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A smoothed assumed enhanced strain method for frictional contact with constant strain elements
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作者 Fushen Liu Wei Sun +1 位作者 Minghui Li Xiaonan Shang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4369-4385,共17页
This paper presents a finite element framework for imposing frictional contact conditions on embedded fracture faces,implemented by the constant-strain assumed enhanced strain(AES)method,where penalty method is used t... This paper presents a finite element framework for imposing frictional contact conditions on embedded fracture faces,implemented by the constant-strain assumed enhanced strain(AES)method,where penalty method is used to impose both non-penetration constraint and Coulomb’s law of friction.The proposed constant-strain AES method for modeling embedded frictional contact can be cast into an integration algorithm similar to those used in the classical plasticity theory,where displacement jump is calculated from the local traction equilibrium at Gauss point,so the method does not introduce any additional global degrees of freedom.Moreover,constant-strain elements are often desirable in practice because they can be easily created automatically for large-scale engineering applications with complicated geometries.As encountered in other enriched finite element methods for frictional contact,the problem of normal contact pressure oscillations is also observed in the constant-strain AES method.Therefore,we developed a strain-smoothing procedure to effectively mitigate the oscillations.We investigated and verified the proposed AES framework through several numerical examples,and illustrated the capability of this method in solving challenging nonlinear frictional contact problems. 展开更多
关键词 Assumed enhanced strain(AES)method frictional contact Strain-smoothing method Penalty method
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Existence and numerical approximation of a solution to frictional contact problem for electro-elastic materials
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作者 Othman Baiz EL-Hassan Benkhira Rachid Fakhar 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期201-219,共19页
In this paper,a frictional contact problem between an electro-elastic body and an electrically conductive foundation is studied.The contact is modeled by normal compliance with finite penetration and a version of Coul... In this paper,a frictional contact problem between an electro-elastic body and an electrically conductive foundation is studied.The contact is modeled by normal compliance with finite penetration and a version of Coulomb’s law of dry friction in which the coefficient of friction depends on the slip.In addition,the effects of the electrical conductivity of the foundation are taken into account.This model leads to a coupled system of the quasi-variational inequality of the elliptic type for the displacement and the nonlinear variational equation for the electric potential.The existence of a weak solution is proved by using an abstract result for elliptic variational inequalities and a fixed point argument.Then,a finite element approximation of the problem is presented.Under some regularity conditions,an optimal order error estimate of the approximate solution is derived.Finally,a successive iteration technique is used to solve the problem numerically and a convergence result is established. 展开更多
关键词 piezoelectric material frictional contact variational Inequality fixed point process finite element method error estimation iteration method
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Contact Problem in Decagonal Two-Dimensional Quasicrystal 被引量:6
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作者 周旺民 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期51-55,共5页
As a new structure of solid matter quasicrystal brings profound new ideas to the traditional condensed matter physics, its elastic equations are more complicated than that of traditional crystal. A contact problem of ... As a new structure of solid matter quasicrystal brings profound new ideas to the traditional condensed matter physics, its elastic equations are more complicated than that of traditional crystal. A contact problem of decagonal two? dimensional quasicrystal material under the action of a rigid flat die is solved satisfactorily by introducing displacement function and using Fourier analysis and dual integral equations theory, and the analytical expressions of stress and displacement fields of the contact problem are achieved. The results show that if the contact displacement is a constant in the contact zone, the vertical contact stress has order -1/2 singularity on the edge of contact zone, which provides the important mechanics parameter for contact deformation of the quasicrystal. 展开更多
关键词 decagonal two-dimensional quasicrystal contact problem stress and displacement
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FRICTIONAL CONTACT MULTIPOLE-BEM AND 3-D ANALYSIS OF SCREWPAIRS 被引量:4
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作者 ChenXiumin ShenGuangxian LiuDeyi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第3期411-414,共4页
The 3-D traction field in the pressure screw-pair of a 3 500 heavy and mediumplate mill press down system is successfully calculated by applying the 3-D frictional contactmultipole-BEM and the corresponding program th... The 3-D traction field in the pressure screw-pair of a 3 500 heavy and mediumplate mill press down system is successfully calculated by applying the 3-D frictional contactmultipole-BEM and the corresponding program that has been developed. The computing results show themedium diameter orientation is unreliable, especially under the interference of an outer forcecouple. Under such working conditions, the circumferential traction distribution on the screw teethis extremely uneven, which is the main reason for the destruction and short life time ofscrew-pairs. When utilizing the same precision (the relative tolerance is 10X10^(-5)), themultipole-BEM uses almost the same CPU time as used by the FEM, but the needed computer memory sizeis only one eightieth of that needed by the FEM (10 MB vs. 800 MB). The multipole-BEM is well suitedfor computing large-scale engineering problems. 展开更多
关键词 Multipole-BEM Point-to-surface contact with friction MathematicalProgramming Heavy and medium plate mill Pressure screwpair
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Numerical Analysis of Rolling-sliding Contact with the Frictional Heat in Rail 被引量:3
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作者 LI Wei WEN Zefeng +1 位作者 JIN Xuesong WU Lei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第1期41-49,共9页
Thermal damage caused by frictional heat of rolling-sliding contact is one of the most important failure forms of wheel and rail. Many studies of wheel-rail frictional heating have been devoted to the temperature fiel... Thermal damage caused by frictional heat of rolling-sliding contact is one of the most important failure forms of wheel and rail. Many studies of wheel-rail frictional heating have been devoted to the temperature field, but few literatures focus on wheel-rail thermal stress caused by frictional heating. However, the wheel-rail creepage is one of important influencing factors of the thermal stress In this paper, a thermo-mechanical coupling model of wheel-rail rolling-sliding contact is developed using thermo-elasto-plastic finite element method. The effect of the wheel-rail elastic creepage on the distribution of heat flux is investigated using the numerical model in which the temperature-dependent material properties are taken into consideration. The moving wheel-rail contact force and the frictional heating are used to simulate the wheel rolling on the rail. The effect of the creepage on the temperature rise, thermal strain, residual stress and residual strain under wheel-rail sliding-rolling contact are investigated. The investigation results show that the thermally affected zone exists mainly in a very thin layer of material near the rail contact surface during the rolling-sliding contact. Both the temperature and thermal strain of rail increase with increasing creepage. The residual stresses induced by the frictional heat in the surface layer of rail appear to be tensile. When the creepage is large, the frictional heat has a significant influence on the residual stresses and residual strains of rail. This paper develops a thermo-meehanical coupling model of wheel-rail rolling-sliding contact, and the obtained results can help to understand the mechanism of wheel/rail frictional thermal fatigue. 展开更多
关键词 wheel-rail rolling-sliding contact frictional heating CREEPAGE residual stress/strain thermo-elasto-plastic finite element method
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Frictional contact algorithm study on the numerical simulation of large deformations in deep soft rock tunnels 被引量:5
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作者 GUO Hongyun CHEN Xin +2 位作者 HE Manchao XI Shouzhong TANG Juzhen 《Mining Science and Technology》 EI CAS 2010年第4期524-529,共6页
There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method... There exist three types of nonlinear problems in large deformation processes of deep softrock engineering, i.e., nonlin- earity caused by material, geometrical and contact boundary. In this paper, the numerical method to tackle the nonlinear eontact and large deformation problem in A Software on Large Deformation Analysis for Soft Rock Engineering at Great Depth was presented. In the software, based on Lagrange multiplier method and Coulomb friction law, kinematic constraints on contact boundaries were introduced in functional function, and the finite element equations was established for two incremental large deformation analyses models, polar decomposition model and additive decomposition model. For every incremental loading step, by searching for the contact points in the potential contact interfaces (the excavation boundaries), the Lagrange multipliers, i.e., contact forces are cal- culated iteratively by Gauss-Seidel method, and justified through satisfy the inequalities of static constraint on contact boundaries. With the software, large deformation and frictional contact of a transport roadway were analyzed numerically by the two models. The numerical examples demonstrated the efficiency of the method used in the software. 展开更多
关键词 deep softrock engineering large deformation frictional contact Lagrange multiplier method FEM
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Numerical method for dynamics of multi-body systems with two-dimensional Coulomb dry friction and nonholonomic constraints 被引量:3
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作者 Ziyao XU Qi WANG Qingyun WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第12期1733-1752,共20页
Based on the dynamical theory of multi-body systems with nonholonomic constraints and an algorithm for complementarity problems, a numerical method for the multi-body systems with two-dimensional Coulomb dry friction ... Based on the dynamical theory of multi-body systems with nonholonomic constraints and an algorithm for complementarity problems, a numerical method for the multi-body systems with two-dimensional Coulomb dry friction and nonholonomic constraints is presented. In particular, a wheeled multi-body system is considered. Here, the state transition of stick-slip between wheel and ground is transformed into a nonlinear complementarity problem (NCP). An iterative algorithm for solving the NCP is then presented using an event-driven method. Dynamical equations of the multi-body system with holonomic and nonholonomic constraints are given using Routh equations and a con- straint stabilization method. Finally, an example is used to test the proposed numerical method. The results show some dynamical behaviors of the wheeled multi-body system and its constraint stabilization effects. 展开更多
关键词 non-smooth dynamics nonholonomic constraint Coulomb dry friction two-dimensional friction nonlinear complementarity problem (NCP)
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NON-INTERIOR SMOOTHING ALGORITHM FOR FRICTIONAL CONTACT PROBLEMS 被引量:1
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作者 张洪武 何素艳 李兴斯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第1期47-58,共12页
A new algorithm for solving the three-dimensional elastic contact problem with friction is presented. The algorithm is a non-interior smoothing algorithm based on an NCP-function. The parametric variational principle ... A new algorithm for solving the three-dimensional elastic contact problem with friction is presented. The algorithm is a non-interior smoothing algorithm based on an NCP-function. The parametric variational principle and parametric quadratic programming method were applied to the analysis of three-dimensional frictional contact problem. The solution of the contact problem was finally reduced to a linear complementarity problem, which was reformulated as a system of nonsmooth equations via an NCP-function. A smoothing approximation to the nonsmooth equations was given by the aggregate function. A Newton method was used to solve the resulting smoothing nonlinear equations. The algorithm presented is easy to understand and implement. The reliability and efficiency of this algorithm are demonstrated both by the numerical experiments of LCP in mathematical way and the examples of contact problems in mechanics. 展开更多
关键词 three-dimensional frictional contact problem parametic quadratic programming method linear complementarity problem NCP-function aggregate function non-interior smoothing algorithm
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Effects of Inter-Particle Frictional Coefficients on Evolution of Contact Networks in Landslide Process 被引量:2
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作者 Lian Jiang Enlong Liu +1 位作者 Jianqiu Tian Xiaoqiong Jiang 《Engineering(科研)》 2017年第11期917-936,共20页
During the process of landslide, its dynamic mechanism is important to understand and predict these kinds of natural hazard. In this paper, a new method, based on concepts of complex networks, has been proposed to inv... During the process of landslide, its dynamic mechanism is important to understand and predict these kinds of natural hazard. In this paper, a new method, based on concepts of complex networks, has been proposed to investigate the evolution of contact networks in mesoscale during the sliding process of slope. A slope model was established using the discrete element method (DEM), and influences of inter-particle frictional coefficients with four different values on?dynamic landslides were studied. Both macroscopic analysis on slope?landslide?and mesoanalysis on structure evolution of contact networks, including the?average degree, clustering coefficient?and N-cycle, were done during the process?of landslide. The analysis results demonstrate that: 1) with increasing inter-particle?frictional coefficients, the displacement of slope decreases and the stable angle of slope post-failure increases, which is smaller than the peak internal frictional angle;2) the average degree decreases with the increase of inter-particle frictional coefficient. When the displacement at the toe of the slope is smaller,?the average degree there changes more greatly with increasing inter-particle?frictional coefficient;3) during the initial stage of landslide, the clustering coefficient?reduces sharply, which may leads to easily slide of slope. As the landslide?going?on, however, the clustering coefficient?increases denoting increasing stability?with?increasing inter-particle frictional coefficients. When the inter-particle?frictional coefficient is smaller than 0.3, its variation can affect the clustering coefficient?and stable inclination of slope post-failure greatly;and 4) the number of?3-cycle increases, but 4-cycle and 5-cycle decrease with increasing inter-particle frictional coefficients. 展开更多
关键词 EVOLUTION of contact NETWORK LANDSLIDE Complex NETWORK Inter-Particle frictional Clustering COEFFICIENT N-Cycle
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A new visco-elastic contact model of traveling wave ultrasonic motor with stator frictional layer 被引量:1
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作者 孙凤艳 曲建俊 吴培莲 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第5期705-710,共6页
A new contact model of traveling wave ultrasonic motor (TWUSM) with a visco-elastic stator frictional layer was presented. In this model, the initial boundaries were revised, and the rotor revolution speed could he ... A new contact model of traveling wave ultrasonic motor (TWUSM) with a visco-elastic stator frictional layer was presented. In this model, the initial boundaries were revised, and the rotor revolution speed could he calculated iteratively. This model was compared with compliant slider and rigid stator model. The results of motor characteristics simulations showed that the motors based on this model would gain bigger stall torque. Then the friction and wear characteristics of two models were analyzed. The motors based on this model had lower coefficient of friction and better wear resistance. 展开更多
关键词 ultrasonic motor contact model frictional material
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Interfacial friction effects on sealing performances of elastomer packer
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作者 Peng-Cheng Wang Ming-Hui Chen +2 位作者 Jim Jenkinson Yong-Xin Song Li Sun 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期2037-2047,共11页
Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic fracking.In practice sealing performances of such plugs ar... Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic fracking.In practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and casing.In previous studies,the impact of friction forces on sealing performance is often overlooked.This work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing performances.We first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac plug.Then we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after setting.With the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug products.In addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial stress.This study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces. 展开更多
关键词 Elastomer seal friction Sealing performance contact stress
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BOUNDARY ELEMENT-COMPLIANCE MATRIX METHOD FOR 3D ELASTIC FRICTIONAL CONTACT ANALYSIS
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作者 BAO Jin-song +6 位作者 (鲍劲松) ZHANG Wei-hua (张伟华) GONG Yun-peng (巩云鹏) 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期59-63,共5页
Boundary element compliance matrix (BEM) method to deal with 3D elastic frictional contact problem was presented, and its calculation method and convergence criteria were discussed. It has the advantages of both bound... Boundary element compliance matrix (BEM) method to deal with 3D elastic frictional contact problem was presented, and its calculation method and convergence criteria were discussed. It has the advantages of both boundary element method and compliance matrix methods: small number of inputting data, simple and convenient model, precise solution, short calculating time and requirements for a small quantity of computer memory. In comparison to the other BEM with friction problems, we obtain more precise solution and less iteration times. The effect of friction coefficient on contact area. contace state, and relative displacement, normal and tangential stress was analyzed by two examples. And because of the quickness of calculation of program and efficient method, we visualize the result in virtual reality (VR) environment. We grant the real time of VR and provide more immersion to users who ware the VR device. 展开更多
关键词 frictional contact analysis BEM COMPLIANCE MATRIX method VR
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Propagation of harmonic waves through micro gap with consideration of frictional contact
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作者 陈小云 于桂兰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第11期1423-1436,共14页
Transmission of elastic waves through a micro gap between two solids with consideration of frictional contact is investigated. By using the Fourier analysis technique and the corrective solution method, the nonlinear ... Transmission of elastic waves through a micro gap between two solids with consideration of frictional contact is investigated. By using the Fourier analysis technique and the corrective solution method, the nonlinear boundary problem is reduced to a set of algebraic equations. Numerical results exhibit the locations and extents of separation, slip, and stick zones, the interface tractions, and the energy partition. The effects of gap width, frictional coefficients, and the incident angle on the wave transmission are discussed in detail. The results show that higher harmonics are generated due to the local contact/slip at the interface. 展开更多
关键词 harmonic wave micro gap frictional contact Fourier analysis
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BLOCK PIVOT METHODS FOR SOLVING FRICTIONAL CONTACT PROBLEMS
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作者 陈万吉 陈国庆 冯恩民 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1995年第1期51-58,共8页
Based on elementary group theory, the block pivot methods for solving two-dimensional elastic frictional contact problems are presented in this paper. It is proved that the algorithms converge within a finite number o... Based on elementary group theory, the block pivot methods for solving two-dimensional elastic frictional contact problems are presented in this paper. It is proved that the algorithms converge within a finite number of steps when the friction coefficient is ''relative small''. Unlike most mathematical programming methods for contact problems, the block pivot methods permit multiple exchanges of basic and nonbasic variables. 展开更多
关键词 ELASTIC frictional contact TRIAL AND ERROR METHOD MATHEMATICAL PROGRAMMING METHOD BLOCK PIVOT METHOD CONVERGENCE
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A NEW METHOD FOR SOLUTION OF 3D ELASTIC-PLASTIC FRICTIONAL CONTACT PROBLEMS
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作者 张洪武 钟万勰 顾元宪 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第7期756-765,共10页
The solution of 3 D elastic-plastic frictional contact problems belongs to the un specified boundary problems where the interaction between two kinds of nonlinearities should occur. Considering the difficulties for th... The solution of 3 D elastic-plastic frictional contact problems belongs to the un specified boundary problems where the interaction between two kinds of nonlinearities should occur. Considering the difficulties for the solution of 3 D frictional contact problems, the key part is the determination of the tangential slip states at the contact points, and a great amount of computing work is needed for a high accuracy result. A new method based on a combination of programming and iteration methods, which are respectively known as two main kinds of methods for contact analysis, was put forward to deal with 3 D elastic-plastic contact problems. Numerical results demonstrate the efficiency of the algorithm illustrated here. 展开更多
关键词 3D frictional contact ELASTO-PLASTICITY programming method iteration method the finite element method
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Frictional contact problem for elastic-viscoplastic materials with thermal effect
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作者 M. SELMANI L. SELMANI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第6期761-776,共16页
A dynamic contact problem for elastic-viscoplastic materials with thermal effects is investigated. The contact is bilateral, and the friction is modeled with Tresca's friction law with heat exchange. A variational fo... A dynamic contact problem for elastic-viscoplastic materials with thermal effects is investigated. The contact is bilateral, and the friction is modeled with Tresca's friction law with heat exchange. A variational formulation of the model is derived, and the existence of a unique weak solution is proved. The proofs are based on the classical result of nonlinear first order evolution inequalities, the equations with monotone operators, and the fixed point arguments. Finally, the continuous dependence of the solution on the friction yield limit is studied. 展开更多
关键词 thermo-elasto-viscoplastic material dynamic process bilateral contact Tresca's friction evolution inequality evolution equation weak solution fixed point
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Contact engineering for two-dimensional semiconductors
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作者 Peng Zhang Yiwei Zhang +3 位作者 Yi Wei Huaning Jiang Xingguo Wang Yongji Gong 《Journal of Semiconductors》 EI CAS CSCD 2020年第7期7-22,共16页
Two-dimensional(2D)layered materials,including graphene,black phosphorus(BP)and transition metal dichalcogenide(TMD)such as molybdenum disulfide(Mo S2),tungsten diselenide(WSe2),have attracted increasing attention for... Two-dimensional(2D)layered materials,including graphene,black phosphorus(BP)and transition metal dichalcogenide(TMD)such as molybdenum disulfide(Mo S2),tungsten diselenide(WSe2),have attracted increasing attention for the application in electronic and optoelectronic devices.Contacts,which are the communication links between these 2D materials and external circuitry,have significant effects on the performance of electronic and optoelectronic devices.However,the performance of devices based on 2D semiconductors(SCs)is often limited by the contacts.Here,we provide a comprehensive overview of the basic physics and role of contacts in 2D SCs,elucidating Schottky barrier nature and Fermi level pinning effect at metal/2D SCs contact interface.The progress of contact engineering,including traditional metals contacts and metallic 2D materials contacts,for improving the performance of 2D SCs based devices is presented.Traditional metal contacts,named 3D top and edge contacts,are discussed briefly.Meanwhile,methods of building 2D materials contacts(2D top contact and 2D edge contact)are discussed in detail,such as chemical vapor deposition(CVD)growth of 2D metallic material contacts,phase engineered metallic phase contacts and intercalation induced metallic state contacts.Finally,the challenges and opportunities of contact engineering for 2D SCs are outlined. 展开更多
关键词 two-dimensional materials contact engineering Schottky barrier Fermi level pinning HETEROSTRUCTURES
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F0RMULATION OF BOUNDARY ELEMENT-LINEAR COMPLEMENTARY EQUATION FOR THE FRICTIONAL ELASTIC CONTACT PROBLEMS
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作者 Sha De-song Sun Huan-chun Xu Shou-ze 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第12期1105-1112,共8页
Boundary element-linear complementary equations are formulated to solve elastic contact problems with Coulomb frictions.It is also a new attempt to solve free boundary problems in solid mechanics by means of boundary ... Boundary element-linear complementary equations are formulated to solve elastic contact problems with Coulomb frictions.It is also a new attempt to solve free boundary problems in solid mechanics by means of boundary element-mathematical programming techniques. 展开更多
关键词 frictional contact linear complementary variational inequality boundary element
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RATE OF INTRA-MOLECULAR CONTACT FORMATION IN SHORT TWO-DIMENSIONAL COMPACT POLYMERS CHAINS
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作者 Jin Chen Lin-xi Zhang A-gen Xia 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第1期13-19,共7页
It is important to know the rate of intra-molecular contact formation in proteins in order to understand how proteins fold clearly. Here we investigate the rate of intra-molecular contact formation in short two-dimens... It is important to know the rate of intra-molecular contact formation in proteins in order to understand how proteins fold clearly. Here we investigate the rate of intra-molecular contact formation in short two-dimensional compact polymer chains by calculating the probability distribution p(r) of end-to-end distance r using the enumeration calculation method and HP model on two-dimensional square lattice. The probability distribution of end-to-end distance p(r) of short two-dimensional compact polymers chains may consist of two parts, i.e. p(r) = p1(r) + p2(r), where p1(r) and p2(r) are different for small r. The rate of contact formation decreases monotonically with the number of bonds N, and the rate approximately conforms to the scaling relation of k(N)∝ N^-α. Here the value of α increases with the contact radius a and it also depends on the percentage of H (hydrophobic) residues in the sequences of compact chains and the energy parameters of ^εНН、 ^εНН and ^εpp. Some comparisons of theoretical predictions with experimental results are also made. This investigation may help us to understand the protein folding. 展开更多
关键词 two-dimensional compact polymer HP model Rate of contact formation.
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EFFECT OF FRICTIONAL FORCE ON GEARING CONTACT FATIGUE STRENGTH
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作者 QI Xiumei GAO Chuangkuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期40-43,共4页
The model for computing frictional coefficient between two teeth faces at the state of mixed elastohydrodynamic lubrication is established. And then more than 80 sets of numerical calculations and six sets of disc fat... The model for computing frictional coefficient between two teeth faces at the state of mixed elastohydrodynamic lubrication is established. And then more than 80 sets of numerical calculations and six sets of disc fatigue tests are completed. The results show that when the film thickness ratio λ 〈1.6, frictional coefficient μ is drastically decreased as λ. rises; Thereafter it decreases smoothly until λ=4.5. When λ〉4.5, however, it goes up again with λ, which indicates that the excessive film thickness ratio will deteriorate gearing contact fatigue strength. At the end, the formulae for determining the frictional coefficients are formed. 展开更多
关键词 Involute spur gear contact fatigue strength Mixed elastohydrodynamic lubrication frictional coefficient Fatigue tests
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