Sound Propagation In Stratified Fluids

Author : Calvin H. Wilcox
Publisher : Springer Science & Business Media
Page : 206 pages
File Size : 49,5 Mb
Release : 2012-12-06
Category : Technology & Engineering
ISBN : 9781461211242

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Sound Propagation in Stratified Fluids by Calvin H. Wilcox Pdf

Stratified fluids whose densities, sound speeds and other parameters are functions of a single depth coordinate occur widely in nature. Indeed, the earth's gravitational field imposes a stratification on its atmosphere, oceans and lakes. It is well known that their stratification has a profound effect on the propagation of sound in these fluids. The most striking effect is probably the occurrence of acoustic ducts, due to minima of the sound speed, that can trap sound waves and cause them to propagate hori zontally. The reflection, transmission and distortion of sonar signals by acoustic ducts is important in interpreting sonar echoes. Signal scattering by layers of microscopic marine organisms is important to both sonar engi neers and marine biologists. Again, reflection of signals from bottom sediment layers overlying a penetrable bottom are of interest both as sources of unwanted echoes and in the acoustic probing of such layers. Many other examples could be given. The purpose of this monograph is to develop from first principles a theory of sound propagation in stratified fluids whose densities and sound speeds are essentially arbitrary functions of the depth. In physical terms, the propagation of both time-harmonic and transient fields is analyzed. The corresponding mathematical model leads to the study of boundary value problems for a scalar wave equation whose coefficients contain the pre scribed density and sound speed functions.

Author : Jiajun Zhao
Publisher : Springer
Page : 72 pages
File Size : 40,7 Mb
Release : 2016-08-06
Category : Technology & Engineering
ISBN : 9789811021251

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Manipulation of Sound Properties by Acoustic Metasurface and Metastructure by Jiajun Zhao Pdf

This thesis focuses on the manipulation of sound properties by artificial materials. It elaborates on the fundamental design of acoustic metasurfaces and metastructures as the extension of metamaterials, and their functionality in the manipulation of sound properties. A broad and comprehensive guideline of designing acoustic metasurfaces and metastructures is also provided. Based on the proposed subwavelength metasurfaces and the metastructures with a simplified layout, multiple potential applications are demonstrated. This thesis will appeal to acoustic engineers and researchers who are interested in designing acoustic artificial structures.

Author : Anonim
Publisher : Unknown
Page : 208 pages
File Size : 43,6 Mb
Release : 1980
Category : Science
ISBN : CORNELL:31924057177747

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Technical Abstract Bulletin by Anonim Pdf

Author : Anonim
Publisher : Unknown
Page : 572 pages
File Size : 49,7 Mb
Release : 1991-04
Category : Aeronautics
ISBN : UFL:31262082071548

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Scientific and Technical Aerospace Reports by Anonim Pdf

Author : Sir M. J. Lighthill,James Lighthill
Publisher : Cambridge University Press
Page : 528 pages
File Size : 40,8 Mb
Release : 2001-11-15
Category : Mathematics
ISBN : 0521010454

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Waves in Fluids by Sir M. J. Lighthill,James Lighthill Pdf

A comprehensive textbook in which the author describes the science of waves in liquids and gases. Drawing on a subject of enormous extent and variety, he provides his readers with a thorough analysis of the most important and representative types of waves including sound waves, shock waves, waterwaves of all kinds, and the so-called internal waves (inside atmospheres and oceans) due to intensity stratification. Emphasis throughout is on the most generally useful fundamental ideas of wave science, including the principles of how waves interact with flows. This standard work on one of the great subdivisions of the dynamics of fluids is lucidly written and will be invaluable to engineers, physicists, geophysicists, applied mathematicians or any research worker concerned with wave motions or fluid fllows. It is especially suitable as a textbook for courses at the final year undergraduate or graduate level.

Author : Robert Thomas Beyer
Publisher : Van Nostrand Reinhold Company
Page : 408 pages
File Size : 54,8 Mb
Release : 1984
Category : Fluids
ISBN : UCAL:B4532797

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Nonlinear Acoustics in Fluids by Robert Thomas Beyer Pdf

New York : Van Nostrand Reinhold, c1984.

Author : Huijun Yang
Publisher : Springer Science & Business Media
Page : 253 pages
File Size : 48,9 Mb
Release : 2013-06-29
Category : Science
ISBN : 9781475743814

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Wave Packets and Their Bifurcations in Geophysical Fluid Dynamics by Huijun Yang Pdf

The material in this book is based predominantly on my recent work. It is the first monograph on the subject, though some support material may overlap other monographs. The investigation of wave packets and their bi furcations is very interesting, and useful theoretically and in practice, not only in geophysical fluid dynamics, which is the field to which the theory is being applied here, but also in other fields in mathematics and the natural sciences. I hope that the applied mathematician will find reading this book worthwhile, especially the material on the behavior of highly nonlinear dy namic systems. However, it is my belief that applying the concepts and methods developed here to other fields will be both interesting and con structive, since there are numerous phenomena in other areas of physics that share the characteristics of those in geophysical fluid dynamics. The theory developed here provides an effective tool to investigate the structure and the structural changes of dynamic systems in physics. Applications of the theory in geophysical fluid dynamics are an example of its usefulness and effectiveness. Some of the results presented here give us more insight into the nature of geophysical fluids. Moreover, the material is presented systematically and developmentally. Necessary basic knowledge is provided to make the book more readable for graduate students and researchers in such fields as applied mathematics, geophysical fluid dynamics, atmospheric sciences, and physical oceanogra phy.

Author : Eduard Feireisl,Antonín Novotný
Publisher : Birkhäuser
Page : 524 pages
File Size : 49,7 Mb
Release : 2017-11-24
Category : Mathematics
ISBN : 9783319637815

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Singular Limits in Thermodynamics of Viscous Fluids by Eduard Feireisl,Antonín Novotný Pdf

This book is about singular limits of systems of partial differential equations governing the motion of thermally conducting compressible viscous fluids. "The main aim is to provide mathematically rigorous arguments how to get from the compressible Navier-Stokes-Fourier system several less complex systems of partial differential equations used e.g. in meteorology or astrophysics. However, the book contains also a detailed introduction to the modelling in mechanics and thermodynamics of fluids from the viewpoint of continuum physics. The book is very interesting and important. It can be recommended not only to specialists in the field, but it can also be used for doctoral students and young researches who want to start to work in the mathematical theory of compressible fluids and their asymptotic limits." Milan Pokorný (zbMATH) "This book is of the highest quality from every point of view. It presents, in a unified way, recent research material of fundament al importance. It is self-contained, thanks to Chapter 3 (existence theory) and to the appendices. It is extremely well organized, and very well written. It is a landmark for researchers in mathematical fluid dynamics, especially those interested in the physical meaning of the equations and statements." Denis Serre (MathSciNet)

Author : Donald A. Drew,Stephen L. Passman
Publisher : Springer Science & Business Media
Page : 311 pages
File Size : 47,8 Mb
Release : 2006-05-10
Category : Mathematics
ISBN : 9780387226378

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Theory of Multicomponent Fluids by Donald A. Drew,Stephen L. Passman Pdf

An exposition of the derivation and use of equations of motion for two-phase flow. The approach taken derives the equations of motion using ensemble averaging, and compares them with those derived from control volume methods. Closure for dispersed flows is discussed, and some fundamental solutions are given. The work focuses on the fundamental aspects of two-phase flow, and is intended to give the reader a background for understanding the dynamics as well as a system of equations that can be used in predictions of the behavior of dispersed two-phase flows. The exposition in terms of ensemble averaging is new, and combining it with modern continuum mechanics concepts makes this book unique. Intended for engineering, mathematics and physics researchers and advanced graduate students working in the field.

Author : Carlo Marchioro,Mario Pulvirenti
Publisher : Springer Science & Business Media
Page : 295 pages
File Size : 41,8 Mb
Release : 2012-12-06
Category : Mathematics
ISBN : 9781461242840

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Mathematical Theory of Incompressible Nonviscous Fluids by Carlo Marchioro,Mario Pulvirenti Pdf

Fluid dynamics is an ancient science incredibly alive today. Modern technol ogy and new needs require a deeper knowledge of the behavior of real fluids, and new discoveries or steps forward pose, quite often, challenging and diffi cult new mathematical {::oblems. In this framework, a special role is played by incompressible nonviscous (sometimes called perfect) flows. This is a mathematical model consisting essentially of an evolution equation (the Euler equation) for the velocity field of fluids. Such an equation, which is nothing other than the Newton laws plus some additional structural hypo theses, was discovered by Euler in 1755, and although it is more than two centuries old, many fundamental questions concerning its solutions are still open. In particular, it is not known whether the solutions, for reasonably general initial conditions, develop singularities in a finite time, and very little is known about the long-term behavior of smooth solutions. These and other basic problems are still open, and this is one of the reasons why the mathe matical theory of perfect flows is far from being completed. Incompressible flows have been attached, by many distinguished mathe maticians, with a large variety of mathematical techniques so that, today, this field constitutes a very rich and stimulating part of applied mathematics.

Author : Jean-Claude Nedelec
Publisher : Springer Science & Business Media
Page : 356 pages
File Size : 45,8 Mb
Release : 2001-03-30
Category : Computers
ISBN : 0387951555

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Acoustic and Electromagnetic Equations by Jean-Claude Nedelec Pdf

Acoustic and electromagnetic waves underlie a range of modern technology from sonar, radio, and television to microwave heating and electromagnetic compatibility analysis. This book, written by an international researcher, presents some of the research in a complete way. It is useful for graduate students in mathematics, physics, and engineering.

Author : Frank Ihlenburg
Publisher : Springer Science & Business Media
Page : 226 pages
File Size : 49,7 Mb
Release : 2006-05-02
Category : Mathematics
ISBN : 9780387227009

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Finite Element Analysis of Acoustic Scattering by Frank Ihlenburg Pdf

A cognitive journey towards the reliable simulation of scattering problems using finite element methods, with the pre-asymptotic analysis of Galerkin FEM for the Helmholtz equation with moderate and large wave number forming the core of this book. Starting from the basic physical assumptions, the author methodically develops both the strong and weak forms of the governing equations, while the main chapter on finite element analysis is preceded by a systematic treatment of Galerkin methods for indefinite sesquilinear forms. In the final chapter, three dimensional computational simulations are presented and compared with experimental data. The author also includes broad reference material on numerical methods for the Helmholtz equation in unbounded domains, including Dirichlet-to-Neumann methods, absorbing boundary conditions, infinite elements and the perfectly matched layer. A self-contained and easily readable work.

Author : Andrzej Lasota,Michael C. Mackey
Publisher : Springer Science & Business Media
Page : 481 pages
File Size : 50,6 Mb
Release : 2013-11-27
Category : Mathematics
ISBN : 9781461242864

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Chaos, Fractals, and Noise by Andrzej Lasota,Michael C. Mackey Pdf

The first edition of this book was originally published in 1985 under the ti tle "Probabilistic Properties of Deterministic Systems. " In the intervening years, interest in so-called "chaotic" systems has continued unabated but with a more thoughtful and sober eye toward applications, as befits a ma turing field. This interest in the serious usage of the concepts and techniques of nonlinear dynamics by applied scientists has probably been spurred more by the availability of inexpensive computers than by any other factor. Thus, computer experiments have been prominent, suggesting the wealth of phe nomena that may be resident in nonlinear systems. In particular, they allow one to observe the interdependence between the deterministic and probabilistic properties of these systems such as the existence of invariant measures and densities, statistical stability and periodicity, the influence of stochastic perturbations, the formation of attractors, and many others. The aim of the book, and especially of this second edition, is to present recent theoretical methods which allow one to study these effects. We have taken the opportunity in this second edition to not only correct the errors of the first edition, but also to add substantially new material in five sections and a new chapter.

Author : Daniel D. Joseph
Publisher : Springer Science & Business Media
Page : 772 pages
File Size : 45,7 Mb
Release : 2013-11-27
Category : Science
ISBN : 9781461244622

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Fluid Dynamics of Viscoelastic Liquids by Daniel D. Joseph Pdf

This book is about two special topics in rheological fluid mechanics: the elasticity of liquids and asymptotic theories of constitutive models. The major emphasis of the book is on the mathematical and physical consequences of the elasticity of liquids; seventeen of twenty chapters are devoted to this. Constitutive models which are instantaneously elastic can lead to some hyperbolicity in the dynamics of flow, waves of vorticity into rest (known as shear waves), to shock waves of vorticity or velocity, to steady flows of transonic type or to short wave instabilities which lead to ill-posed problems. Other kinds of models, with small Newtonian viscosities, give rise to perturbed instantaneous elasticity, associated with smoothing of discontinuities as in gas dynamics. There is no doubt that liquids will respond like elastic solids to impulses which are very rapid compared to the time it takes for the molecular order associated with short range forces in the liquid, to relax. After this, all liquids look viscous with signals propagating by diffusion rather than by waves. For small molecules this time of relaxation is estimated as lQ-13 to 10-10 seconds depending on the fluids. Waves associated with such liquids move with speeds of 1 QS cm/s, or even faster. For engineering applications the instantaneous elasticity of these fluids is of little interest; the practical dynamics is governed by diffusion, ·say, by the Navier-Stokes equations. On the other hand, there are other liquids which are known to have much longer times of relaxation.

Author : David Colton,Rainer Kress
Publisher : Springer Science & Business Media
Page : 347 pages
File Size : 46,5 Mb
Release : 2013-03-09
Category : Science
ISBN : 9783662035375

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Inverse Acoustic and Electromagnetic Scattering Theory by David Colton,Rainer Kress Pdf

This book is devoted to the mathematical and numerical analysis of the inverse scattering problem for acoustic and electromagnetic waves. The second edition includes material on Newton’s method for the inverse obstacle problem, an elegant proof of uniqueness for the inverse medium problem, a discussion of the spectral theory of the far field operator and a method for determining the support of an inhomogeneous medium from far field data.