The Experts below are selected from a list of 32013 Experts worldwide ranked by ideXlab platform
A Raeymaekers - One of the best experts on this subject based on the ideXlab platform.
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the accuracy of the compressible Reynolds Equation for predicting the local pressure in gas lubricated textured parallel slider bearings
Tribology International, 2014Co-Authors: Mingfeng Qiu, Ia N Ailey, Rob Stoll, A RaeymaekersAbstract:The validity of the compressible Reynolds Equation to predict the local pressure in a gas-lubricated, textured parallel slider bearing is investigated. The local bearing pressure is numerically simulated using the Reynolds Equation and the Navier–Stokes Equations for different texture geometries and operating conditions. The respective results are compared and the simplifying assumptions inherent in the application of the Reynolds Equation are quantitatively evaluated. The deviation between the local bearing pressure obtained with the Reynolds Equation and the Navier–Stokes Equations increases with increasing texture aspect ratio, because a significant cross-film pressure gradient and a large velocity gradient in the sliding direction develop in the lubricant film. Inertia is found to be negligible throughout this study.
Mingfeng Qiu - One of the best experts on this subject based on the ideXlab platform.
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the accuracy of the compressible Reynolds Equation for predicting the local pressure in gas lubricated textured parallel slider bearings
Tribology International, 2014Co-Authors: Mingfeng Qiu, Ia N Ailey, Rob Stoll, A RaeymaekersAbstract:The validity of the compressible Reynolds Equation to predict the local pressure in a gas-lubricated, textured parallel slider bearing is investigated. The local bearing pressure is numerically simulated using the Reynolds Equation and the Navier–Stokes Equations for different texture geometries and operating conditions. The respective results are compared and the simplifying assumptions inherent in the application of the Reynolds Equation are quantitatively evaluated. The deviation between the local bearing pressure obtained with the Reynolds Equation and the Navier–Stokes Equations increases with increasing texture aspect ratio, because a significant cross-film pressure gradient and a large velocity gradient in the sliding direction develop in the lubricant film. Inertia is found to be negligible throughout this study.
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the validity of the compressible Reynolds Equation for gas lubricated textured parallel slider bearings
ASME STLE 2012 International Joint Tribology Conference IJTC 2012, 2012Co-Authors: Mingfeng Qiu, Rob Stoll, Brian N Bailey, Bart RaeymaekersAbstract:The Navier-Stokes and compressible Reynolds Equations are solved for gas lubricated textured parallel slider bearings under hydrodynamic lubrication for a range of realistic texture geometry parameters and operating conditions. The simplifying assumptions inherent in the Reynolds Equation are validated by comparing simulation results to the solution of the Navier-Stokes Equations. Using the Reynolds Equation to describe shear driven gas flow in textured parallel slider bearings is justified for the range of parameters considered.Copyright © 2012 by ASME
Carlos Vazquez - One of the best experts on this subject based on the ideXlab platform.
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micro roughness effects in elasto hydrodynamic lubrication including a mass flow preserving cavitation model
Tribology International, 2006Co-Authors: Guy Bayada, Sebastien Martin, Carlos VazquezAbstract:An average Reynolds Equation is proposed for predicting the effects of deterministic periodic roughness, taking JFO mass flow preserving cavitation model and elastohydrodynamic effects into account. For this, the asymptotic model is based upon a double scale analysis approach. The average Reynolds Equation can be used both for the description of cavitation on a macroscopic scale in widening gap regions as well as for cavitation on the microscopic interasperity scale. Results of numerical simulations based on the model are presented for the case of a hydrodynamically lubricated journal bearings and an elasto-hydrodynamically lubricated point contact.
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an average flow model of the Reynolds roughness including a mass flow preserving cavitation model
Journal of Tribology-transactions of The Asme, 2005Co-Authors: Guy Bayada, Sebastien Martin, Carlos VazquezAbstract:An average Reynolds Equation for predicting the effects of deterministic periodic roughness, taking Jakobsson, Floberg, and Olsson mass flow preserving cavitation model into account, is introduced based upon the double scale analysis approach. This average Reynolds Equation can be used both for a microscopic interasperity cavitation and a macroscopic one. The validity of such a model is verified by numerical experiments both for one-dimensional and two-dimensional roughness patterns.
Dominique Bonneau - One of the best experts on this subject based on the ideXlab platform.
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IJTC2007-44260 EHD LUBRICATION OF MULTI-BODY COMMON-PIN CONROD BIG END BEARINGS SYSTEM
2020Co-Authors: Aurelian Fatu, Dominique BonneauAbstract:ABSTRACT This paper describes a model for the analysis of elastohydrodynamic (EHD) lubrication of a multi-body common-pin connecting-rod (conrod) big end bearing system. Two conrod and three thrust bearings are fully coupled in order to simulate real behavior of the system. An extended Reynolds Equation including mass conservation and oil film history is solved in the big end conrod bearings. The HD behavior of the thrust bearings is simulated by a cylindrical coordinate Reynolds Equation. By comparisons with classical single rod analysis results show the pertinancy of simulating twin moving conrods. INTRODUCTION The importance of considering conrod housing and pin flexibility has been widely discussed and demonstrated by several authors In order to investigate this problem, a model based on Finite Element discretization method (FEM) is proposed. The film Reynolds Equation (in the two bearings and the three thrust bearings) but also the system structure is discretized by FEM. Thus, the hydrodynamic problem is fully coupled with the conrod and shaft structure deformation. To demonstrate the approach, two conrod bearings with a common-pin in a high-speed racing engine are simulated. Comparisons are made between a single moving rod and twin moving rods
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computing hydrodynamic pressure in mixed lubrication by modified Reynolds Equation
Proceedings of the Institution of Mechanical Engineers Part J: Journal of Engineering Tribology, 2012Co-Authors: Aurelian Fatu, Dominique Bonneau, Ramona FatuAbstract:Nowadays, even with the available computing power, complete deterministic solutions of large or dynamically loaded bearings are not possible in acceptable amounts of computing time. Therefore, in order to model mixed lubrication conditions, the Reynolds Equation is modified by the introduction of flow factors that take into account the roughness effects. Patir and Cheng proposed the most known model. In their model, flow factors are obtained from the statistical parameters of the surface roughness. The flow factors can also be computed from deterministic calculation on a sample of the studied surface or by using the homogenization technique on the same surface sample. In this article, three approaches are compared. Moreover, the influence of the surface deformation due to asperity contact over the flow factors is investigated.
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EHD Lubrication of Multi-Body Common-Pin Conrod Big End Bearings System
ASME STLE 2007 International Joint Tribology Conference Parts A and B, 2007Co-Authors: Aurelian Fatu, Dominique BonneauAbstract:This paper describes a model for the analysis of elastohydrodynamic (EHD) lubrication of a multi-body common-pin connecting-rod (conrod) big end bearing system. Two conrod and three thrust bearings are fully coupled in order to simulate real behavior of the system. An extended Reynolds Equation including mass conservation and oil film history is solved in the big end conrod bearings. The HD behavior of the thrust bearings is simulated by a cylindrical coordinate Reynolds Equation. By comparisons with classical single rod analysis results show the pertinancy of simulating twin moving conrods.Copyright © 2007 by ASME
Aurelian Fatu - One of the best experts on this subject based on the ideXlab platform.
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IJTC2007-44260 EHD LUBRICATION OF MULTI-BODY COMMON-PIN CONROD BIG END BEARINGS SYSTEM
2020Co-Authors: Aurelian Fatu, Dominique BonneauAbstract:ABSTRACT This paper describes a model for the analysis of elastohydrodynamic (EHD) lubrication of a multi-body common-pin connecting-rod (conrod) big end bearing system. Two conrod and three thrust bearings are fully coupled in order to simulate real behavior of the system. An extended Reynolds Equation including mass conservation and oil film history is solved in the big end conrod bearings. The HD behavior of the thrust bearings is simulated by a cylindrical coordinate Reynolds Equation. By comparisons with classical single rod analysis results show the pertinancy of simulating twin moving conrods. INTRODUCTION The importance of considering conrod housing and pin flexibility has been widely discussed and demonstrated by several authors In order to investigate this problem, a model based on Finite Element discretization method (FEM) is proposed. The film Reynolds Equation (in the two bearings and the three thrust bearings) but also the system structure is discretized by FEM. Thus, the hydrodynamic problem is fully coupled with the conrod and shaft structure deformation. To demonstrate the approach, two conrod bearings with a common-pin in a high-speed racing engine are simulated. Comparisons are made between a single moving rod and twin moving rods
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computing hydrodynamic pressure in mixed lubrication by modified Reynolds Equation
Proceedings of the Institution of Mechanical Engineers Part J: Journal of Engineering Tribology, 2012Co-Authors: Aurelian Fatu, Dominique Bonneau, Ramona FatuAbstract:Nowadays, even with the available computing power, complete deterministic solutions of large or dynamically loaded bearings are not possible in acceptable amounts of computing time. Therefore, in order to model mixed lubrication conditions, the Reynolds Equation is modified by the introduction of flow factors that take into account the roughness effects. Patir and Cheng proposed the most known model. In their model, flow factors are obtained from the statistical parameters of the surface roughness. The flow factors can also be computed from deterministic calculation on a sample of the studied surface or by using the homogenization technique on the same surface sample. In this article, three approaches are compared. Moreover, the influence of the surface deformation due to asperity contact over the flow factors is investigated.
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EHD Lubrication of Multi-Body Common-Pin Conrod Big End Bearings System
ASME STLE 2007 International Joint Tribology Conference Parts A and B, 2007Co-Authors: Aurelian Fatu, Dominique BonneauAbstract:This paper describes a model for the analysis of elastohydrodynamic (EHD) lubrication of a multi-body common-pin connecting-rod (conrod) big end bearing system. Two conrod and three thrust bearings are fully coupled in order to simulate real behavior of the system. An extended Reynolds Equation including mass conservation and oil film history is solved in the big end conrod bearings. The HD behavior of the thrust bearings is simulated by a cylindrical coordinate Reynolds Equation. By comparisons with classical single rod analysis results show the pertinancy of simulating twin moving conrods.Copyright © 2007 by ASME
