Vibration Theory and Applications with Finite Elements and Active Vibration Control

An advanced look at vibration analysis with a focus on active vibration suppression As modern devices, from cell phones to airplanes, become lighter and more flexible, vibration suppression and analysis becomes more critical. Vibration with Control, 2nd Edition includes modelling, analysis and testing methods. New topics include metastructures and the use of piezoelectric materials, and numerical methods are also discussed. All material is placed on a firm mathematical footing by introducing concepts from linear algebra (matrix theory) and applied functional analysis when required. Key features: Combines vibration modelling and analysis with active control to provide concepts for effective vibration suppression. Introduces the use of piezoelectric materials for vibration sensing and suppression. Provides a unique blend of practical and theoretical developments. Examines nonlinear as well as linear vibration analysis. Provides Matlab instructions for solving problems. Contains examples and problems. PowerPoint Presentation materials and digital solutions manual available for instructors. Vibration with Control, 2nd Edition is an ideal reference and textbook for graduate students in mechanical, aerospace and structural engineering, as well as researchers and practitioners in the field.

Introduces the theory and applications of the extended finite element method (XFEM) in the linear and nonlinear problems of continua, structures and geomechanics Explores the concept of partition of unity, various enrichment functions, and fundamentals of XFEM formulation. Covers numerous applications of XFEM including fracture mechanics, large deformation, plasticity, multiphase flow, hydraulic fracturing and contact problems Accompanied by a website hosting source code and examples

A comprehensive and versatile treatment of an important and complex topic in vehicle design Written by an expert in the field with over 30 years of NVH experience, Noise and Vibration Control of Automotive Body offers nine informative chapters on all of the core knowledge required for noise, vibration, and harshness engineers to do their job properly. It starts with an introduction to noise and vibration problems; transfer of structural-borne noise and airborne noise to interior body; key techniques for body noise and vibration control; and noise and vibration control during vehicle development. The book then goes on to cover all the noise and vibration issues relating to the automotive body, including: overall body structure; local body structure; sound package; excitations exerted on the body and transfer functions; wind noise; body sound quality; body squeak and rattle; and the vehicle development process for an automotive body. Vehicle noise and vibration is one of the most important attributes for modern vehicles, and it is extremely important to understand and solve NVH problems. Noise and Vibration Control of Automotive Body offers comprehensive coverage of automotive body noise and vibration analysis and control, making it an excellent guide for body design engineers and testing engineers. Covers all the noise and vibration issues relating to the automotive body Features a thorough set of tables, illustrations, photographs, and examples Introduces automotive body structure and noise and vibration problems Pulls together the diverse topics of body structure, sound package, sound quality, squeak and rattle, and target setting Noise and Vibration Control of Automotive Body is a valuable reference for engineers, designers, researchers, and graduate students in the fields of automotive body design and NVH.

Researchers have studied many methods of using active and passive control devices for absorbing vibratory energy. Active devices, while providing significant reductions in structural motion, typically require large (and often multiply-redundant) power sources, and thereby raise concerns about stability. Passive devices are fixed and cannot be modified based on information of excitation or structural response. Semiactive devices on the other hand can provide significant vibration reductions comparable to those of active devices but with substantially reduced power requirements and in a stable manner. Technology of Semiactive Devices and Applications in Vibration Mitigation presents the most up-to-date research into semiactive control systems and illustrates case studies showing their implementation and effectiveness in mitigating vibration. The material is presented in a way that people not familiar with control or structural dynamics can easily understand. Connecting structural dynamics with control, this book: Provides a history of semiactive control and a bibliographic review of the most common semiactive control strategies. Presents state-of-the-art semiactive control systems and illustrates several case studies showing their implementation and effectiveness to mitigate vibration. Illustrates applications related to noise attenuation, wind vibration damping and earthquake effects mitigation amongst others. Offers a detailed comparison between collocated and non-collocated systems. Formulates the design concepts and control algorithms in simple and readable language. Includes an appendix that contains critical considerations about semiactive devices and methods of evaluation of the original damping of a structure. Technology of Semiactive Devices and Applications in Vibration Mitigation is a must-have resource for researchers, practitioners and design engineers working in civil, automotive and mechanical engineering. In addition it is undoubtedly the key reference for all postgraduate students studying in the field.

Presents new developments on machine tool vibration control based on discontinuous dynamical systems Machining instability is a topical area, and there are a wide range of publications that cover the topic. However, many of these previous studies have started by assuming that the behavior of the system can be linearised. Meanwhile, there are many recent advances in the fields of signal processing, nonlinear dynamics, and nonlinear control, all of which are relevant to the machining stability problem. This book establishes the fundamentals of cutting mechanics and machine tool dynamics in the simultaneous time-frequency domain. The new nonlinear control theory developed by the authors that facilitates simultaneous control of vibration amplitude in the time-domain and spectral response in the frequency-domain provides the foundation for the development of a controller architecture universally viable for the control of dynamic instability including bifurcation and chaos. Once parameters underlying the coupling, interaction, and evolution of different cutting states and between the tool and workpiece are established, they can then be incorporated into the architecture to create a control methodology that mitigate machining instability and enable robust, chatter-free machine tool design applicable in particular to high speed micro- and nano-machining. Presents new developments on machine tool vibration control based on discontinuous dynamical systems Provides a clear and concise approach to the understanding and control of machine tool and workpiece vibrations from an alternative view, contributing to an in-depth understanding of cutting dynamics and robust control of machining instability Equips the reader with the knowledge to understand the dynamics of cutting and operation of machine-tool systems in different conditions as well as the concept of cutting instability control Includes data examples in MATLAB coding

Everything engineers need to know about mechanical vibration and shock…in one authoritative reference work! This fully updated and revised 3rd edition addresses the entire field of mechanical vibration and shock as one of the most important types of load and stress applied to structures, machines and components in the real world. Examples include everything from the regular and predictable loads applied to turbines, motors or helicopters by the spinning of their constituent parts to the ability of buildings to withstand damage from wind loads or explosions, and the need for cars to maintain structural integrity in the event of a crash. There are detailed examinations of underlying theory, models developed for specific applications, performance of materials under test conditions and in real-world settings, and case studies and discussions of how the relationships between these affect design for actual products. Invaluable to engineers specializing in mechanical, aeronautical, civil, electrical and transportation engineering, this reference work, in five volumes is a crucial resource for the solution of shock and vibration problems. The relative and absolute response of a mechanical system with a single degree of freedom is considered for an arbitrary excitation, and its transfer function is defined in various forms. The characteristics of sinusoidal vibration are examined in the context both of the real world and of laboratory tests, and for both transient and steady state response of the one-degree-of-freedom system. Viscous damping and then non-linear damping are considered. The various types of swept sine perturbations and their properties are described and, for the one-degree-of-freedom system, the consequence of an inappropriate choice of sweep rate are considered. From the latter, rules governing the choice of suitable sweep rates are then developed.

An in-depth analysis of machine vibration in rotating machinery Whether it's a compressor on an offshore platform, a turbocharger in a truck or automobile, or a turbine in a jet airplane, rotating machinery is the driving force behind almost anything that produces or uses energy. Counted on daily to perform any number of vital societal tasks, turbomachinery uses high rotational speeds to produce amazing amounts of power efficiently. The key to increasing its longevity, efficiency, and reliability lies in the examination of rotor vibration and bearing dynamics, a field called rotordynamics. A valuable textbook for beginners as well as a handy reference for experts, Machinery Vibration and Rotordynamics is teeming with rich technical detail and real-world examples geared toward the study of machine vibration. A logical progression of information covers essential fundamentals, in-depth case studies, and the latest analytical tools used for predicting and preventing damage in rotating machinery. Machinery Vibration and Rotordynamics: Combines rotordynamics with the applications of machinery vibration in a single volume Includes case studies of vibration problems in several different types of machines as well as computer simulation models used in industry Contains fundamental physical phenomena, mathematical and computational aspects, practical hardware considerations, troubleshooting, and instrumentation and measurement techniques For students interested in entering this highly specialized field of study, as well as professionals seeking to expand their knowledge base, Machinery Vibration and Rotordynamics will serve as the one book they will come to rely upon consistently.

Without doubt the best modern and up-to-date text on the topic, wirtten by one of the world leading experts in the field. Should be on the desk of any practitioner or researcher involved in the field of Machine Condition Monitoring Simon Braun, Israel Institute of Technology Explaining complex ideas in an easy to understand way, Vibration-based Condition Monitoring provides a comprehensive survey of the application of vibration analysis to the condition monitoring of machines. Reflecting the natural progression of these systems by presenting the fundamental material and then moving onto detection, diagnosis and prognosis, Randall presents classic and state-of-the-art research results that cover vibration signals from rotating and reciprocating machines; basic signal processing techniques; fault detection; diagnostic techniques, and prognostics. Developed out of notes for a course in machine condition monitoring given by Robert Bond Randall over ten years at the University of New South Wales, Vibration-based Condition Monitoring: Industrial, Aerospace and Automotive Applications is essential reading for graduate and postgraduate students/ researchers in machine condition monitoring and diagnostics as well as condition monitoring practitioners and machine manufacturers who want to include a machine monitoring service with their product. Includes a number of exercises for each chapter, many based on Matlab, to illustrate basic points as well as to facilitate the use of the book as a textbook for courses in the topic. Accompanied by a website www.wiley.com/go/randall housing exercises along with data sets and implementation code in Matlab for some of the methods as well as other pedagogical aids. Authored by an internationally recognised authority in the area of condition monitoring.

The vast majority of vibrations encountered in the real environment are random in nature. Such vibrations are intrinsically complicated and this volume describes the process that enables us to simplify the required analysis, along with the analysis of the signal in the frequency domain. The power spectrum density is also defined, together with the requisite precautions to be taken in its calculations as well as the processes (windowing, overlapping) necessary to obtain improved results. An additional complementary method – the analysis of statistical properties of the time signal – is also described. This enables the distribution law of the maxima of a random Gaussian signal to be determined and simplifies the calculation of fatigue damage by avoiding direct peak counting.