Large-Eddy Simulation for Acoustics


Book Description

Noise around airports, trains, and industries attracts environmental concern and regulation. Large-eddy simulation (LES) is used for noise-reduced design and acoustical research. This 2007 book, by 30 experts, presents the theoretical background of acoustics and LES, and details about numerical methods, e.g. discretization schemes, boundary conditions, and coupling aspects.




Auralization


Book Description

This is the first focused and detailed textbook on acoustic virtual reality. Auralization is the creation of audible acoustic sceneries from computer-generated data. The term "auralization" is to be understood as being analogue to the well-known technique of "visualization". In visual illustration of scenes, data or any other meaningful information, in movie animation and in computer graphics, we describe the process of "making visible" as visualization. In acoustics, auralization is taking place when acoustic effects, primary sound signals or means of sound reinforcement or sound transmission, are processed to be presented by using electro-acoustic equipment. This book is organized as a comprehensive collection of basics, methodology and strategies of acoustic simulation and auralization.




Analytical System Dynamics


Book Description

"Analytical System Dynamics: Modeling and Simulation" combines results from analytical mechanics and system dynamics to develop an approach to modeling constrained multidiscipline dynamic systems. This combination yields a modeling technique based on the energy method of Lagrange, which in turn, results in a set of differential-algebraic equations that are suitable for numerical integration. Using the modeling approach presented in this book enables one to model and simulate systems as diverse as a six-link, closed-loop mechanism or a transistor power amplifier.




Acoustic Cavitation and Bubble Dynamics


Book Description

This brief explains in detail fundamental concepts in acoustic cavitation and bubble dynamics, and describes derivations of the fundamental equations of bubble dynamics in order to support those readers just beginning research in this field. Further, it provides an in-depth understanding of the physical basis of the phenomena. With regard to sonochemistry, the brief presents the results of numerical simulations of chemical reactions inside a bubble under ultrasound, especially for a single-bubble system and including unsolved problems. Written so as to be accessible both with and without prior knowledge of fundamental fluid dynamics, the brief offers a valuable resource for students and researchers alike, especially those who are unfamiliar with this field. A grasp of fundamental undergraduate mathematics such as partial derivative and fundamental integration is advantageous; however, even without any background in mathematics, readers can skip the equations and still understand the fundamental physics of the phenomena using the book’s wealth of illustrations and figures. As such, it is also suitable as an introduction to the field.




Bone Quantitative Ultrasound


Book Description

Many significant achievements in new ultrasound technologies to measure bone and models to elucidate the interaction and the propagation of ultrasonic waves in complex bone structures have been reported over the past ten years. Impaired bone remodeling affects not only the trabecular compartment but also the cortical one. Despite the crucial contribution of the cortical structure to the whole bone mechanical competence, cortical bone was understudied for a long time. A paradigm shift occurred around 2010, with a special focus placed on the importance of cortical bone. This has sparkled a great deal of interest in new ultrasound techniques to assess cortical bone. While our book ‘Bone Quantitative Ultrasound’ published in 2011 emphasized techniques to measure trabecular bone, this new book is devoted for a large part to the technologies introduced recently to measure cortical bone. These include resonant ultrasound spectroscopy, guided waves, scattering, and pulse-echo and tomography imaging techniques. Instrumentation, signal processing techniques and models used are detailed. Importantly, the data accumulated in recent years such as anisotropic stiffness, elastic engineering moduli, compression and shear wave speeds of cortical bones from various skeletal sites are presented comprehensively. A few chapters deal with the recent developments achieved in quantitative ultrasound of trabecular bone. These include (i) scattering-based approaches and their application to measure skeletal sites such as the spine and proximal femur and (ii) approaches exploiting the poro-elastic nature of bone. While bone fragility and osteoporosis are still the main motivation for developing bone QUS, this Book also includes chapters reporting ultrasound techniques developed for other applications of high interest such as 3-D imaging of the spine, assessment of implant stability and transcranial brain imaging. This book, together with the book ‘Bone Quantitative Ultrasound’ published in 2011 will provide a comprehensive overview of the methods and principles used in bone quantitative ultrasound and will be a benchmark for all novice or experienced researchers in the field. The book will offer recent experimental results and theoretical concepts developed so far and would be intended for researchers, graduate or undergraduate students, engineers, and clinicians who are involved in the field. The book should be considered as a complement to the first book publisher in 2011, rather than a second edition, in the sense that basic notions already presented in the first book are not repeated.




Formulas for Dynamics, Acoustics and Vibration


Book Description

With Over 60 tables, most with graphic illustration, and over 1000 formulas, Formulas for Dynamics, Acoustics, and Vibration will provide an invaluable time-saving source of concise solutions for mechanical, civil, nuclear, petrochemical and aerospace engineers and designers. Marine engineers and service engineers will also find it useful for diagnosing their machines that can slosh, rattle, whistle, vibrate, and crack under dynamic loads.




Structural Acoustics and Vibration


Book Description

Structural Acoustics and Vibration presents the modeling of vibrations of complex structures coupled with acoustic fluids in the low and medium frequency ranges. It is devoted to mechanical models, variationalformulations and discretization for calculating linear vibrations in the frequency domain of complex structures. The book includes theoretical formulations which are directly applicable to develop computer codes for the numerical simulation of complex systems, and gives a general scientific strategy to solve various complex structural acoustics problems in different areas such as spacecraft, aircraft, automobiles, and naval structures. The researcher may directly apply the material of the book to practical problems such as acoustic pollution, the comfort of passengers, and acoustic loads induced by propellers. Structural Acoustics and Vibration considers the mechanical and numerical aspects of the problem, and gives original solutions to the predictability of vibrations of complex structures interacting with internal and external, liquid and gaseous fluids. It is a self-contained general synthesis with a didactic presentation and fills the gap between analytical methods applied to simple geometries and statistical methods, which are useful in high frequency structural acoustic problems. Provides for the first time complex structures in scientific literature Presents a self-contained general synthesis with a didactic presentation Integrates the most advanced research topics on the subject Enables the researcher to solve complex structural acoustics problems in areas such as spacecraft, aircraft, automobiles, and naval structures Fills the gap between analytical methods applied to simple geometries and statistical methods Contains advanced mechanical and numerical modeling Provides appropriate formulations directly applicable for developing computer codes for the numerical simulation of complex systemssystems




Computational Simulation in Architectural and Environmental Acoustics


Book Description

This book reviews a variety of methods for wave-based acoustic simulation and recent applications to architectural and environmental acoustic problems. Following an introduction providing an overview of computational simulation of sound environment, the book is in two parts: four chapters on methods and four chapters on applications. The first part explains the fundamentals and advanced techniques for three popular methods, namely, the finite-difference time-domain method, the finite element method, and the boundary element method, as well as alternative time-domain methods. The second part demonstrates various applications to room acoustics simulation, noise propagation simulation, acoustic property simulation for building components, and auralization. This book is a valuable reference that covers the state of the art in computational simulation for architectural and environmental acoustics.




Underwater Acoustic Modeling and Simulation


Book Description

Underwater Acoustic Modeling and Simulation, Fourth Edition continues to provide the most authoritative overview of currently available propagation, noise, reverberation, and sonar-performance models. This fourth edition of a bestseller discusses the fundamental processes involved in simulating the performance of underwater acoustic systems and emphasizes the importance of applying the proper modeling resources to simulate the behavior of sound in virtual ocean environments. New to the Fourth Edition Extensive new material that addresses recent advances in inverse techniques and marine-mammal protection Problem sets in each chapter Updated and expanded inventories of available models Designed for readers with an understanding of underwater acoustics but who are unfamiliar with the various aspects of modeling, the book includes sufficient mathematical derivations to demonstrate model formulations and provides guidelines for selecting and using the models. Examples of each type of model illustrate model formulations, model assumptions, and algorithm efficiency. Simulation case studies are also included to demonstrate practical applications. Providing a thorough source of information on modeling resources, this book examines the translation of our physical understanding of sound in the sea into mathematical models that simulate acoustic propagation, noise, and reverberation in the ocean. The text shows how these models are used to predict and diagnose the performance of complex sonar systems operating in the undersea environment.




Proceedings of 2nd International Conference on Fluid Dynamics & Aerodynamics 2017


Book Description

October 19-20, 2017 Rome, Italy key Topics : Fluid Dynamics, Numerical Methods, CFD Methodology, Geophysical Fluid Dynamics, Heat Transfer System, Aerodynamics, Aero-acoustics, Magneto Hydrodynamics, Aerodynamics Simulations, Biofluid Mechanics, Thermo-Fluid Dynamics, Micro Fluidics,