Download or read book The Self Induced Oscillations of Rotors written by Mikhail Y. Kushul and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapid increase in operating speeds of mechanisms and machines during the last few decades has posed mechanical and technical engineers aseries of new problems. One of these is that of the investigation of the dynamics of flexible rotors operating at speeds greater than the first- and higher-order critical speeds. In con temporary machine design we must cope with various machines and assemblies containing shafts which operate under such conditions: turbogenerators. gas and steam turbines. spinning shafts. high-capacity pumps, and a multitude of special-purpose machines. One of the problems in the dynamics of flexible rotors-the passage through the resonance state-has re cently been almost completely solved in the work of Yu. A. Mitropol'skii. F. M. Dirnentberg, V. O. Kononenko. A. P. Fillippov. and others. Much less attention has been devoted to two other interrelated problems in the dynamics of high-speed rotors: the loss of stability in regime-combining forced vibrations due to imbalance in the supercritical region, along with self-induced or self-exc1ted vibrations. These problems are rapidly becoming more important as self-induced vibrations occurring at speeds beyond the critical speed are being met with more and more often in practice [1-3]. One of the main causes for the loss of stability of a rotor in the supercritical region. as was first estab lished by Kimball in [4] and Newkirk in [5] during the ninteen-twenties, is the force due to interna1 friction.
Download or read book The Self Induced Oscillations of Rotors written by Mikhail Y. Kushul and published by Springer. This book was released on 1997-01-14 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapid increase in operating speeds of mechanisms and machines during the last few decades has posed mechanical and technical engineers aseries of new problems. One of these is that of the investigation of the dynamics of flexible rotors operating at speeds greater than the first- and higher-order critical speeds. In con temporary machine design we must cope with various machines and assemblies containing shafts which operate under such conditions: turbogenerators. gas and steam turbines. spinning shafts. high-capacity pumps, and a multitude of special-purpose machines. One of the problems in the dynamics of flexible rotors-the passage through the resonance state-has re cently been almost completely solved in the work of Yu. A. Mitropol'skii. F. M. Dirnentberg, V. O. Kononenko. A. P. Fillippov. and others. Much less attention has been devoted to two other interrelated problems in the dynamics of high-speed rotors: the loss of stability in regime-combining forced vibrations due to imbalance in the supercritical region, along with self-induced or self-exc1ted vibrations. These problems are rapidly becoming more important as self-induced vibrations occurring at speeds beyond the critical speed are being met with more and more often in practice [1-3]. One of the main causes for the loss of stability of a rotor in the supercritical region. as was first estab lished by Kimball in [4] and Newkirk in [5] during the ninteen-twenties, is the force due to interna1 friction.
Download or read book Self Induced Oscillations of Rotors written by Mikhail Y Kushul and published by . This book was released on 1995-12-31 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Self Induced Oscillations of Rotors written by Mikhail Y. Kushulb and published by . This book was released on with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Linear and Nonlinear Rotordynamics written by Yukio Ishida and published by John Wiley & Sons. This book was released on 2013-03-05 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: A wide-ranging treatment of fundamental rotordynamics in order to serve engineers with the necessary knowledge to eliminate various vibration problems. New to this edition are three chapters on highly significant topics: Vibration Suppression - The chapter presents various methods and is a helpful guidance for professional engineers. Magnetic Bearings - The chapter provides fundamental knowledge and enables the reader to realize simple magnetic bearings in the laboratory. Some Practical Rotor Systems - The chapter explains various vibration characteristics of steam turbines and wind turbines. The contents of other chapters on Balancing, Vibrations due to Mechanical Elements, and Cracked Rotors are added to and revised extensively. The authors provide a classification of rotating shaft systems and general coverage of key ideas common to all branches of rotordynamics. They offers a unique analysis of dynamical problems, such as nonlinear rotordynamics, self-excited vibration, nonstationary vibration, and flow-induced oscillations. Nonlinear resonances are discussed in detail, as well as methods for shaft stability and various theoretical derivations and computational methods for analyzing rotors to determine and correct vibrations. This edition also includes case studies and problems.
Download or read book Theory of Self excited Mechanical Oscillations of Hinged Rotor Blades written by Robert P. Coleman and published by . This book was released on 1943 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vibrations of rotary-wing aircraft may derive their energy from the rotation of the rotor rather than from the air forces. A theoretical analysis of these vibrations is described and methods for its application are explained herein.
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 Dynamics of Rotors written by F. I. Niordson and published by Springer. This book was released on 1975-10 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Requirements on high efficiency of rotating machinery forces engineers to deal with problems of self-induced vi brations and balancing of rotors in a serious and scientific manner. The last decade has shown a leap towards the solution of advanced problems of this kind as indicated by the large amount of scientific and engineering papers on rotor dynamics published in international journals. In appreciation of this situation the General Assembly of the International Union of Theoretical and Applied Mecha nics (IUTAM) at its meeting in Moscow in 1972, acting on a proposal by the Danish Adhering Organization, decided to sponsor an international symposium on the "Dynamics of Rotors" . The scientific planning of the symposium was handed by a scientific committee, consisting of Prof. R.E.D. BISHOP, UK, Prof. S.H. CRANDALL, USA, Prof. F.M. DIMENTBERG, USSR, Dr. A. TONDL, CSSR, Prof. H. ZIEGLER, Switzerland and Prof. F.I. NIORDSON, Denmark, (Chairman). This committee was charged with the selection and invitation of a small number of outstanding scientists in the field, whose contributions to the symposium are presented in this volume. Participation was restricted to invited scientists and there were 87 active participants from 18 countries. Apart from a financial contribution from IUTAM to sup port travel and subsistence of invited participants, generous contributions were received from the following Danish Companies: Burmeister & Wain, Danfoss, The Danish Sugar corporation, DISA, Elsinore Shipbuilding Engineer, Kyndby v~rket, Niro Atomizer, and the Swedish Company STAL-LAVAL. The contributions are gratefully acknowledged.
Download or read book The Effect of Votex Shedding Induced Oscillations on a Savonius Rotor Current Meter in Situ written by Walter E. Schott and published by . This book was released on 1975 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanical Engineers Handbook written by Kent and published by . This book was released on 1915 with total page 1434 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Engineering written by and published by . This book was released on 1912 with total page 1078 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sensorless AC Electric Motor Control written by Alain Glumineau and published by Springer. This book was released on 2015-03-16 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph shows the reader how to avoid the burdens of sensor cost, reduced internal physical space, and system complexity in the control of AC motors. Many applications fields—electric vehicles, wind- and wave-energy converters and robotics, among them—will benefit. Sensorless AC Electric Motor Control describes the elimination of physical sensors and their replacement with observers, i.e., software sensors. Robustness is introduced to overcome problems associated with the unavoidable imperfection of knowledge of machine parameters—resistance, inertia, and so on—encountered in real systems. The details of a large number of speed- and/or position-sensorless ideas for different types of permanent-magnet synchronous motors and induction motors are presented along with several novel observer designs for electrical machines. Control strategies are developed using high-order, sliding-mode and quasi-continuous-sliding-mode techniques and two types of observer–controller schemes based on backstepping and sliding-mode techniques are described. Experimental results validate the performance of these observer and controller configurations with test trajectories of significance in difficult sensorless-AC-machine problems. Control engineers working with AC motors in a variety of industrial environments will find the space-and-cost-saving ideas detailed in Sensorless AC Electric Motor Control of much interest. Academic researchers and graduate students from electrical, mechanical and control-engineering backgrounds will be able to see how advanced theoretical control can be applied in meaningful real systems.
Download or read book Machine Science Abstracts written by and published by . This book was released on 1965 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Shock and Vibration Bulletin written by and published by . This book was released on 1987 with total page 664 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mechanical Sciences Abstracts written by and published by . This book was released on 1967 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Theory of Mechanical Oscillations of Rotors with Two Hinged Blades written by Arnold M. Feingold and published by . This book was released on 1943 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechanical stability of a rotor having two vertically hinged blades mounted upon symmetrical supports, that is, of equal stiffness and mass in all directions, is investigated and reported herein. The frequency equation is derived and shows the existence, in general, of two ranges of rotational speeds at which instability occurs. The lower region of instability is bounded by two shaft-critical speeds. At rotor speeds within this region, self-excited divergence of the rotor takes place analogous to the instability exhibited by a rotating shaft that is elliptical in cross section. Within the second instability range, the rotor system undergoes self-excited oscillations. Charts are presented giving the boundary points of both instability regions for a large variety of values of the physical parameters. The effect of damping is also included in the analysis.
Download or read book Soviet Machine Science written by and published by . This book was released on 1965 with total page 578 pages. Available in PDF, EPUB and Kindle. Book excerpt:
