of crankshaft-bearing system of an internal combustion engine,the trajectories of crankshaft journal center are three-dimensional under actual conditions.It has three-dimensional motion of circumferential,radial and axial movement of joural. The axial movement of joural is not considered when lubrication of crankshaft-bearing is analyzed.And lubricational analysis of journal bearing which under the three-dimensional motion has not been reported.An extension of the problem about lubricational characteristics of journal bearing under two-dimension motion comes from tutorial topics.Professor Li Zhen, Professor He Zhixian and Professor GUI Changlin have established a sophisticated system of Reynolds equation under two-dimension movement of journal.On the basis of previous research, lubricational characteristics of journal bearing under three-dimensional movement is analyzed by similar method.Firstly, in this paper,the content of the field of lubrication of journal bearing and its progress are analyzed in recent years, the significance of studying lubrication of journal bearing is expounded.Secondly, this model is based on the existing journal bearing model.Counterforce of oil film of two-dimensional Reynolds equation is solved by Finite Difference Method.Some tribological performance parameters are solved.These results is calculated by programming software.Thirdly, Reynolds equation of lubricational analysis of journal bearing is proposed under three-dimensional motion of circumferential, radial and axial movement of journal. This equation on the basis of the two-dimensional Reynolds equation with axial movement.The effects of tribological characteristics of journal bearing is researched and analyzed under the axial movement of journal.Fourthly, the crankshaft bearing system of N4105I.C.E is selected as the research model. According to ADAMS simulation of multi-body dynamics model of the flexible crankshaft bearing system,shaft center parameter of journal is acquired. Lubricational program from Chapter III is invoked. Tribological characteristics of5journals is solved under three-dimensional movement,which compare with two-dimensional movement.Finally, the prime task and the innovation in this article are summarized, and some views for the further research are proposed.