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Science China(Technological Sciences) 2024年第3期67卷 853-862页

作者： HONG Tao XING GuanYing ZUO HuaiYu XUE Song LUO XiaoBing State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.

关键词： journal bearing herringbone groove hydrodynamic effect micro-pump

Misalignment analysis of journal bearing influenced by asymmetric deflection,based on a simple stepped shaft model

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第9期13卷 647-664页

作者： Zhen-peng HE Jun-hong ZHANG Wei-song XIE Zhou-yu LI Gui-chang ZHANG State Key Laboratory of Engine Tianjin UniversityTianjin 300072China Deparment of Mathematics School of ScienceTianjin University Tianjin 300072Ckina

The effects of journal misalignment on a journal bearing caused by an asymmetric rotor structure are presented in this study.A new model considering the asymmetric deflection is ***,the thermo-hydrodynamic of the oil film in the journal bearing and straightforward elasticity theory are considered in the *** on the structure stiffness equivalent characteristic,a simple stepped shaft can reflect the entire complex structure *** existing lubrication model,which does not consider this angle component,is not very precise for journal *** pressure,misalignment angle,velocity field,oil leakage,and temperature field were calculated and compared in the journal bearing *** results indicate that bearing performances are greatly affected by misalignment caused by the asymmetric structure.A simple stepped shaft can effectively represent a misaligned journal bearing in a rotor-bearing system.

关键词： Misalignment Stepped shaft Asymmetric structure journal bearing

Numerical study on the influences of preload factor on the properties of three-lobe journal bearing

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journal of Harbin Institute of Technology(New Series) 2008年第1期15卷 33-38页

作者：阎庆华颜勇明安琦 School of Mechanical and Power Engineering East China University of Science and Technology

The influences of preload factor on the characteristics of three-lobe journal bearing, such as dimensionless load capacity, attitude angle, stiffness coefficients and damping coefficients, were studied by using the numerical calculation. And the influences of eccentricity ratio and wide-to-diameter ratio on the characteristics of journal bearing were investigated as well. The results show that with the increasing of preload factor, eccentricity ratio and wide-to-diameter ratio, the dimensionless load capacity and damping coefficients increase; meanwhile, the absolute value of stiffness coefficients increases; and with the increasing of preload factor and eccentricity ratio and the decreasing of wide-to-diameter ratio, the attitude angle decreases. The study offers theoretical base for engineering application of three-lobe journal bearing.

关键词： journal bearing structure parameter preload factor static and dynamic characteristics numerical study

THERMOHYDRODYNAMIC LUBRICATION ANALYSIS ON EQUILIBRIUM POSITION AND DYNAMIC COEFFICIENT OF journal bearing

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Transactions of Nanjing University of Aeronautics and Astronautics 2012年第3期29卷 227-236页

作者：李元生于明敖良波岳珠峰西北工业大学工程力学系

The finite element method （FEM） is introduced to calculate the oil film pressure and temperature distribution of a journal bearing. The perturbation is performed directly on the finite element equation. Consequently, the Jacobian matrices of the oil film forces are concisely obtained. The equilibrium position of the bearing with a given static load is found by the Newton-Raphson method. As byproducts, dynamic coefficients are obtained simultaneously without any extra computing time. From the numerical results, it is concluded that the effects of film temperature on stiffness coefficients are bigger than those on damping coefficients. With the increase of rotational speed, the load capacity and the stiffness coefficients of the journal bearing are increased when the eccentricity is small, while decreased when the eccentricity is big.

关键词： thermohydrodynamic lubrication thermal effect finite element analysis journal bearing

Spherical contact mechanical analysis of roller cone drill bits journal bearing

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Petroleum 2016年第2期2卷 208-214页

作者： Wei He Yang Chen Junchao He Weiling Xiong Tong Tang Hao OuYang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China Sichuan Special Equipment Inspection Institute Chengdu 610061China

Fang contact model is introduced to analyze stress of the spherical fixed ring journal *** calculation programs in the MATLAB software which are utilized to calculate the contact characteristics of roller cone drill bits spherical fixed ring journal *** addition,effects of external load,radius clearance values,and material parameter on the mechanics performance were *** results show that the value of external load has a direct pronounced effect on the contact characteristics of journal *** is a significant positive correlation between contact pressure and external load,radius clearance value,and the Young's modulus of ***,there is an evident negative correlation between contact radius of journal bearing and radius clearance value,and the Young's modulus of *** smaller radius clearance value of journal bearing is,the more centralized contact region will be,so the corresponding contact pressure will be *** the perspective of reducing friction and wear,we need select the materials which have high strength and good *** only might this can improve the wear resistance,it also effectively decreases the contact *** this case,we can prolong the service life of roller cone drill bits journal bearing.

关键词： Roller cone drill bits journal bearing Spherical fixed ring Contact characteristics

STUDY ON PERFORMANCE OF COMPOSITE journal bearing SEALED AND LUBRICATED WITH FERROFLUID

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Chinese journal of Mechanical Engineering 1998年第3期11卷 2-7页

作者： Zhang Song Kong Xianmei Chen Darong National Tribology Laboratory,Qinghua University Yu Lie Zhu Jun Xi’an Jiaotong University

The theoretical computation model of the composite journal bearing sealed and lubricated with ferrofluid is established The oil film pressure distribution,temperature field and heat conduction equation of the bearing liner are jointly calculated The static and dynamic properties of the bearing under condition of different eccentricities and ratios of width to diameter are obtained and discussed The results show the feasibility of this type of bearing for smaller eccentricities and width to diameter ratios,and that the oil film temperature,which is more subject to be influenced by the rotating speed,is higher than that of the bearing with leakage flow The key problem of the further development and application of the bearing is to design more reasonable and effective types of seal structures

关键词： Ferrofluid journal bearing Self seal

AN EXPERIMENTAL STUDY ON THE INFLUENCES OF WATERY OIL ON THE STATIC CHARACTERISTIC OF journal bearing

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AN EXPERIMENTAL STUDY ON THE INFLUENCES OF WATERY OIL ON THE...

Thermoelastohydrodynamic Behavior of a journal bearing with Turbulent Flow

第三届摩擦疲劳学国际会议

作者： Ah Qi Mechanical Engineering Department East China University of Science and Technology Shanghai 200237 China

＜正＞In practice when journal bearing working the lubricating oil in it usually infiltrated with water drops because of system leaking, oil film pressure changing, conucting the vapour of the ambient and other unknown reason, which make the journal bearing usually lubricated with watery oil. The lubricating behaviour of water is much different from oil, so the lubricating property of oil will change when water drops were entrained in oil. Up to now no people have taken detailed research on such project. In this paper a new experimental device for journal bearing lubricated with watery oil was developed by remaking the journal bearing testing machine MPV-1500. By use of this device, the influences of watery oil on journal bearing friction force, oil film pressure and load capacity were investigated experimentally in detail, and found that the watery oil will decrease the friction force and oil film pressure of journal bearing to some extent and the influence on the load of journal bearing is comparatively complex, in some condition make it increase and some condition make it decrease.

关键词： Watery oil journal bearing Friction force Oil film pressure Load capacity

来源： cnki会议评论

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journal of Mechanics Engineering and Automation 2019年第7期9卷 230-235页

作者： Aziz Ouadoud Otman Benmahjoub Department of Physics Faculty PolydisciplinaryUniversity of Abdelmaleek EssaadiLarache 92004Morocco

Turbulence is an irregular fluid motion in which the various flow properties such as velocity and pressure show random variations with time and position.A number of authors proposed different solutions *** pressure distribution,temperature prediction and Thermo-Hydrodynamic(THD)*** a fluid film bearing,the pressure in the oil film satisfies the Reynolds equation with a variation in the thickness of the lubricating *** the presented cases of fluid-structure interaction analyses,all important phenomena accompanying bearing operation are considered,*** flow,structure movements and their deformations as well as heat transfer in case of thrust *** this paper,the authors have developed an empirical relationship to determine the effect of lubrication when considering thermoelastohydrodynamic(TEHD)lubrication with turbulent *** critical point of this work is to import the matrix data(the pressure and temperature fields...)from the fluid domain to the internal surface of the bearing with a precision of the mesh especially in the contact *** results are presented in the median plane as a function of the bearing angle.A parametric study deals with the influence of rotation speed and the type of turbulence model on the pressure,temperature,deformation and stress intensity fields.

关键词： TEHD journal bearing computational fluid dynamics(CFD)

Application of Computational Fluid Dynamics and Fluid Structure Interaction Techniques for Calculating the 3D Transient Flow of journal bearings Coupled with Rotor Systems

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Chinese journal of Mechanical Engineering 2012年第5期25卷 926-932页

作者： LI Qiang YU Guichang LIU Shulian ZHENG Shuiying Institute of Chemical Machinery Zhejiang University Hangzhou 310027 China Department of Electro-mechanical Engineering Zhejiang University of Science & Technology Hangzhou 310023 China

journal bearings are important parts to keep the high dynamic performance of rotor machinery. Some methods have already been proposed to analysis the flow field of journal bearings, and in most of these methods simplified physical model and classic Reynolds equation are always applied. While the application of the general computational fluid dynamics （CFD）-fluid structure interaction （FSI） techniques is more beneficial for analysis of the fluid field in a journal bearing when more detailed solutions are needed. This paper deals with the quasi-coupling calculation of transient fluid dynamics of oil film in journal bearings and rotor dynamics with CFD-FSI techniques. The fluid dynamics of oil film is calculated by applying the so-called ＂dynamic mesh＂ technique. A new mesh movement approacb is presented while the dynamic mesh models provided by FLUENT are not suitable for the transient oil flow in journal bearings. The proposed mesh movement approach is based on the structured mesh. When the joumal moves, the movement distance of every grid in the flow field of bearing can be calculated, and then the update of the volume mesh can be handled automatically by user defined function （UDF）. The journal displacement at each time step is obtained by solving the moving equations of the rotor-bearing system under the known oil film force condition. A case study is carried out to calculate the locus of the journal center and pressure distribution of the journal in order to prove the feasibility of this method. The calculating results indicate that the proposed method can predict the transient flow field of a journal bearing in a rotor-bearing system where more realistic models are involved. The presented calculation method provides a basis for studying the nonlinear dynamic behavior of a general rotor-bearing system.

关键词： mesh movement transient flow computational fluid dynamics (CFD) fluid-structure interaction (FSI) journal bearing

STUDY ON THE INFLUENCES OF BUBBLY OIL ON THE CAVITATION EROSION IN journal bearingS OF ENGINES

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Chinese journal of Mechanical Engineering 2001年第4期14卷 378-380,384页

作者： An Qi (Mechanical Engineering Department,East China University of Science and Technology) Priest M, Taylor C M (The University of Leeds,LS2 9JT,UK) 华东理工大学上海 The University of Leeds 英国

A simulating experimental device for journal bearings of engines is established by use of the mechanism of ultrasonic vibration This device can make the pressure inside the oil film changed at ultrasonic frequency,which enable the specimen surface to be damaged by cavitation erosion in a comparatively short time Connecting with the bubbly oil producing device,this rig can investigate the influence of bubbly oil on the cavitation erosion Through detailed experimental research it is found that the bubbly oil decreases the cavitation erosion in journal bearings of engines This result is analyzed reasonably from mechanism of cavitation erosion.

关键词： Cavitation erosion Bubbly oil journal bearing Engine