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 On the Use of Model Order Reduction Techniques for the Elastohydrodynamic Contact Problem written by Daniel Maier and published by . This book was released on 2020-10-09 with total page 170 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. This work was published by Saint Philip Street Press pursuant to a Creative Commons license permitting commercial use. All rights not granted by the work's license are retained by the author or authors.
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 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work presents an efficient solution procedure for the elastohydrodynamic (EHD) contact problem considering structural dynamics. The contact bodies are modeled using reduced finite element models. Singly diagonal implicit Runge-Kutta (SDIRK) methods are used for adaptive time integration. The structural model is coupled with the nonlinear Reynolds Equation using a monolithic coupling approach. Finally, a reduced order model of the complete nonlinear coupled problem is constructed.
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 2018-03-21 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 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 On direct and inverse problems related to longitudinal impact of non uniform elastic rods written by Burgert, Jens and published by KIT Scientific Publishing. This book was released on 2021-05-07 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: The impact of two non-uniform elastic rods is considered and a recursive method was developed that solves the inverse problem: Find the location-dependent impedance function of the impacting rod that generates a prescribed impact force. The developed method delivers exact solutions in closed-form. Moreover, a condition is derived which states if a physically meaningful solution exists. Finally, the underlying 1D model has been validated experimentally.
Download or read book On the Influence of Piecewise Defined Contact Geometries on Friction Dampers written by Aramendiz Fuentes, Jimmy Alberto and published by KIT Scientific Publishing. This book was released on 2023-09-12 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work considers dampers that do not solely focus on a single strategy but instead combine them. The capabilities of conventional dry friction dampers are expanded by taking into account piecewise defined contact geometries. This leads to friction dampers that change their behavior depending on the amplitude of the oscillations. The vibration damping device in this work, introduces damping at high oscillation amplitudes and takes advantage of absorption at low oscillation amplitudes.
Download or read book Nonparametric identification of nonlinear dynamic systems written by Kenderi, Gábor and published by KIT Scientific Publishing. This book was released on 2018-11-11 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: A nonparametric identification method for highly nonlinear systems is presented that is able to reconstruct the underlying nonlinearities without a priori knowledge of the describing nonlinear functions. The approach is based on nonlinear Kalman Filter algorithms using the well-known state augmentation technique that turns the filter into a dual state and parameter estimator, of which an extension towards nonparametric identification is proposed in the present work.
Download or read book Lubricant transport towards tribocontact in capillary surface structures written by Klima, Joachim and published by KIT Scientific Publishing. This book was released on 2018-11-13 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: To counter lubricant shortage at a frictional contact (starvation), lubrication liquids, e.g. oils, are actively transported from a distant location towards the undersupplied tribocontact. This is done via small channels or generally via structures cut into a flat surface. In this way one can use capillary force as a cheap and reliable driver of the lubricant flow. Numerical modeling and experiments show that this method can be considered a promising new option to enhance tribocontact operation.
Download or read book Dynamics of Rotors on Refrigerant Lubricated Gas Foil Bearings written by Leister, Tim and published by KIT Scientific Publishing. This book was released on 2021-10-28 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The gas foil bearing (GFB) technology is a key factor for the transition to oil-free rotating machinery. Among numerous advantages, GFBs offer the unique ability to be lubricated with working fluids such as refrigerants. However, the computational analysis of refrigerant-lubricated GFB–rotor systems represents an interdisciplinary problem of enormous complexity. This work pushes forward existing limits of feasibility and establishes a new strategy that enables stability and bifurcation analyses.
Download or read book Crosswind stability of vehicles under nonstationary wind excitation written by Zhang, Xiaoyu and published by KIT Scientific Publishing. This book was released on 2015-05-13 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work has studied the crosswind stability of vehicles under nonstationary wind excitation in various scenarios. Railway vehicles running on curved and straight track with varying vehicle speed are studied. Road vehicles are classified into different categories. For each vehicle class, a corresponding worst-case vehicle model has been built. As the wind excitation on the vehicle is a stochastic process, a risk analysis has to be carried out and failure probabilities are computed and analyzed.
Download or read book Modeling and Simulation of Tribological Problems in Technology written by Marco Paggi and published by Springer. This book was released on 2019-06-26 with total page 335 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book conveys, in a self-contained manner, the fundamental concepts for classifying types of contact, the essential mathematical methods for the formulation of contact problems, and the numerical methods required for their solution. In addition to the methodologies, it covers a broad range of applications, including contact problems in mechanical engineering, microelectronics and nanomechanics. All chapters provide both substantial background on the theory and numerical methods, and in-depth treatments of cutting-edge research topics and applications. The book is primarily intended for doctoral students of applied mathematics, mechanics, engineering and physics with a strong interest in the theoretical modelling, numerical simulation and experimental characterization of contact problems in technology. It will also benefit researchers in the above mentioned and neighbouring fields working in academia or at private research and development centres who are interested in a concise yet comprehensive overview of contact mechanics, from its fundamental mathematical background, to the computational methods and the experimental techniques currently available for the solution of contact problems.
Download or read book Nonlinear Structures Systems Volume 1 written by Matthew R.W. Brake and published by Springer Nature. This book was released on 2022-07-28 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nonlinear Structures & Systems, Volume 1: Proceedings of the 40th IMAC, A Conference and Exposition on Structural Dynamics, 2022, the first volume of nine from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Nonlinear Dynamics, including papers on: Experimental Nonlinear Dynamics Jointed Structures: Identification, Mechanics, Dynamics Nonlinear Damping Nonlinear Modeling and Simulation Nonlinear Reduced-Order Modeling Nonlinearity and System Identification
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 Approximation of Large Scale Dynamical Systems written by Athanasios C. Antoulas and published by SIAM. This book was released on 2009-06-25 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mathematical models are used to simulate, and sometimes control, the behavior of physical and artificial processes such as the weather and very large-scale integration (VLSI) circuits. The increasing need for accuracy has led to the development of highly complex models. However, in the presence of limited computational accuracy and storage capabilities model reduction (system approximation) is often necessary. Approximation of Large-Scale Dynamical Systems provides a comprehensive picture of model reduction, combining system theory with numerical linear algebra and computational considerations. It addresses the issue of model reduction and the resulting trade-offs between accuracy and complexity. Special attention is given to numerical aspects, simulation questions, and practical applications.
Download or read book Contact Dynamics in the Field of Elastohydrodynamic Lubrication written by Ysbrand Hans Wijnant and published by . This book was released on 1998 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multi Level Methods in Lubrication written by C.H. Venner and published by Elsevier. This book was released on 2000-07-21 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: Efficient numerical solution of realistic and, therefore, complex equation systems occupies many researchers in many disciplines. For various reasons, but mainly in order to approximate reality, a very large number of unknowns are needed. Using classical techniques, the solution of such a system of equations would take too long, and so sometimes MultiLevel techniques are used to accelerate convergence. Over the last one and a half decades, the authors have studied the problem of Elastohydrodynamic Lubrication, governed by a complex integro-differential equation. Their work has resulted in a very efficient and stable solver. In this book they describe the different intermediate problems analyzed and solved, and how those ingredients finally come together in the EHL solver. A number of these intermediate problems, such as Hydrodynamic Lubrication and Dry Contact, are useful in their own right. In the Appendix the full codes of the Poisson problem, the Hydrodynamic Lubrication problem, the dry contact solver and the EHL solver are given. These codes are all written in 'C' language, based on the 'ANSI-C' version.
