A comprehensive survey of the analytical, numerical and experimental methodologies for dynamics of multibody mechanical systems with clearance or imperfect joints

Simulation of journal bearing friction in severe mixed lubrication – Validation and effect of surface smoothing due to running-in

Multi-objective optimization of surface textured journal bearing by Taguchi based Grey relational analysis

A study of friction in worn misaligned journal bearings under severe hydrodynamic lubrication

Theoretical and experimental investigation on the influences of misalignment on the lubrication performances and lubrication regimes transition of water lubricated bearing

Journal bearing friction pair system is one of the most general and essential parts used in various mechanical devices. A special test bench is developed for the study on lubrication performance of cylindrical journal bearings. The effect of journal misalignment as a result of shaft bending under load is studied. The results show obvious changes at distribution and value of oil film pressure, oil film thickness and oil temperature of journal bearing due to journal misalignment. The higher the load on the shaft, the larger the journal misalignment resulted from shaft deformation, the more obvious effect on lubrication performance of journal bearing.

An Experimental Study of Journal Bearing Lubrication Effected by Journal Misalignment as a Result of Shaft Deformation Under Load

Journal misalignment exists generally in journal bearings. When severe journal misalignment takes place, the minimum film thickness of journal bearings reduces greatly. In this condition, the surface roughness, the oil viscosity-pressure relationship (VPR), and the thermal effect have obvious effects on hydrodynamic lubrication performance of misaligned bearings. In this paper, the oil film pressure, oil film temperature, load-carrying capacity, end leakage flow rate, frictional coefficient, and misalignment moment of a journal bearing with different angles of journal misalignment and surface roughness, and considering oil VPR and thermal effect, were calculated based on the generalized Reynolds equation, energy equation, and solid heat conduction equation. The results show that the oil VPR and surface roughness have a significant effect on the lubrication of misaligned journal bearings under large eccentricity ratio. The thermal effect will affect obviously the lubrication of misaligned journal bearings when eccentricity ratio and angle of journal misalignment are all large. In the present design, the size of the journal bearing is compact more and more, and the eccentricity ratio and angle of journal misalignment are usually large in operating conditions. Therefore, it is necessary to take the effects of journal misalignment, surface roughness, oil VPR, and thermal effect into account in the design and analyses of journal bearings.

Thermohydrodynamic Lubrication Analysis of Misaligned Plain Journal Bearing With Rough Surface

A method to analyse lubrication performance of journal bearing considering journal misalignment caused by shaft deformation under rotating load in a shaft-bearing system was established and validated by special experiments on a developed experimental rig of journal bearing. The experimental results show that the proposed analytical formulation and method can meet the researching requirements. Oil film pressure, end leakage flowrate, and friction coefficient of journal bearing at variant journal misalignment caused by shaft deformation under rotating load were calculated. The results show that journal misalignment makes obvious difference to distribution of film pressure and film thickness. The maximum film pressure increases markedly. The minimum film thickness reduces. End leakage flowrate increases. Friction coefficient of journal slightly changes. Therefore, in order to make the calculation of journal bearing more realistic and to achieve more reasonable design in shaft-bearing system, the infl...

Influence of Journal Misalignment Caused by Shaft Deformation under Rotational Load on Performance of Journal Bearing

Purpose – Current lubrication analyses of misaligned journal bearings were generally performed under some given preconditions. To make the lubrication analysis closer to the actual situation and usable to the journal bearing design, the purpose of this paper was to calculate the lubrication characteristics of misaligned journal bearings considering the viscosity-pressure effect of the oil, the surface roughness and the elastic deformation of the journal bearing at the same time. Design/methodology/approach – The lubrication of bearings was analyzed using the average Reynolds equation. The deformation of the bearing surface under oil film pressure was calculated by a compliance matrix method. The compliance matrix was established by finite element analysis of the bearing housing. The viscosity-pressure and viscosity–temperature equations were used in the analysis. Findings – The oil viscosity-pressure relationship has a significant effect on the lubrication of misaligned journal bearings. The surface rough...

Effect of surface roughness, viscosity-pressure relationship and elastic deformation on lubrication performance of misaligned journal bearings

There is direct interaction between crankshaft and bearing in an internal combustion engine. The effect of lubrication status of bearing was not considered in the present calculation of crankshaft strength. A given oil film pressure distribution of bearing was generally used as load acted on journal. In this paper, a crankshaft-bearing system was taken as the study object. On the basis of lubrication analysis of misaligned bearing caused by crankshaft deformation, the stress and strength of-crankshaft were calculated using analytical oil film pressure of bearing as the load boundary condition. Crankshaft deformation and bearing load were calculated by whole crankshaft beam-element method. The lubrication of crankshaft bearing was analyzed by the kinetics method. Crankshaft stress was calculated by the finite-element method. The results show that when the effect of crankshaft deformation under load is considered, the offset distribution of oil film pressure of bearing appears and the highest oil film pressure increases remarkably, which result in the stresses of local area on fillet surface of crankshaft journal increase obviously and the safety factor of crankshaft decreases.

Jun Sun

Papers

An Experimental Study of Journal Bearing Lubrication Effected by Journal Misalignment as a Result of Shaft Deformation Under Load

Thermohydrodynamic Lubrication Analysis of Misaligned Plain Journal Bearing With Rough Surface

Influence of Journal Misalignment Caused by Shaft Deformation under Rotational Load on Performance of Journal Bearing

Effect of surface roughness, viscosity-pressure relationship and elastic deformation on lubrication performance of misaligned journal bearings

Effect of Lubrication Status of Bearing on Crankshaft Strength