轴向往复运动下微槽轴承混合润滑数值模型
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摘要
建立了考虑轴向往复运动以及轴颈偏斜的人字槽滑动轴承混合润滑(Mixed-EHL)数值模型。通过瞬态平均雷诺方程求解了考虑表面粗糙度效应的油膜压力,通过影响系数法求得轴瓦内表面弹性变形,而界面接触压力则由Lee-Ren粗糙峰接触模型求得。通过数值模拟得到了承载力、接触载荷比、摩擦因数等参数随时间的变化规律,并研究了往复运动间距及偏斜角对混合润滑性能的影响。研究表明:油膜力与轴向速度呈同相变化,接触载荷与轴向速度呈反相变化;随运动间距的增大,滑动轴承在反向运动历程中的承载能力和润滑性能显著降低;偏斜角增大会降低轴承的混合润滑性能以及承载能力。
A numerical model was developed to investigate the mixed lubrication performance of herringbone grooved journal bearing when axial reciprocating motion and journal misalignment were considered. The oil film pressure considering the roughness effect can be obtained by transient average Reynolds equation. The elastic deformation can be obtained through influence function method, and the contact pressure can be simulated by Lee-Ren asperity contact model. The variation of oil-film force,contact load ratio, and friction coefficient with time were investigated by numerical simulation, and the effect of axial movement amplitude and misalignment angle on mixed lubrication performance were also studied. The research suggests that the oil-film force is corresponding over axial velocity, and the contact pressure shows inverse variation with axial velocity. Besides, the increase of axial movement amplitude in negative movement state will result in a significant reduction in load capacity and lubrication performance of journal bearing. The research also shows that the load capacity and lubrication performance of journal bearing decrease with the increase in misalignment angle.
A numerical model was developed to investigate the mixed lubrication performance of herringbone grooved journal bearing when axial reciprocating motion and journal misalignment were considered. The oil film pressure considering the roughness effect can be obtained by transient average Reynolds equation. The elastic deformation can be obtained through influence function method, and the contact pressure can be simulated by Lee-Ren asperity contact model. The variation of oil-film force,contact load ratio, and friction coefficient with time were investigated by numerical simulation, and the effect of axial movement amplitude and misalignment angle on mixed lubrication performance were also studied. The research suggests that the oil-film force is corresponding over axial velocity, and the contact pressure shows inverse variation with axial velocity. Besides, the increase of axial movement amplitude in negative movement state will result in a significant reduction in load capacity and lubrication performance of journal bearing. The research also shows that the load capacity and lubrication performance of journal bearing decrease with the increase in misalignment angle.
引文
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[3]Wang Y,Wang Q J,Lin C.A mixed-EHL analysis of effects of misalignments and elastic deformations on the performance of a coupled journal-thrust bearing system[J].Tribology International,2006,39(4):281-289.
[4]Sharma S C,Phalle V M,Jain S C.Combined influence of wear and misalignment of journal on the performance analysis of three-lobe three-pocket hybrid journal bearing compensated with capillary restrictor[J].Journal of Tribology,2012,134(1):011703.
[5]Rao T,Sawicki J T.Stability characteristics of herringbone grooved journal bearings incorporating cavitation effects[J].Journal of Tribology,2004,126(2):281-287.
[6]Lanes R F,Flack R D.Effects of three-lobe bearing geometries on flexible rotor stability[J].ASLE Transactions,1982,25(3):377-385.
[7]Usman A,Park C W.Numerical investigation of tribological performance in mixed lubrication of textured piston ring-liner conjunction with a non-circular cylinder bore[J].Tribology International,2017,105:148-157.
[8]Tang He-sheng,Ren Yan,Xiang Jia-wei.A novel model for predicting thermoelastohydrodynamic lubrication characteristics of slipper pair in axial piston pump[J].International Journal of Mechanical Sciences,2017,124/125:109-121.
[9]Ma X,Wang Q J,Lu X,et al.A transient hydrodynamic lubrication model for piston/cylinder interface of variable length[J].Tribology International,2018,118:227-239.
[10]Patir N,Cheng H S.Effect of surface roughness orientation on the central film thickness in EHD contacts[C]∥Proceedings of the Fifth Leeds-Lyon Symposium on Tribology,Bury St.Edmunds,UK,1979:15-21.
[11]Shi F H,Wang Q.A mixed-TEHD model for journalbearing conformal contacts-part I:model formulation and approximation of heat transfer considering asperity contact[J].JournalofTribology,1998,120(2):198-205.
[12]Lee S C,Ren N.Behavior of elastic-plastic rough surface contacts as affected by surface topography,load,and material hardness[J].Tribology Transactions,1996,39(1):67-74.
[13]Wang Y,Zhang C,Wang Q J,et al.A mixed-TE-HD analysis and experiment of journal bearings under severe operating conditions[J].Tribology International,2002,35(6):395-407.
[14]Hirs G G.The load capacity and stability characteristics of hydrodynamic grooved journal bearings[J].Tribology Transactions,1965,8(3):296-305.
[15]Wang Q,Shi F H,Lee S C.A mixed-TEHD model for journal-bearing conformal contact-part II:contact,film thickness,and performance analyses[J].Journal of Tribology,1998,120(2):206-213.
[2]Qiu Z L,Tieu A K.Misalignment effect on the static and dynamic characteristics of hydrodynamic journal bearings[J].JournalofTribology,1995,117(4):717-723.
[3]Wang Y,Wang Q J,Lin C.A mixed-EHL analysis of effects of misalignments and elastic deformations on the performance of a coupled journal-thrust bearing system[J].Tribology International,2006,39(4):281-289.
[4]Sharma S C,Phalle V M,Jain S C.Combined influence of wear and misalignment of journal on the performance analysis of three-lobe three-pocket hybrid journal bearing compensated with capillary restrictor[J].Journal of Tribology,2012,134(1):011703.
[5]Rao T,Sawicki J T.Stability characteristics of herringbone grooved journal bearings incorporating cavitation effects[J].Journal of Tribology,2004,126(2):281-287.
[6]Lanes R F,Flack R D.Effects of three-lobe bearing geometries on flexible rotor stability[J].ASLE Transactions,1982,25(3):377-385.
[7]Usman A,Park C W.Numerical investigation of tribological performance in mixed lubrication of textured piston ring-liner conjunction with a non-circular cylinder bore[J].Tribology International,2017,105:148-157.
[8]Tang He-sheng,Ren Yan,Xiang Jia-wei.A novel model for predicting thermoelastohydrodynamic lubrication characteristics of slipper pair in axial piston pump[J].International Journal of Mechanical Sciences,2017,124/125:109-121.
[9]Ma X,Wang Q J,Lu X,et al.A transient hydrodynamic lubrication model for piston/cylinder interface of variable length[J].Tribology International,2018,118:227-239.
[10]Patir N,Cheng H S.Effect of surface roughness orientation on the central film thickness in EHD contacts[C]∥Proceedings of the Fifth Leeds-Lyon Symposium on Tribology,Bury St.Edmunds,UK,1979:15-21.
[11]Shi F H,Wang Q.A mixed-TEHD model for journalbearing conformal contacts-part I:model formulation and approximation of heat transfer considering asperity contact[J].JournalofTribology,1998,120(2):198-205.
[12]Lee S C,Ren N.Behavior of elastic-plastic rough surface contacts as affected by surface topography,load,and material hardness[J].Tribology Transactions,1996,39(1):67-74.
[13]Wang Y,Zhang C,Wang Q J,et al.A mixed-TE-HD analysis and experiment of journal bearings under severe operating conditions[J].Tribology International,2002,35(6):395-407.
[14]Hirs G G.The load capacity and stability characteristics of hydrodynamic grooved journal bearings[J].Tribology Transactions,1965,8(3):296-305.
[15]Wang Q,Shi F H,Lee S C.A mixed-TEHD model for journal-bearing conformal contact-part II:contact,film thickness,and performance analyses[J].Journal of Tribology,1998,120(2):206-213.