Download or read book Transient Vibration Prediction for Rotors on Ball Bearings Using Load Dependent Non Linear Bearing Stiffness written by National Aeronautics and Space Adm Nasa and published by . This book was released on 2018-09-27 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rolling-element bearing forces vary nonlinearly with bearing deflection. Thus an accurate rotordynamic transient analysis requires bearing forces to be determined at each step of the transient solution. Analyses have been carried out to show the effect of accurate bearing transient forces (accounting for non-linear speed and load dependent bearing stiffness) as compared to conventional use of average rolling-element bearing stiffness. Bearing forces were calculated by COBRA-AHS (Computer Optimized Ball and Roller Bearing Analysis - Advanced High Speed) and supplied to the rotordynamics code ARDS (Analysis of Rotor Dynamic Systems) for accurate simulation of rotor transient behavior. COBRA-AHS is a fast-running 5 degree-of-freedom computer code able to calculate high speed rolling-element bearing load-displacement data for radial and angular contact ball bearings and also for cylindrical and tapered roller beatings. Results show that use of nonlinear bearing characteristics is essential for accurate prediction of rotordynamic behavior. Fleming, David P. and Poplawski, J. V. Glenn Research Center NASA/TM-2002-211829, NAS 1.15:211829, E-13523...
Download or read book Unbalance Response Prediction for Rotors on Ball Bearings Using Speed and Load Dependent Nonlinear Bearing Stiffness written by and published by . This book was released on 2003 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the 10th International Conference on Rotor Dynamics IFToMM written by Katia Lucchesi Cavalca and published by Springer. This book was released on 2018-08-20 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: IFToMM conferences have a history of success due to the various advances achieved in the field of rotor dynamics over the past three decades. These meetings have since become a leading global event, bringing together specialists from industry and academia to promote the exchange of knowledge, ideas, and information on the latest developments in the dynamics of rotating machinery. The scope of the conference is broad, including e.g. active components and vibration control, balancing, bearings, condition monitoring, dynamic analysis and stability, wind turbines and generators, electromechanical interactions in rotor dynamics and turbochargers. The proceedings are divided into four volumes. This first volume covers the following main topics: Active Components and Vibration Control; Balancing; Bearings: Fluid Film Bearings, Magnetic Bearings, Rolling Bearings and Seals; and Blades, Bladed Systems and Impellers.
Download or read book Dynamics of Rotors and Foundations written by Erwin Krämer and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rotordynamics are of great importance in the design, manufacture and assembly of turbomachines as well as in ensuring their safe operation. Also important are the dynamics of the foundation and its interaction with the dynamics of the rotor. This book is divided into four parts. Following a presentation of the basic theory the dynamics of rotors supported on several bearings. The third part describes the dynamics of foundations of turbine line-outs and the calculations for a turbomachine coupled with its foundation. The last part includes a section on estimation procedures, a comprehensive presentation of the theoryand practice of rotors having a transverse crack, a section on the mathematical fundamentals and a description of the computer program used for the examples in the book. The book addresses both the practical engineer and the theoretician and should provide manufacturers, operators, university and polytechnic lecturers and students with an understanding of the vibrations of turbomachines. The results are described in such a way that they can be easily understood and applied.
Download or read book Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conferences 2005 written by and published by . This book was released on 2005 with total page 944 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 2004 with total page 1102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Unbalance Response Prediction for Accelerating Rotors with Load Dependent Nonlinear Bearing Stiffness written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rolling-element bearing forces vary nonlinearly with bearing deflection. Thus an accurate rotordynamic analysis requires that bearing forces corresponding to the actual bearing deflection be utilized. Previous papers have explored the transient effect of suddenly applied imbalance and the steady-state unbalance response, using bearing forces calculated by the rolling-element bearing analysis code COBRA-AHS. The present work considers the acceleration of a rotor through one or more critical speeds. The rotordynamic analysis showed that for rapid acceleration rates the maximum response amplitude may be considerably less than predicted by steady-state analysis. Above the critical speed, transient vibration at the rotor natural frequency occurs, similar to that predicted for a Jeffcott rotor with constant-stiffness bearings. A moderate amount of damping will markedly reduce the vibration amplitude, but this damping is not inherent in ball bearings. Fleming, David P. and Sawicki, Jaezy T. and Poplawski, J. V. Glenn Research Center NASA/TM-2005-213801, E-15159
Download or read book Rotordynamics of Turbomachinery written by John M. Vance and published by John Wiley & Sons. This book was released on 1991-01-16 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes the rotordynamic considerations that are important to the successful design or troubleshooting of a turbomachine. Shows how bearing design, fluid seals, and rotor geometry affect rotordynamic behavior (vibration, shaft whirling, bearing loads, and critical speeds), and describes two successful computational methods for rotordynamic analysis in terms that can be understood by practicing engineers. Gives descriptive accounts of the state of the art in several areas of the field and presents important mathematical or computational concepts, describing equations and formulas in physical terms for better understanding. Also offers tips for troubleshooting unstable machines and provides practical interpretations of vibration measurements.
Download or read book Dynamics of Rotating Machines written by M. I. Friswell and published by Cambridge University Press. This book was released on 2010-03-31 with total page 545 pages. Available in PDF, EPUB and Kindle. Book excerpt: Enables engineers to understand the dynamics of rotating machines, from basic explanations to detailed numerical models and analysis.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1979 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1987 with total page 1124 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MARE WINT written by Wiesław Ostachowicz and published by Springer. This book was released on 2016-08-30 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a holistic, interdisciplinary overview of offshore wind energy, and is a must-read for advanced researchers. Topics, from the design and analysis of future turbines, to the decommissioning of wind farms, are covered. The scope of the work ranges from analytical, numerical and experimental advancements in structural and fluid mechanics, to novel developments in risk, safety & reliability engineering for offshore wind.The core objective of the current work is to make offshore wind energy more competitive, by improving the reliability, and operations and maintenance (O&M) strategies of wind turbines. The research was carried out under the auspices of the EU-funded project, MARE-WINT. The project provided a unique opportunity for a group of researchers to work closely together, undergo multidisciplinary doctoral training, and conduct research in the area of offshore wind energy generation. Contributions from expert, external authors are also included, and the complete work seeks to bridge the gap between research and a rapidly-evolving industry.
Download or read book Dynamics of Rotors written by O. Mahrenholtz and published by Springer. This book was released on 2014-05-04 with total page 501 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Introduction to Dynamics of Rotor bearing Systems written by Wen Jeng Chen and published by Trafford on Demand Pub. This book was released on 2007 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is written as an introduction to rotor-bearing dynamics for practicing engineers and students who are involved in rotordynamics and bearing design. The goal of this book is to provide a step-by-step approach to the understanding of fundamentals of rotor-bearing dynamics by using DyRoBeS(c) . Therefore, the emphasis of this book is on the basic principals, phenomena, modeling, and interpretation of the results. Numerous examples, from a single-degree-of-freedom system to complicated industrial rotating machinery, are employed throughout this book to illustrate these fundamental dynamic behaviors. The concepts in the text are reinforced by parametric studies and numerous illustrative examples and figures. The book begins with a brief discussion of the mathematical modeling of physical dynamic systems and an overview of the basic vibration concepts in Chapter 1. The coordinate systems and the kinematics of the rotor motion are presented in Chapter 2. A simple two-degrees-of-freedom rotor system, the Laval-Jeffcott rotor model, is utilized in Chapter 3 to demonstrate many important phenomena in rotordynamics. This simple 2DOF model provides many valuable physical insights into more practical and complicated systems. Chapter 4 discusses the rotating disk equations and rigid rotor dynamics. Chapter 5 covers the finite element formulation for a rotating shaft element. Chapter 6 deals with various types of bearings, dampers, seals and other interconnection components. All the reaction forces from these components are non-linear in nature. The concept of linearization around the static equilibrium is discussed. Chapter 7 summarizes the lateral vibration study with several practical examples. Various solution techniques and interpretation of the results are discussed. Chapter 8 is devoted to the important subject of torsional vibration. Finally, a brief description of the balancing method, influence coefficient method is presented in Chapter 9.
Download or read book Essential Concepts of Bearing Technology written by Tedric A. Harris and published by CRC Press. This book was released on 2006-10-09 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: Part of the fifth edition of the classic Rolling Bearing Analysis, this book builds a basic understanding of the fundamentals underlying the use, design, and performance of rolling bearings. It serves as a stand-alone introduction cutting across the array of disciplines necessary to evaluate and comprehend the performance and behavior of all types of rolling bearings. The authors derive the mathematics and theories underlying catalog values given by manufacturers and lead you from the various types of bearings through bearing geometry, applied loading, internal load distribution, deformation, functional performance, and structural materials. It makes an ideal introductory textbook as well as a practical field reference for professionals.
Download or read book Dynamics of Rotating Systems written by Giancarlo Genta and published by Springer Science & Business Media. This book was released on 2007-01-04 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides an up-to-date review of rotor dynamics, dealing with basic topics as well as a number of specialized topics usually available only in journal articles Unlike other books on rotordynamics, this treats the entire machine as a system, with the rotor as just one component