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Jun Sun - One of the best experts on this subject based on the ideXlab platform.

  • Systematical Analysis Method for the Mechanical Behaviors of Crankshaft-Bearing System
    Journal of Tribology, 2016
    Co-Authors: Changlin Gui, Jun Sun
    Abstract:

    Various mechanical behaviors will happen at the same time when an engine operates. Based on this concept, in this paper, a systematical analysis method is presented to analyze the multiple mechanical behaviors (tribology, dynamics, stiffness, and strength) of the Crankshaft-Bearing system in an engine. By this method, the analyses of the tribology of Bearing, the dynamics of Crankshaft-Bearing system and the dynamic stress of Crankshaft can be accomplished simultaneously. For example, the effect of the journal misalignment of Crankshaft and the elastic deformation of Bearing bush on the dynamics of Crankshaft-Bearing system, the tribological performances of main Bearings and the dynamic stress of Crankshaft are analyzed emphatically. The results show that the journal misalignment of Crankshaft and the elastic deformation of Bearing bush have remarkable effect on the tribological performances of main Bearings and the dynamic stress of Crankshaft, but have little effect on the dynamics of Crankshaft-Bearing system.

  • Experimental Research on a Three-Dimensional Journal Orbit of a Crankshaft Bearing for an Internal Combustion Engine
    Journal of Tribology, 2014
    Co-Authors: Jun Sun, Xiao-hui Chai, Xinlong Zhu, Liang Zhang, Xianyi Wang, Wei Yin, Wei Shi
    Abstract:

    The current experimental researches on the orbit of a journal center of a Crankshaft Bearing for an internal combustion engine were usually focused on the 2D movement locus of a Crankshaft journal center in the cross section of the Bearing. However, in the actual operation of an internal combustion engine, there exists the movement of a Crankshaft journal along the Bearing axis under the effect of various factors, such as the Crankshaft deformation acted by load. Obviously the tribological performance of a Crankshaft Bearing is affected inevitably by the movement of the Crankshaft journal along the Bearing axis. In this paper, a four-stroke four-cylinder internal combustion engine was taken as the studying object, the 3D orbit (that includes the movement in the cross section of the Bearing and the movement along the Bearing axis) of the journal center of the Crankshaft Bearing for an internal combustion engine was measured under a number of operating conditions on the test bench of an internal combustion engine. The position of the journal in the Crankshaft Bearing was obtained by the measurement using eddy current gap sensors and the data post-process. The results show that there exists the movement of the Crankshaft journal along the axial direction in the Bearing for an internal combustion engine. The actual orbit of the journal center of the Crankshaft Bearing for an internal combustion engine is a 3D spatial curve. The orbit of the journal center of the Crankshaft Bearing in one operating cycle of an internal combustion engine is not a closed curve. There is relatively a large movement of the journal along the axial direction of the Crankshaft Bearing, and the numerical value of the movement is greater than the radial clearance of the Bearing. The greater the rotational speed of the internal combustion engine, the larger the amount of axial movement of the journal. The periodic variation exists in the axial movement of the Bearing journal in one operating cycle of the internal combustion engine at low engine speed, and the varying periodicity equals the number of engine cylinders. There is no obvious varying rule of the axial movement of the Bearing journal in one operating cycle of the internal combustion engine at high engine speed.

  • On the elastohydrodynamic lubrication performance of Crankshaft Bearing based on the effect of whole engine block deformation
    Industrial Lubrication and Tribology, 2012
    Co-Authors: Jun Sun, Xiaoxia Cai, Liping Liu
    Abstract:

    Purpose – The elastic deformation of Crankshaft Bearing surface will be caused when acted by oil film pressure, which will affect the lubrication performance of Crankshaft Bearing. The model of the single Bearing housing was usually used in the calculation of the elastic deformation of Bearing surface. In actual internal combustion engine, the main Bearing housing is combined together with engine block; deformation of the main Bearing surface will be affected by deformation of the engine block. The purpose of this paper is to investigate the effect of deformation of the whole engine block on the hydrodynamic lubrication performance of main Bearings.Design/methodology/approach – The loads of main Bearings were calculated by the whole Crankshaft beam‐element finite element method. The lubrication of Crankshaft Bearings was analyzed by dynamic method. The elastic deformations of Bearing surface under oil film pressure were calculated by compliance matrix method. The compliance matrix was established by finit...

  • Lubrication Performance of Crankshaft Bearing for Internal Combustion Engine at Different Working Condition
    Transactions of Csice, 2011
    Co-Authors: Xiao-yong Zhao, Jun Sun, Liping Liu, Bao-ke Huang, Wen-bin Shan, Jian-bo Zhang, Xiao-hui Chai
    Abstract:

    Load and lubrication of Crankshaft Bearing at different working conditions in a four-stroke four-cylinder diesel engine were analyzed.Load of connecting-rod Bearing was calculated by the dynamic cal-culation method,load of all Crankshaft main Bearings were calculated by whole Crankshaft beam-element finite element method,and lubrication of Crankshaft Bearing was analyzed by the dynamic method.Re-sults show that large difference in the changes and numerical value at corresponding moment of load and lubrication performance of Crankshaft Bearing in an engine working cycle at different working condition is presented.The worst lubrication case for Crankshaft Bearing may not occur in engine rated condition.Large difference between the lubrication performance of connecting-rod Bearing and that of main Bearing,and among the lubrication performances of different main Bearings is presented.Thus,it is unreasonable for only analyzing the lubrication performance of certain Crankshaft Bearing in the design of the Crankshaft Bearing.Analysis on lubrication performance of all Crankshaft Bearings at different working conditions is needed.

  • A Dynamic Solution Method for Dynamically Loaded Bearing
    Tribology Transactions, 2011
    Co-Authors: Changlin Gui, Jun Sun
    Abstract:

    The Crankshaft Bearing in an internal combustion engine is a typical dynamically loaded Bearing. In an engine, the Crankshaft and Bearing constitute an inseparable system. When operating, many mechanical actions in this system happen simultaneously and influence each other. This article presents a method to obtain the journal center trajectory that considers the interaction of the Crankshaft and Bearing. The dynamic equations of motion of the Crankshaft and the Reynolds equations were solved simultaneously to determine (calculate) the load on the Bearing, the dynamic response (journal center trajectory), and the tribological performance of the Bearings. The numerical results show that the journal center trajectory of a Crankshaft and tribological performance of Bearings calculated by this method are remarkably different from those obtained by current methods.

Changlin Gui - One of the best experts on this subject based on the ideXlab platform.

  • Systematical Analysis Method for the Mechanical Behaviors of Crankshaft-Bearing System
    Journal of Tribology, 2016
    Co-Authors: Changlin Gui, Jun Sun
    Abstract:

    Various mechanical behaviors will happen at the same time when an engine operates. Based on this concept, in this paper, a systematical analysis method is presented to analyze the multiple mechanical behaviors (tribology, dynamics, stiffness, and strength) of the Crankshaft-Bearing system in an engine. By this method, the analyses of the tribology of Bearing, the dynamics of Crankshaft-Bearing system and the dynamic stress of Crankshaft can be accomplished simultaneously. For example, the effect of the journal misalignment of Crankshaft and the elastic deformation of Bearing bush on the dynamics of Crankshaft-Bearing system, the tribological performances of main Bearings and the dynamic stress of Crankshaft are analyzed emphatically. The results show that the journal misalignment of Crankshaft and the elastic deformation of Bearing bush have remarkable effect on the tribological performances of main Bearings and the dynamic stress of Crankshaft, but have little effect on the dynamics of Crankshaft-Bearing system.

  • A Dynamic Solution Method for Dynamically Loaded Bearing
    Tribology Transactions, 2011
    Co-Authors: Changlin Gui, Jun Sun
    Abstract:

    The Crankshaft Bearing in an internal combustion engine is a typical dynamically loaded Bearing. In an engine, the Crankshaft and Bearing constitute an inseparable system. When operating, many mechanical actions in this system happen simultaneously and influence each other. This article presents a method to obtain the journal center trajectory that considers the interaction of the Crankshaft and Bearing. The dynamic equations of motion of the Crankshaft and the Reynolds equations were solved simultaneously to determine (calculate) the load on the Bearing, the dynamic response (journal center trajectory), and the tribological performance of the Bearings. The numerical results show that the journal center trajectory of a Crankshaft and tribological performance of Bearings calculated by this method are remarkably different from those obtained by current methods.

Gui Chang-lin - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of Elastohydrodynamic Lubrication of Crankshaft Bearing Considering Deformation of Engine Block and Crankshaft
    Transactions of Csice, 2010
    Co-Authors: Gui Chang-lin
    Abstract:

    Analysis of elasto-hydrodynamic lubrication of Crankshaft Bearings considering deformation of whole cylinder block and Crankshaft under load were carried out on the Crankshaft-Bearing system of a fourstroke four-cylinder internal combustion engine.Lubrication of Crankshaft Bearing was analyzed by dynamic method.Deformation of Bearing surface under pressure of oil film was calculated by deformation matrix method.The results show that when deformation of Crankshaft is considered,compared with those without considering deformation of cylinder block,the maximum film pressure is decreased,the minimum film thickness is increased,and the end flow-rate and journal frictional coefficient vary little over engine working cycle when considering deformation of cylinder block.The models of whole cylinder block and single Bearing house were used to calculate deformation of Bearing surface.Results show that engineering calculation accuracy of elasto-hydrodynamic lubrication of Crankshaft Bearings can be met basically by applying the model of simple single Bearing house to calculate the deformation of Bearing surface.

  • Optimization Design of Crankshaft Bearing Combining Crankshaft Strength Factor
    Transactions of Csice, 2009
    Co-Authors: Gui Chang-lin
    Abstract:

    The Crankshaft-Bearing system of a four-stroke four-cylinder engine was taken as the research object,the optimization design of Crankshaft Bearing including the consideration of Crankshaft strength was carried out.The necessity for the inclusion of Crankshaft strength factor in the optimization design of Crankshaft Bearing was studied.The Crankshaft strength was taken as one of restriction conditions when establishing the model of optimization design of Crankshaft Bearing.The particle swarm algorithm was used to optimize the Crankshaft Bearing.The results show that,comparing to the design of Bearing for the original engine,14.21% reduction in total average power loss of Bearing friction is presented by the optimized design of Crankshaft Bearing while meeting the Crankshaft strength.Meanwhile,the optimization design of Crankshaft Bearing without taking into account the effect on Crankshaft was analyzed.In this case,although total average power loss of Bearing friction reduces obviously,the Crankshaft strength can not meet the design demand.Therefore,the reasonable optimization design of Crankshaft Bearing should consider whole Crankshaft-Bearing system and the effect on Crankshaft strength,and optimization solution in system demand can be obtained.

  • Calculation of Dynamic Stress and Fatigue Strength of Crankshaft with Bush Deformation Included
    Journal of Mechanical Engineering, 2009
    Co-Authors: Gui Chang-lin
    Abstract:

    Dynamic stress and fatigue strength of a Crankshaft of diesel engine with four cylinders is studied with consideration of the elastic deformation of bush. Special software ADAMS and ANSYS, assisted by self-designed programs, are adopted to solve the problem. The dynamic pressures of oil film in the Bearings are obtained by analysis of dynamics and tribology of the Crankshaft-Bearing system with consideration of bush deformation. Programming language APDL in ANSYS is adopted to compile program for realizing the force boundary condition, then the dynamic stress on Crankshaft journal surfaces is calculated. The fatigue strength of Crankshaft is calculated by using damage accumulation theory. It is shown that the minimum thickness of oil film decreases and the maximum pressure of oil film increases to a great extent if the elastic deformation of bush is taken into consideration. The dynamic response and stress of Crankshaft vary and the fatigue life of Crankshaft decreases by 15.6%.

  • Elastohydrodynamic Lubrication Analysis of Crankshaft Bearing Considering Crankshaft Deformation under Load and Roughness Surface
    Chinese Journal of Mechanical Engineering, 2009
    Co-Authors: Gui Chang-lin
    Abstract:

    The elastohydrodynamic lubrication properties of Crankshaft Bearings considering Crankshaft deformation under load and surface roughness for a four-cylinder internal combustion engine are studied.The lubrication of Crankshaft Bearing is analyzed by kinetics method.The deformation of bush surface under pressure of oil film is calculated by deformation matrix method.The results show that surface roughness has great effect on Crankshaft Bearing orbit,the surface deformation of Bearing affects Crankshaft Bearing orbit little.When surface roughness of Bearing is considered,the highest film pressure of Crankshaft Bearing increases obviously,the least film thickness decreases remarkably,and the end flow-rate changes little in most time.When elastic deformation of Bearing surface is considered,the highest film pressure of Bearing decreases to different extent;the influence of elastic deformation of Bearing surface on the end flow-rate,journal frictional coefficient and the least film thickness is very small.

J Sun - One of the best experts on this subject based on the ideXlab platform.

  • Multi-objective optimization design of engine Crankshaft Bearing
    Industrial Lubrication and Tribology, 2016
    Co-Authors: J Sun, Xianhao Song, Guangsheng Liu, Enming Miao, Lei Shu, Zheng Zhang, Junwei Zhao
    Abstract:

    Purpose – This paper aims to use the Crankshaft-Bearing system of a four-cylinder internal combustion engine as the studying object, and develop a multi-objective optimization design of the Crankshaft-Bearing. In the current optimization design of engine Crankshaft-Bearing, only the Crankshaft-Bearing was considered as the studying object. However, the corresponding relations of major structure dimensions exist between the Crankshaft and the Crankshaft-Bearing in internal combustion engine, and there are the interaction effects between the Crankshaft and the Crankshaft-Bearing during the operation of internal combustion engine. Design/methodology/approach – The Crankshaft mass and the total frictional power loss of Crankshaft-Bearing s are selected as the objective functions in the optimization design of Crankshaft-Bearing. The Particle Swarm Optimization algorithm based on the idea of decreasing strategy of inertia weight with the exponential type is used in the optimization calculation. Findings – The t...

  • Lubrication Analysis of Crankshaft Bearing Considering Crankshaft Deformation
    SAE Technical Paper Series, 2011
    Co-Authors: J Sun, Xiao-yong Zhao, Hu Wang
    Abstract:

    There is the direct interaction between the Crankshaft and the Crankshaft Bearing in an internal combustion engine. Current lubrication analysis of the Crankshaft Bearing was generally limited in the tribology discipline, only the factors relating to the Bearing were considered, and the journal axis was generally supposed to be parallel to the centerline of Bearing. In reality, the Crankshaft deformation under load will result in the journal misalignment in the Bearing. Although the journal misalignment was considered in a few of the lubrication analyses of Crankshaft Bearings, the causes of journal misalignment were usually thought to be caused by the manufacture, the assembly errors and the deformation of cylinder block. In order to simplify the problem, the journal misalignment was generally assumed to have constant magnitude and direction in an operating cycle of engine. In this paper, a Crankshaft-Bearing system was taken as the research object and the lubrication performance of Crankshaft Bearing considering the Crankshaft deformation under load were analyzed. The Crankshaft deformation and the Bearing load were calculated by the whole Crankshaft beam-element method. The deformation of Bearing under oil film pressure was calculated by the deformation matrix method. The axis orbit of the Crankshaft Bearing was calculated by the dynamic method. The results show that the local axis orbits on the front-end and the rear-end plane of Crankshaft Bearing are changed remarkably when the effect of Crankshaft deformation is considered. The journal misalignment results in the maximum oil film pressure of Bearing be increased obviously, the minimum oil film thickness of Bearing be reduced in the most of time of an engine cycle and the oil film pressure distribution of Bearing be changed, but has only a little effect on the end leakage flow-rate and the frictional coefficient of Bearing. © 2011 SAE International.

  • Whole Crankshaft beam-element finite-element method for calculating Crankshaft deformation and Bearing load of an engine
    Proceedings of the Institution of Mechanical Engineers Part J: Journal of Engineering Tribology, 2009
    Co-Authors: J Sun, J Wang, C Gui
    Abstract:

    AbstractCrankshaft deformation and Bearing load are very important for the lubrication ana-lyses of Crankshaft Bearings of an engine. The calculating methods of Crankshaft deformation and Bearing load will affect the results. There were some problems in the current methods used for calculating Crankshaft deformation and Bearing load, such as complicated model, more time taken for calculation, and error brought by simplification. In this article, the Crankshaft of a four-cylinder engine was taken as the object of study, and the whole Crankshaft beam-element finite-element method to calculate Crankshaft Bearing load and Crankshaft deformation of a multi-cylinder engine was studied. The results show that this method is closer to the actual condition and can calculate the loads of all main Bearings simultaneously compared with traditional methods used for calculating the Crankshaft Bearing load of a multi-cylinder engine. Meanwhile, this method is a simple, convenient, time-saving method used for calculating ...

  • Study on design optimization of a Crankshaft Bearing considering Crankshaft strength for an internal combustion engine
    Proceedings of the Institution of Mechanical Engineers Part J: Journal of Engineering Tribology, 2009
    Co-Authors: J Sun, M Deng, X Cai, C Gui
    Abstract:

    AbstractThe effect on a Crankshaft was not generally considered in the current optimum design of a Crankshaft Bearing for an internal combustion engine, but the corresponding relation between the dimensions of a Crankshaft Bearing and those of a Crankshaft journal exists. In this article, the Crankshaft-Bearing system of a four-stroke, four-cylinder internal combustion engine was taken as the research object, and the optimum design of Crankshaft Bearings considering Crankshaft strength was carried out. The necessity of considering Crankshaft strength in the optimum design of the Crankshaft Bearings was studied. Crankshaft strength was taken as one of the constraints in establishing the model of optimum design of the Crankshaft Bearings. The particle swarm algorithm was used to optimize Crankshaft Bearings. The results show that, compared with the design of Bearings for the original engine, the calculated 14.21 per cent of the total average frictional power loss of the Bearings can be reduced by the optimu...

  • Thermoelastohydrodynamic Lubrication Analysis of Crankshaft Bearing Considering Crankshaft Deformation under Load
    Advanced Tribology, 2009
    Co-Authors: J Sun, Jianglin Liu, C Gui
    Abstract:

    Journal misalignment in Bearing caused by Crankshaft deformation under load exists generally in IC engine. When serious journal misalignment takes place, the minimum oil film thickness of Bearing reduces greatly and the maximum oil film pressure of Bearing increases remarkably. So, it is necessary to consider thermal effects and deformation of Bearing surface when analyzing hydrodynamic lubrication characteristics of misaligned Bearing. In this paper, the thermoelastohydrodymic lubrication properties of Crankshaft Bearings considering Crankshaft deformation under load for a four-cylinder IC engine were analyzed. The lubrication of Crankshaft Bearing was analyzed by kinetics method. The deformation of bush surface under pressure of oil film was calculated by deformation matrix method. The Crankshaft deformation and the load of Crankshaft Bearing were calculated by whole Crankshaft beam-element method. The temperature distributions of journal, Bearing and lubricant were calculated by solving 3-D energy equation and heat conduction equation. The results show that, when Crankshaft deformation is considered, the thermal effects have great influence on the orbit, the maximum oil film pressure and the minimum oil film thickness of Crankshaft Bearing, but the thermal effects affect the end flow-rate and friction coefficient of journal much little.

Sun Jun - One of the best experts on this subject based on the ideXlab platform.

  • Systematical Analysis Method for the Mechanical Behaviors of Crankshaft-Bearing System
    Transactions of Csice, 2010
    Co-Authors: Sun Jun
    Abstract:

    Various mechanical behaviors occur during internal combustion engine operation.A systematical method,named as "binding method",is used to analyze the multi mechanical behaviors of Crankshaft-Bearing system,including dynamics tribology stiffness and strength.Coupling analysis between dynamics and tribology in Crankshaft-Bearing system is conducted to obtain the dynamical oil film pressure of Bearings,and dynamical stress is calculated by dynamically imposing oil film pressure on Crankshaft journal surface.The dynamical response of the system,trobological property of main Bearings and dynamic stress of Crankshaft are studied emphatically considering misalignment of Crankshaft and elastic deformation of Bearing bush.Numerical results show that misalignment of Crankshaft and elastic deformation of Bearing bush have large influence on trobological property of Bearings and dynamic stress of Crankshaft,and small influence on dynamical response of system.

  • Coupling Analysis of Dynamics Tribology and Elastic Mechanics for a Crankshaft Bearing System
    Chinese Internal Combustion Engine Engineering, 2009
    Co-Authors: Sun Jun
    Abstract:

    Multidisciplinary coupling among dynamics,tribology and elastic mechanics(strength and stiffness of Crankshaft) of the Crankshaft-Bearing system of a four cylinder diesel engine was studied by considering the misalignment caused by the elastic deflection of the Crankshaft,ADAMS and ANSYS special software were used to solve the coupling problem.A decoupling idea was presented.The coupling between dynamics and tribology was first solved for the elastic Crankshaft Bearing system and dynamic stress of Crankshaft journal surfaces was then calculated by using ANSYS.A special program was designed by the APDL(ANSYS parameter design language).The results show that the minimum thickness of oil film decreases and the maximum pressure of oil film increases as the Crankshaft misalignment is taken into account,the dynamic response and stress of the Crankshaft also vary and fatigue safety coefficient decreases by 23.24%.

  • Study on Fatigue Strength of Crankshaft-Bearing System of Engine Crankshaft based on Dynamic and Tribological Analysis
    Transactions of Csice, 2008
    Co-Authors: Sun Jun
    Abstract:

    A novel method to calculate the dynamic stress on the surface of a Crankshaft based on the dynamic and tribological behavior of the Crankshaft-Bearing system is presented for a four cylinder internal combustion engine.In the finite element analysis,by exerting the dynamic pressures of oil film on the surface of the Crankshaft,the dynamic stress on the surface of Crankshaft journal is calculated.The accumulative damage theory is applied in the calculation of the Crankshaft fatigue strength.Numerical results show that the dynamic stress distribution on the Crankshaft journals is mainly determined by bending,torsion and stress concentration of the Crankshaft as oil film loads are applied.The dynamic stress variation with time is closely related to the firing sequence of engine.The safety coefficient of Crankshaft decreases by 5.34% by the accumulative damage theory compared with the traditional method.

  • Optimization Design of Crankshaft Bearing of Internal Combustion Engine Based on Particle Swarm Algorithm
    Internal combustion Engines, 2008
    Co-Authors: Sun Jun
    Abstract:

    In this paper, based on the database of Bearing performances established by lubrication analysis of Crankshaft Bearing, the lubrication performances of Bearing with different parameters were gotten by interpolation. Then, Crankshaft Bearing was optimized to get minimum friction power loss by using particle swarm algorithm. Crankshaft Bearings of N485 diesel were taken for an example of optimization. The result shows that above method is practical and rational.

  • Coupling Analysis on Behavior of Dynamics and Tribology for Crankshaft-Bearing System
    Vehicle Engine, 2007
    Co-Authors: Sun Jun
    Abstract:

    Based on multi-flexible body dynamic theory,the dynamics simulation model of Crankshaft-Bearing system for a 4-cylinder diesel engine was built with ADAMS software considering the tribology performance of main Bearing,and the dynamics response of Crankshaft and the reacting forces of main Bearings were also acquired by simulation.Then the dynamic variation laws of the maximum oil film pressure and the minimum oil film thickness for each main Bearing were acquired by lubrication analysis of main Bearing with the finite difference method.The result shows that the radial vibration response for each main journal of Crankshaft,the reacting forces of each main Bearing,the maximum oil film pressure and the minimum oil film thickness have symmetrical structure.