Download or read book On the Theory of Acoustic Wave Scattering and Refraction by Internal Waves written by Peter Anthony Barakos and published by . This book was released on 1965 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: A theoretical treatment of the interaction between an acoustic plane wave and a stationary internal wave of a two-layer fluid is presented. The acoustic plane wave is incident from below upon a sinusoidal boundary separating two liquidhalf-spaces. The incident radiation undergoes reflection, scattering, and refraction at the interface. An integral method is employed to obtain two, exact, simultaneous infinite sets of equations relating the complex boundary amplitude coefficients. Exact expressions for the acoustic velocity potentials for the scattered and transmitted fields have also been found. From the general relations approximate equations have been developed for nine special cases. Two of these cases, important in underwater acoustics, are for small and large values of the product of the acoustic wavenumber and the internal wave amplitude. (Author).
Download or read book Acoustic Wave Scattering and Refraction by Internal Waves in a Model Tank written by Peter Anthony Barakos and published by . This book was released on 1968 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acoustic Wave Scattering from a Progressive Internal Wavefield written by P. A. Barakos and published by . This book was released on 1970 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: The scattering of sound from an internal wave field is considered. The acoustic index of refraction depends on the density of sea water. Hence, spatial and temporal density variations arising from the presence of internal waves will produce a perturbation in the index of refraction. Therefore, an acoustic wave transmitted through a stratitied fluid in which internal waves are present, will be modulated by the internal wave field and scattering and refraction will occur. It is shown that the frequency spectrum of the scattered acoustic field is comprised of the fundamental acoustic frequency and two side frequencies. Equations describing the phenomenon are given. (Author).
Download or read book Sound Propagation in the Sea written by Robert J. Urick and published by . This book was released on 1979 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Oceanography written by Defense Documentation Center (U.S.) and published by . This book was released on 1969 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamentals of Ocean Acoustics written by Leonid M. Brekhovskikh and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: As man turns his attention from the overcrowded continents of this planet and explores the spaciousness of the ocean, the applications of ocean acoustics become increasingly numerous and important. This book pro- vides an up-to-date introduction to the theory of sound propagation in the ocean, with much new material having been added throughout the second edition. It includes both ray and wave treatments and considerable attention is paid to stochastic problems such as the scattering of sound at rough surfaces and random inhomogeneties. An introductory chapter that discusses the basic experimental data complements the following theoretical chapters.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1987 with total page 1126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Fundamentals of Ocean Acoustics written by L. Brekhovskikh and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: The continents of our planet have already been exploited to a great extent. Therefore man is turning his sight to the vast spaciousness of the ocean whose resources - mineral, biological, energetic, and others - are just beginning to be used. The ocean is being intensively studied. Our notions about the dynam ics of ocean waters and their role in forming the Earth's climate as well as about the structure of the ocean bottom have substantially changed during the last two decades. An outstanding part in this accelerated exploration of the ocean is played by ocean acoustics. Only sound waves can propagate in water over large distances. Practically all kinds of telemetry, communication, location, and re mote sensing of water masses and the ocean bottom use sound waves. Propa gating over thousands of kilometers in the ocean, they bring information on earthquakes, eruptions of volcanoes, and distant storms. Projects using acoustical tomography systems for exploration of the ocean are presently be ing developed. Each of these systems will allow us to determine the three-di mensional structure of water masses in regions as large as millions of square kilometers.
Download or read book Fundamentals of Shallow Water Acoustics written by Boris Katsnelson and published by Springer Science & Business Media. This book was released on 2012-02-22 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shallow water acoustics (SWA), the study of how low and medium frequency sound propagates and scatters on the continental shelves of the worlds oceans, has both technical interest and a large number of practical applications. Technically, shallow water poses an interesting medium for the study of acoustic scattering, inverse theory, and propagation physics in a complicated oceanic waveguide. Practically, shallow water acoustics has interest for geophysical exploration, marine mammal studies, and naval applications. Additionally, one notes the very interdisciplinary nature of shallow water acoustics, including acoustical physics, physical oceanography, marine geology, and marine biology. In this specialized volume the authors, all of whom have extensive at-sea experience in US and Russian research efforts, have tried to summarize the main experimental, theoretical, and computational results in shallow water acoustics, with an emphasis on providing physical insight into the topics presented.
Download or read book Theory of Reflection of Electromagnetic and Particle Waves written by John Lekner and published by Springer Science & Business Media. This book was released on 2013-03-14 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is written for scientists and engineers whose work involves wave reflec tion or transmission. Most of the book is written in the language of electromagnetic theory, but, as the title suggests, many of the results can be applied to particle waves, specifically to those satisfying the Schr6dinger equation. The mathematical connection between electromagnetic s (or TE) waves and quantum particle waves is established in Chapter 1. The main results for s waves are translated into quantum mechanical language in the Appendix. There is also a close analogy between acoustic waves and electromagnetic p (or TM) waves, as shown in Section 1-4. Thus the book, though primarily intended for those working in optics, microwaves and radio, will be of use to physicists, chemists and electrical engineers studying reflection and transmission of particles at potential barriers. The tech niques developed here can also be used by those working in acoustics, ocean ography and seismology. Chapter 1 is recommended for all readers: it introduces reflection phenomena, defines the notation, and previews (in Section 1-6) the contents of the rest of the book. This preview will not be duplicated here. We note only that applied topics do appear: two examples are the important phenomenon of attenuated total reflection in Chapter 8, and the reflectivity of multilayer dielectric mirrors in Chapter 12. The subject matter is restricted to linear classical electrodynamics in non-magnetic media, and the corresponding particle analogues.
Download or read book Technical Abstract Bulletin written by and published by . This book was released on with total page 908 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wave Scattering from Statistically Rough Surfaces written by F. G. Bass and published by Elsevier. This book was released on 2013-10-22 with total page 541 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wave Scattering from Statistically Rough Surfaces discusses the complications in radio physics and hydro-acoustics in relation to wave transmission under settings seen in nature. Some of the topics that are covered include radar and sonar, the effect of variations in topographic relief or ocean waves on the transmission of radio and sound waves, the reproduction of radio waves from the lower layers of the ionosphere, and the oscillations of signals within the earth-ionosphere waveguide. The book begins with some fundamental idea of wave transmission theory and the theory of random processes as used to rough surfaces and to wave fields. This discussion is followed by an analysis of the average fields of sound and electromagnetic waves. A section on spatial correlation characteristics in the approximation of small perturbations is then given. Another chapter of the text explains the Kirchhoff method. The book will provide useful information to physicists, mechanical engineer, students, and researchers in the field of acoustics.
Download or read book Ocean Acoustics written by J.A. DeSanto and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Topics volume is devoted to a study of sound propagation in the ocean. The effect of the interior of the ocean on underwater sound is analogous to the effect of a lens on light. The oceanic lens is related, as in light propagation, to the index of refraction of the medium. The latter is giv~n by the ratio of the sound frequency to the speed of sound in water, typi ca lly about 1500 m s -1. It is the vari ation of the sound speed due to changing temperature, density, salinity, and pres sure in the complex ocean environment which creates the lens effect. Many oceanic processes such as currents, tides, eddies (circulating, translating regions of wa ter), and internal waves (the wave-like structure of the oceanic density variabil ity) contri bute in turn to the changes in sound speed'. The net effect of the ocean lens is to trap and guide sound waves in a channel created by the lens. The trapped sound can then propagate thousands of miles in this oceanic waveguide. In addition to the propagation in the interior of the ocean, sound can propagate into and back out of the ocean bottom as well as scatter from the ocean surface. Just as the sound produced by a loudspeaker in a room is affected by the walls of the room, so the ocean boundaries and the material properties below the ocean bottom are essential ingredients in the problem.
Download or read book Refraction and Scattering of Sound by a Shear Layer written by Robert H. Schlinker and published by . This book was released on 1980 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: The angle and amplitude changes for acoustic waves refracted by a circular open jet shear layer were determined. The generalized refraction theory was assessed experimentally for on axis and off axis acoustic source locations as source frequency varied from 1 kHz to 10 kHz and free stream Mach number varied from 0.1 to 0.4. Angle and amplitude changes across the shear layer show good agreement with theory. Experiments confirm that the refraction theory is independent of shear layer thickness, acoustic source frequency, and source type. A generalized theory is, thus, available for correcting far field noise data acquired in open jet test facilities. The effect of discrete tone scattering by the open jet turbulent shear layer was also studied. Scattering effects were investigated over the same Mach number range as frequency varied from 5 kHz to 15 kHz. Attenuation of discrete tone amplitude and tone broadening were measured as a function of acoustic source position and radiation angle. Scattering was found to be stronger at angles close to the open jet axis than at 90 deg, and becomes stronger as the acoustic source position shifts downstream. A scattering analysis provided an estimate of the onset of discrete tone scattering.
Download or read book Internal Waves in the Ocean written by and published by . This book was released on 1967 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NBS Special Publication written by and published by . This book was released on 1973 with total page 1562 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hydraulic Research in the United States and Canada written by and published by . This book was released on 1972 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt:
