Download or read book A Full system Finite Element Approach to Elastohydrodynamic Lubrication Problems written by Wassim Habchi and published by . This book was released on 2008 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, a full-system finite element approach to elastohydrodynamic (EHD) lubrication problems is introduced. EHD lubrication is a full-film regime where the pressure generated in the conjunction is high enough to induce a significant elastic deformation of the contacting bodies. Hence, it involves a strong coupling between hydrodynamic and elastic effects. The non-linear system formed by the Reynolds', linear elasticity and load balance equations is solved using a fully-coupled Newton-Raphson procedure. This approach provides outstanding convergence rates when compared with the semi-system one. A penalty method is used to handle the cavitation problem that arises at the outlet of the contact. Appropriate stabilized formulations are used to extend the solution to the case of highly loaded contacts. The resolution process is then extended to account for non-Newtonian behaviour of the lubricant and for thermal effects. The developed model is used to study the behaviour of EHD contacts lubricated with Ultra-Low-Viscosity Fluids. The use of such fluids as lubricants provides two main advantages: first, the frictional energy dissipation in the contact is reduced and second, in machines that work with a low viscosity operational fluid and a lubricant, the former can be used to fulfil both functions and thus the design and maintenance of such machines would become easier and their performance would be improved.
Download or read book Finite Element Modeling of Elastohydrodynamic Lubrication Problems written by Wassim Habchi and published by John Wiley & Sons. This book was released on 2018-07-23 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covers the latest developments in modeling elastohydrodynamic lubrication (EHL) problems using the finite element method (FEM) This comprehensive guide introduces readers to a powerful technology being used today in the modeling of elastohydrodynamic lubrication (EHL) problems. It provides a general framework based on the finite element method (FEM) for dealing with multi-physical problems of complex nature (such as the EHL problem) and is accompanied by a website hosting a user-friendly FEM software for the treatment of EHL problems, based on the methodology described in the book. Finite Element Modeling of Elastohydrodynamic Lubrication Problems begins with an introduction to both the EHL and FEM fields. It then covers Standard FEM modeling of EHL problems, before going over more advanced techniques that employ model order reduction to allow significant savings in computational overhead. Finally, the book looks at applications that show how the developed modeling framework could be used to accurately predict the performance of EHL contacts in terms of lubricant film thickness, pressure build-up and friction coefficients under different configurations. Finite Element Modeling of Elastohydrodynamic Lubrication Problems offers in-depth chapter coverage of Elastohydrodynamic Lubrication and its FEM Modeling, under Isothermal Newtonian and Generalized-Newtonian conditions with the inclusion of Thermal Effects; Standard FEM Modeling; Advanced FEM Modeling, including Model Order Reduction techniques; and Applications, including Pressure, Film Thickness and Friction Predictions, and Coated EHL. This book: Comprehensively covers the latest technology in modeling EHL problems Focuses on the FEM modeling of EHL problems Incorporates advanced techniques based on model order reduction Covers applications of the method to complex EHL problems Accompanied by a website hosting a user-friendly FEM-based EHL software Finite Element Modeling of Elastohydrodynamic Lubrication Problems is an ideal book for researchers and graduate students in the field of Tribology.
Download or read book Efficient Finite Element Simulation of Full system Elastohydrodynamic Lubrication Problems written by Sarfraz Ahmed and published by . This book was released on 2012 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is concerned with the efficient numerical solution of problems of elastohydrodynamic lubrication (EHL). Our approach is to consider fully-coupled models in which the governing equations for the lubricating film, the elastic deformation and the force balance are each discretized and solved as a single monolithic nonlinear system of algebraic equations. The main contributions of this work are to propose, implement and analyse a novel, optimal, preconditioner for the Newton linearization of this algebraic system, and to assess the development of efficient finite element meshes through both manual tuning and the use of adaptive mesh refinement based upon a posteriori error estimation and control. Throughout this work, we employ first order finite element discretizations for both the Reynolds equation (for the lubricant) and for the linear elasticity model on a finite domain. The resulting nonlinear algebraic equations are then solved using a quasi-Newton algorithm. For each linear solve a Krylov subspace method is used and a new blockwise preconditioner is presented which is designed to exploit the specific structure that is present in this class of problem. This preconditioner combines the use of multigrid preconditioning for the elasticity block and a separate, efficient, approximation to precondition the Reynolds block. The solver developed in this work can be distinguished into two variants based upon the use of algebraic and geometric multigrid preconditioning of the elasticity block. Numerical results are presented both for line and point contact problems to validate the implementations and to allow a comparison of the performance and efficiency of the proposed solution strategies compared to the use of a state-of-the-art sparse direct solver at each Newton step. These results demonstrate that the preconditioned iterative approach is both computationally and memory superior to the sparse direct solver. Most importantly, both the computational and memory costs are seen to grow linearly with the number of unknowns. A locally adaptive solution scheme is also developed for fully-coupled EHL point contact problems. This automates the refinement process to the regions of the domain which exhibit large error in their solutions. Numerical results are presented which demonstrate the performance and effectiveness of the proposed procedure.
Download or read book An efficient solution procedure for elastohydrodynamic contact problems considering structural dynamics written by Schmidt, Jan Henrik and published by KIT Scientific Publishing. This book was released on 2019-01-14 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Finite Element Modeling of Elastohydrodynamic Lubrication Problems written by Wassim Habchi and published by John Wiley & Sons. This book was released on 2018-03-13 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covers the latest developments in modeling elastohydrodynamic lubrication (EHL) problems using the finite element method (FEM) This comprehensive guide introduces readers to a powerful technology being used today in the modeling of elastohydrodynamic lubrication (EHL) problems. It provides a general framework based on the finite element method (FEM) for dealing with multi-physical problems of complex nature (such as the EHL problem) and is accompanied by a website hosting a user-friendly FEM software for the treatment of EHL problems, based on the methodology described in the book. Finite Element Modeling of Elastohydrodynamic Lubrication Problems begins with an introduction to both the EHL and FEM fields. It then covers Standard FEM modeling of EHL problems, before going over more advanced techniques that employ model order reduction to allow significant savings in computational overhead. Finally, the book looks at applications that show how the developed modeling framework could be used to accurately predict the performance of EHL contacts in terms of lubricant film thickness, pressure build-up and friction coefficients under different configurations. Finite Element Modeling of Elastohydrodynamic Lubrication Problems offers in-depth chapter coverage of Elastohydrodynamic Lubrication and its FEM Modeling, under Isothermal Newtonian and Generalized-Newtonian conditions with the inclusion of Thermal Effects; Standard FEM Modeling; Advanced FEM Modeling, including Model Order Reduction techniques; and Applications, including Pressure, Film Thickness and Friction Predictions, and Coated EHL. This book: Comprehensively covers the latest technology in modeling EHL problems Focuses on the FEM modeling of EHL problems Incorporates advanced techniques based on model order reduction Covers applications of the method to complex EHL problems Accompanied by a website hosting a user-friendly FEM-based EHL software Finite Element Modeling of Elastohydrodynamic Lubrication Problems is an ideal book for researchers and graduate students in the field of Tribology.
Download or read book High Order Finite Element Solution of Elastohydrodynamic Lubrication Problems written by Hongqiang Lu and published by . This book was released on 2006 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transient Elastohydrodynamic Lubrication Analysis by Finite Element Methods written by Chi-Fan Shu and published by . This book was released on 1981 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Systems of finite elements in lubrication written by Paul E. Allaire and published by . This book was released on 1975 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Elastohydrodynamic Lubrication Transient Finite Element Analysis written by Chia Peng Day and published by . This book was released on 1974 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Solution of the Thermal Elastohydrodynamic Lubrication Problem by Use of the Finite Element Method written by Richard Thornton Cartwright and published by . This book was released on 1984 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Finite Element Method for the Solution of Three dimensional Thermohydrodynamics Lubrication Problems written by Lawrence R. Gero and published by . This book was released on 1986 with total page 165 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Elasto Hydrodynamic Lubrication written by D. Dowson and published by Elsevier. This book was released on 2014-07-18 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elasto-Hydrodynamic Lubrication deals with the mechanism of elasto-hydrodynamic lubrication, that is, the lubrication regime in operation over the small areas where machine components are in nominal point or line contact. The lubrication of rigid contacts is discussed, along with the effects of high pressure on the lubricant and bounding solids. The governing equations for the solution of elasto-hydrodynamic problems are presented. Comprised of 13 chapters, this volume begins with an overview of elasto-hydrodynamic lubrication and representation of contacts by cylinders, followed by a discussion on equations relevant to lubrication, including the Reynolds equation. The reader is then introduced to lubrication of rigid cylinders; the importance of film thickness in highly loaded rigid contacts; the elasticity of solids in contact; and the theory of elasto-hydrodynamic lubrication. Subsequent chapters focus on apparatus and measurements of film thickness and film shape; friction and viscosity; and lubrication of gears and roller bearings. This book will be of interest to tribologists.
Download or read book Elastohydrodynamic Lubrication Analysis of Dynamically Loaded Journal Bearings written by Arun Kumar and published by . This book was released on 1988 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Calculation of Elastohydrodynamic Lubrication written by Ping Huang and published by John Wiley & Sons. This book was released on 2015-09-21 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book not only offers scientists and engineers a clear inter-disciplinary introduction and orientation to all major EHL problems and their solutions but, most importantly, it also provides numerical programs on specific application in engineering. • A one-stop reference providing equations and their solutions to all major elastohydrodynamic lubrication (EHL) problems, plus numerical programs on specific applications in engineering • offers engineers and scientists a clear inter-disciplinary introduction and a concise program for practical engineering applications to most important EHL problems and their solutions • brings together a number of case studies in one text, each being solved using solution methods which share common features and methods
Download or read book Elastohydrodynamic Lubrication for Line and Point Contacts written by Ilya I. Kudish and published by CRC Press. This book was released on 2013-06-17 with total page 714 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elastohydrodynamic Lubrication for Line and Point Contacts: Asymptotic and Numerical Approaches describes a coherent asymptotic approach to the analysis of lubrication problems for heavily loaded line and point contacts. This approach leads to unified asymptotic equations for line and point contacts as well as stable numerical algorithms for the solution of these elastohydrodynamic lubrication (EHL) problems. A Unique Approach to Analyzing Lubrication Problems for Heavily Loaded Line and Point Contacts The book presents a robust combination of asymptotic and numerical techniques to solve EHL problems for lightly and heavily loaded line and point contacts. It also proposes a reasonably simple and naturally based regularization approach that produces stable solutions in heavily loaded EHL contacts. The book offers a clear understanding of the processes taking place in heavily loaded line and point EHL contacts as well as of the proper solution structure for EHL problems. It outlines concrete ways to determine important design parameters such as lubrication film thickness and frictional stresses and forces. The book establishes a close link between EHL problems for heavily loaded point and line contacts. Fine Tune Your Methods for Solving Elastohydrodynamic Lubrication Problems In most cases, the equations in the book are derived from first principles. The author describes each of the asymptotic and numerical methods in detail, making it easier for readers to apply them to various problems. The problem solutions are presented in the form of simple analytical formulas, graphs, and tables. Almost all the chapters include exercises that highlight key points and skills. Suitable for engineering and applied mathematics students, this is also a unique resource for researchers and practitioners who want to fine tune their solution methods and design better numerical methods to tackle elastohydrodynamic lubrication problems.
Download or read book On the Use of Model Order Reduction Techniques for the Elastohydrodynamic Contact Problem written by Maier, Daniel and published by KIT Scientific Publishing. This book was released on 2015-05-12 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this work is to develop a method which solves the nonlinear elastohydrodynamic contact problem in a fast and precise way using model order reduction techniques. The reduction procedure is based on a projection onto a low-dimensional subspace using different hyper-reduction procedures. The method provides fast and highly accurate reduced order models for stationary and transient, Newtonian and Non-Newtonian EHD line and point contact problems.
Download or read book The Finite Element Method for Mechanics of Solids with ANSYS Applications written by Ellis H. Dill and published by CRC Press. This book was released on 2011-08-25 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt: While the finite element method (FEM) has become the standard technique used to solve static and dynamic problems associated with structures and machines, ANSYS software has developed into the engineer's software of choice to model and numerically solve those problems. An invaluable tool to help engineers master and optimize analysis, The Finite El
