The goal is to provide a stepbystep approach to the understanding of fundamentals of rotor. Field experience proves that the excessive vibration of the rotor of centrifugal pumps shows itself in wear and fatigue failure of shafts, bearings, wear rings, seals and impellers. Support global team on all steps of the rotorbearing systems design and dynamics analysis activities. Rotordynamic analysis is a crucial step in the development of rotor bearing systems. Nx nastran rotor dynamics applications the following is a list of common industryspecific problems that can be analyzed using the nx nastran rotor dynamics application. Rotor dynamic analysis of rm12 jet engine rotor using ansys deepak srikrishnanivas department of mechanical engineering blekinge institute of technology. Rotor dynamcis of a centrifugal pump technical university eindhoven, february 2006 5 2 whirl of simple rotors in rotor dynamics a common phenomenon is whirling. Combined blade element and momentum theories for non uniform inflow calculation.
This field is more than 140 year old and it is acquiring more attention day by day. Systematic modeling of rotor dynamics for small unmanned aerial vehicles limin wu, yijie ke and ben m. The possible cause is the change in the stiffness of the cracked rotor due to the concentration of strain energy in the vicinity of the crack. Solid model rotor dynamics is a method of performing the rotor dynamics analysis by solid elements instead of the conventional beam models. Timothy dimond, president, rotor bearing solutions international r bsi, formerly principal scientist of university of virginia rotating machinery and controls laboratory additional contributors. The rotating damping matrix, also depends upon the rotational velocities. Rotor dynamic analysis of rm12 jet engine rotor using ansys deepak srikrishnanivas department of mechanical engineering blekinge institute of technology karlskrona, sweden 2012 thesis submitted for completion of master of science in mechanical. Rotor dynamics software manual downloadrotor dynamics software manual. Kascak propulsion laboratory, avradcom research azd techuology laboratories lewis research cetzter clevelarzd, ohio national aeronautics and space administration scientific and technical information office 1980. Rotor dynamics by jaafar alsalaet department of mechanical engineering college of engineering university of basrah 1. The accurate prediction of dynamic characteristics, such as, critical speeds, natural whirl frequencies, instability thresholds and response to mass unbalance, is important in the design of any type of rotating machinery. Dynamic analysis of geared rotors by finite elements.
The basic component of rotor dynamics is shaft or rotor. Introduction to rotordynamics mathias legrand mcgill university structural dynamics and vibration laboratory october 27, 2009. You can change your consent settings at any time by unsubscribing or as. Pdf the lecture introduces the basic problems in the rotordynamics of turbomachinery, excessive vibration and instability.
Strong theoretical background in dynamics of rotating. Rotor dynamics software manual download rotor dynamics software manual. Rotor dynamics modeling programs mechanical acoustics. Dynamics of rotorbearing systems using finite elements. Rotor dynamics and finite element method is made use of, taking into consideration the continuous gyroscopic effect. It is the most valuable tool available for anyone working on modeling rotating machinery at the machine design stage or performing further analytical and experimental research on rotating machine dynamics. Pdf preliminary design of an axial turbine stage for a. Feb 16, 2017 rotor dynamics meaning rotor dynamics definition rotor dy.
Apply to engineer, intern, product designer and more. Fundamentals of rotorbearing dynamics and case histories in. A better understanding of rotor dynamics and support. The rotor bars are not insulated from the rotor core because they are made of metals having less resistance than the core. Direct integration of transient rotor dynamics albert f. Rotor dynamics is specialized branch in which study includes the lateral and torsional vibration of rotating shaft. Fundamentals of rotorbearing dynamics and case histories. Rotordynamics and finite element method is made use of, taking into consideration the continuous gyroscopic effect. Dynamics of rotors and foundations, erwin kramer, springerverlag berlin heidelberg 1993 vibration analysis of rotors, chongwon lee, center for noise and vibration control novic, korea, 1993, springer rotordynamics of automotive turbochargerslinear and nonlinear rotordynamics bearing design rotor. The primary purpose of the software is to illustrate features of rotating machines described in the.
The object of the analysis is to calculate the critical speeds of a rotor to find out if there are sufficient margins of separation between critical speed and the rotor operating speed. Finite element equations of transverse vibration of the spinning rocket is. Introduction to dynamics of rotor bearing systems includes numerous examples, from a singledegreeoffreedom system to complicated industrial rotating machinery, which serve to illustrate fundamental dynamic behaviors. 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. Introduction this software is a set of scripts written in matlab to accompany the above book. Dynamic analysis of geared rotors by finite elements ahmet kahraman, h. Rieger in the survey report will inform about existence of the new theory of a rotor dynamics and will consider and will assess the new inertial theory of a rotor dynamics. The concepts in the text are reinforced by parametric studies and numerous illustrative examples and figures.
Finite element equations of transverse vibration of. The industrial revolution began with reciprocating steam engines as devised by james watt in 1780, and the 19th century witnessed a rapid expansion in various industrial sectors. Rotor dynamic analysis of rm12 jet engine rotor using ansys. Turbocharger bearing support and rotor dynamics bearing support and dynamics of turbocharger rotors most of turbocharger tch rotors are supported in floatingring bearings fig. Chen unmanned systems research group department of electrical and computer engineering, faculty of engineering national university of singapore, 21 lower kent ridge rd, singapore 119077 abstract this paper proposes a systematic modeling ap. Figure 6 shows the typical situation when a compressor experienced instability. One neat thing about programs like adams and dads for that matter is that it it acausal in nature, unlike the blockbased environments simulink etc where you need to know how models interact when builind the model. Design audits of machineryrotor dynamics another reason rotor instability can lead to large vibrations is because the rotors natural frequency is excited. The rotorbearing system is modeled in exactly the same. Multispool dynamics simulation direct connection to bearing codes account for the flexibility of the supporting structure andor the disks connect directly to other ansys tools o the result. Again, we will have three different versions with increasing bearing stiffness, and we will assume our support bearings have equal stiffness in all radial directions. Rajiv tiwari,department of mechanical engineering,iit guwahati.
Optimization of the parameters of the tilting pad bearings and rotor to minimize the power loss at bearings the bearing loads are not equal different stiffness and damping coefficients are input for. Fundamentals of rotorbearing dynamics and case histories in the rotating machinery industry third annual short course dates. Therefore, in the product development process, there is no change in the stage at which it occurs. Each line represents the frequency spectrum at a particular rotor speed.
Lees cambridge university press, 2010 rotordynamics software manual 1. By using the upf create new elements for nonlinear rotor dynamics. So, modal analysis of a pump rotor is of great concern to researchers, international standard organizations and industries. Learn for free, pay a small fee for exam and get a certificate. Rotating shafts this type of a rotating structure can be analyzed using two cases the symmetric case and the unsymmetric case. Nonlinear coupling elementsbetween rotating and nonrotating parts oslide bearings oroller bearings osqueeze film dampers oseals ocontact model between rotating and nonrotating parts ocoupling by magnetic field oselflubricating bearing future. New of dynamics of rotorbearing systems using finite. Rotor dynamics analysis of a multistage centrifugal pump. The gyroscopic matrix, which depends on the rotational velocity or velocities of the analysis model.
Introduction and definitions rotor dynamics is the field of science that studies the response of rotating parts subjected to dynamic forces. Turbopump rotor dynamics because of high power density and low damping in rocket turbopumps, these machines exhibit in their most extreme form a variety of vibration effects, which are either absent or masked by normal damping mechanisms in other turbo machines. This book deals with rotordynamics of automotive turbochargers while encompassing the analysis of the dynamics of rotating machines at very high rotor speeds of 300,000 rpm and above. Rotordynamics is the preeminent guide to rotordynamic theory and practice. Army on rotor dynamics and bearing design for turboshaft engines used in helicopters. Rotating dynamics cylindrical modes since rotating machinery has to rotate to do useful work, lets consider what happens to the first mode of our rotor once it is spinning. Nptel, online courses and certification, learn for free. Nptel provides elearning through online web and video courses various streams. Free pdf download go to the directory where the file was downloaded and doubleclick the soavpu01580600us. A rotor dynamic model is developed by using finite element method fem, the rotor includes impellers, bearings and seals. It also includes disc and the bearings which supports the rotor. A machines overall reliablity depends heavily upon its underlying rotordynamic characteristics and their robustness.
It modifies the apparant stiffness of the model and can produce unstable. Rotor dynamics meaning rotor dynamics definition rotor dy. As a part of a project on microjet engine design and manufacture, this paper describes in detail all the phases required to preliminary design of a onestage axial turbine. These bearings are undemanding from manufacturing point of view and at the same time have. Table 3 shows the natural frequency for cracked and uncracked rotor system obtained through fem analysis. Mike swann, general manager, waukesha magnetic bearings 2. Mohanty,department of mechanical engineering,iit kharagpur. In any contem porary computer program based on the lund method, s will be assigned a numerical complex value for each iteration of the algorithm.
Rotordynamics software for predictive analyses of rotating. Rotordynamics of automotive turbochargers springerlink. Brno, czech republic technical support for rotordynamics ing. This book is written as an introduction to rotorbearing dynamics for practicing engineers and students who are involved in rotor dynamics and bearing designs. The utilization of finite element models in rotor dynamics has. Especially in machine and structural dynamics, we deal with the motion in. Therefore, dij will become a complex number, and the coefficients of the polynomial are lost. Computational techniques of rotor dynamics with the finite. Process description and product lifecycle stages solid model rotor dynamics is a method of performing the rotor dynamics analysis by solid elements instead of the conventional beam models.
We hope, that chair of the technical committee on rotor dynamics dr. Be the first to see new rotor dynamics engineer jobs. An improved method for calculating critical speeds and rotordynamics stability of turbomachinery by brian t. A better understanding of rotor dynamics and support stiffness if youre responsible for maintaining motors, you may have sent units off to be reconditioned, only to see them demonstrate high vibration levels once theyre back on the foundationand uncoupled to boot. Veldman strong interaction m1 viscous flow inviscid flow lecture notes in applied mathematics academic year 20112012. Therefore, rotordynamic analysis becomes a vital tool for.