An introduction to the influence of the bearings on the dynamics of rotating machinery a. The modeling and analysis of rotorbearing dynamics are now reached a mature state. Introduction for years linear transfer matrix programs have been used by rotating machinery engineers for estimating critical speeds and predicting stability of complex rotorbearing systems. Introduction to dynamics of rotor bearing systems john pagan. Following an initial definition of the term model, a summary of a successful system dynamics intervention is described. The goal of this book is to provide a stepbystep approach to the understanding of fundamentals of rotor bearing dynamics by using dyrobes. The springlike connections to ground denote the bearing and seal elements supporting the rotor. Notes 0 introduction to fluid film bearings and seals. Rotordynamics, also known as rotor dynamics, is a specialized branch of applied mechanics concerned with the behavior and diagnosis of rotating structures.
Introduction to rotor dynamics request pdf researchgate. Rotor bearing solutions international a company with. Fundamental understanding of dynamic instability in rotors 4 instability in rotor bearing systems a. This paper deals with the influence of bearing asymmetry on the stability characteristics of a rotor under the influence of internal friction and aerodynamic cross coupling forces. W j chen and j e gunter, introduction to dynamics of rotor bearing systems, trafford publishing ltd. Just released in 2015, this indispensable text is designed for the practicing engineer, and provides the basic theory, design principles and detailed examples to. Introduction equations of motion structural analysis case studies references outline 2 27 1 introduction structures of interest. This site is a gateway to technical literature on rotordynamics, including an online database of over 26,000 technical papers presented at conferences related to rotordynamics worldwide since 1974. Stepbystep rotorbearing system modeling, analysis, and problem solution by the introduction of rotor dynamics software and its application to a rotorbearing system. The adequate operation of a turbomachine is defined by its ability to tolerate normal and.
This is caused by nonlinear squeeze film dampers, rolling element bearings, or. This background will be helpful in the identification. It is desired to increase airflow and power output without increasing physical size. The damping ratio represents the ratio of rotor damping to the system critical damping. Introduction to dynamics of rotorbearing systems 9781412051903. Dynamics of rotorbearing systems using finite elements page 2 of 11 the xyz and xyz triads are the fixed. Rao, vibratory condition monitoring of machines, narosa publishing house. Rotordynamic analysis is a crucial step in the development of rotor bearing systems. This report is an update of the original part iv of the rotorbearing dynamics design technology series, afapltr6545 parts i through x. In this chapter we present a short introduction to rotor dynamics to familiarize the reader with the basic concepts and terminologies commonly used in describing rotoramb systems. The wellknown symmetric dufrane bearing wear model is used here.
Rotor bearing, finite element method, campbell diagram, natural frequency. This book is written as an introduction to rotorbearing dynamics for practicing engineers and students who are involved in rotordynamics and bearing design. Mechanical engineering national institute of technology rourkela november 10, 2016 supervisors certificate this is to certify that the work presented in this dissertation entitled dynamic analysis. Introduction to dynamics of rotorbearing systems wen jeng chen, edgar m. Introduction to dynamics of rotor bearing systems youtube. First, the mathematics behind the basic rotordynamic principles are derived by introducing a simple rotorbearing system known as the foppljeffcott rotor. Bearing interaction with the rotating assembly, oilwhirlwhip phenomena, rotorbearing response, and. The concepts in the text are reinforced by parametric studies and numerous illustrative examples and figures. Instability of rotorbearing systems dr s k kakoty, professor, mechanical engineering, iit guwahati introduction rotor dynamics is the study of rotating machines and has a very important part to play throughout the modern industrial world. Introduction to dynamics of rotorbearing systems semantic scholar.
Introduction to rotordynamics mathias legrand mcgill university structural dynamics and vibration laboratory october 27, 2009. Introduction to dynamics of rotorbearing systems includes numerous examples, from a singledegreeoffreedom system to complicated industrial rotating machinery, which serve to illustrate fundamental dynamic behaviors. Active vibration control of a rotorbearing system based. Approximate evaluation for eigenvalues of rotorbearing systems. Under certain bearing or support conditions, the rotor response may be nonlinear. The process for simulating stock and flow modelsintegral calculusis described, with an example of a companys customer base. Dynamics of rotors and foundations e kramer 1993 3540557253 0387557253 springerverlag introduction to machinery analysis and monitoring js mitchell 1993 08781440 pennwell books vibration analysis of rotors cw lee 1993 0792323009 kluwer academic active magnetic bearings g schweitzer, h bleuler, a traxler 1994 37281220 vdf, eth.
Request pdf introduction to rotor dynamics rotordynamics studies the. The finite element equation of motion is formulated using the variational approach and the inclusion of axial torques gives rise to an incremental torsional stiffness matrix. Till today, the condition monitoring of rotorbearing systems based on vibrations. The basic equations for the modeling of linear rotorbearing systems are given along with an example for the rotordynamics of a multiple stag e compressor. Professional development program introduction to dynamics. This book is written as an introduction to rotor bearing dynamics for practicing engineers and students who are involved in rotordynamics and bearing design. Dynamics of a rigid rotor linearnonlinear bearings system subject to rotating unbalance and base excitations. Applied machinery dynamics company offers a range of innovative applied engineering solutions. Introduction rotor dynamics is specialized branch in which study includes the lateral and torsional vibration of rotating shaft. The goal of this book is to provide a stepbystep approach to the understanding of fundamentals of rotorbearing dynamics by using dyrobes. This study investigates the effect of constant axial torque on the dynamics of rotorbearing systems using a finite element model.
Introduction to pump rotordynamics rtoenavt143 9 3 2. The basic idea behind the workings of these programs was first put forth by holzer 1 as a way of finding natural frequencies of torsional systems. Introduction to dynamics of rotorbearing systems introduction to dynamics of rotorbearing systems wen jeng chen, edgar j. Dynamic effect of bearing wear on rotorbearing system. New of dynamics of rotorbearing systems using finite. Shape memory alloys applied to improve rotorbearing. Case study on dynamics of a turbopump instability in rotors a. Vibration analysis of a support excited rotor system with. A computer program is given for preparation of ball. In broad sense this area covers several categories namely modeling, analysis, identification and condition monitoring of rotor. An introduction to the influence of the bearings on the.
Introduction gears system is considered to be one of the most important power transmission systems and has a widely applications such as wind turbine, automobiles, aircrafts, marine vehicles and other industries. Introduction to dynamics of rotorbearing systems by wen jeng chen, 9781412051903, available at book depository with free delivery worldwide. The terms that are generally employed are rotor critical speed amplification factor ac and log decrement 0. Pdf introduction to dynamics of rotorbearing systems semantic. Tables 1 to 3 show the physical properties of the rotor, the compressor operating conditions current and desired, and a brief description of the bearings and seals in place. The dynamics of rotorbearing systems with axial torquea. Nonlinear dynamic analysis for high speed gearrotor. Introduction rotating machinery is commonly used in. Impeller seals, floating ring seals, thrust collars and balance pistons are a few of these elements.
The primary concerns in rotordynamic systems, including the critical speed. Introduction to turbomachinery rotating machinery master by uz duration. The key elements of system dynamicsstocks and flowsare explained. Dynamic analysis of rotorbearing systems using t hree. Shape memory alloys, rotorbearing systems, dynamics, experiments, hysteretic damping introduction shape memory alloys smas show a variety of remarkable characteristics, which is why they have been widely investigated in the last decades. Dynamic analysis, identification and control studies of. Dynamics of a rigid rotor linearnonlinear bearings system. Rotor dynamics meaning rotor dynamics definition rotor dy. Introduction to dynamics of rotorbearing systems 0. Rotor bearing solutions international is an engineering consulting services firm in charlottesville, virginia specializing in rotordynamics, bearing analysis, analysis active and passive magnetic bearing systems, and vibration analysis. Click download or read online button to get dynamics of rotating systems book now. The damping ratio term is not normally used in rotor dynamics. Summerssmitht this paper discusses the effect of the dynamic characteristics of bearing oil films on the lateral vibrational behaviour of rotating machines in a descriptive, nonmathematical way. Gunter introduction basic concepts singledegreeoffreedom systems free and forced vibrations free vibration forced vibration total motion coordinate systems and rotor motion coordinate systems steady state rotor motion elliptical motion.
Rotor dynamics detailed case history stepbystep rotorbearing system modeling, analysis, and problem solution by the introduction of rotor dynamics software and its application to a rotorbearing system bearing interaction with the rotating assembly, oilwhirlwhip phenomena, rotorbearing response, and stability illustrations. It is commonly used to analyze the behavior of structures ranging from jet engines and steam turbines to auto engines and computer disk storage. Introduction there are a number of special requirements connected with rotor dynamics that are peculiar to rotorbearing systems in the class of small turboshaft engines being developed for u. Effect of dynamic stiffness and damping coefficients of bearings and seals in rotors b. Dynamics of rotating systems download ebook pdf, epub. Techniques in dynamic rotorbearing systems analysis by lawrence joseph martin a thesis presented to the graduate committee of lehigh university in candidacy for the degree of master of science in mechanical engineering lehigh university 1976. The purpose of this book is to give a basic understanding of rotor dynamics phenomena with the help of simple rotor models and subsequently, the modern analysis methods for real life rotor systems. They have been used in civil engineering for seismic isolation janke et al. Techniques in dynamic rotorbearing systems analysis. Various sources of instability in rotors torsional vibration analysis a. The jeffcott rotor is first examined for stability under each of these excitation mechanisms. At its most basic level, rotor dynamics is concerned with one or more. A rotorbearing system is simulated in this study to investigate the effect of worn journal bearings on the system response and to specify the eventual development of additional frequency components.