Download or read book Radiation Refraction and Scattering of Acoustic Waves in a Shear Flow written by Saebastien Candel and published by . This book was released on 1976 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 NASA Technical Paper written by and published by . This book was released on 1981 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeroacoustic Measurements written by Thomas J. Mueller and published by Springer Science & Business Media. This book was released on 2013-11-27 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book describes recent developments in aeroacoustic measurements in wind tunnels and the interpretation of the resulting data. The reader will find the latest measurement techniques described along with examples of the results.
Download or read book Recent Advances in Aeroacoustics written by A. Krothapalli and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Joint Institute for Aeronautics and Acoustics at Stanford University was established in October 1973 to provide an academic environment for long-term cooperative research between Stanford and NASA Ames Research Center. Since its establishment, the Institute has conducted theoretical and experimental work in the areas of aerodynamics, acoustics, fluid mechanics, flight dynamics, guidance and control, and human factors. This research has involved Stanford faculty, research associates, graduate students, and many distinguished visitors in collaborative efforts with the research staff of NASA Ames Research Center. The occasion of the Institute's tenth anniversary was used to reflect back on where that research has brought us, and to consider where our endeavors should be directed next. Thus, an International Symposium was held to review recent advances in the fields relevant to the activities of the Institute and to discuss the areas of research to be undertaken in the future. This anniversary was also chosen as an opportunity to honor one of the Institute's founders and its director, Professor Krishnamurty Karamcheti. It has been his crea tive inspiration that has provided the ideal research environment at the Joint Institute.
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 AIAA 76 531 AIAA 76 589 With omissions in numbering written by and published by . This book was released on 1976 with total page 754 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scattering of Acoustic and Elastic Waves by Surfaces of Arbitrary Shape written by Robert Peter Banaugh and published by . This book was released on 1962 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AIAA 6th Aeroacoustics Conference written by and published by . This book was released on 1980 with total page 708 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Underwater Scattering and Radiation written by Allan D. Pierce and published by Academic Press. This book was released on 2013-10-22 with total page 395 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater Scattering and Radiation describes the relevant theoretical foundations of underwater scattering and radiation. Acoustic scattering from elastic solids is discussed, and variational formulations in acoustic radiation and scattering are presented. Surface waves and quasi-cylindrical modes are also explored, along with the Helmholtz-Kirchhoff integral corollaries. Comprised of two chapters, this volume begins with a comprehensive account of scattering by elastic objects, focusing on the classic idealized shapes of spheres and infinite cylinders. The reader is introduced to important concepts such as normal modes, the S-matrix, and the T-matrix as well as resonances, whispering gallery modes, Franz modes, and Stoneley waves. Subsequent sections describe methods for treating scattering by elastic bodies of more general shapes. The T-matrix formalism is discussed and then applied to spheroidal scatterers and finite cylinders. The second chapter analyzes how variational principles can be used in acoustics, with the choice of topics directed toward applications to underwater acoustic radiation and scattering. This book will be of interest to physicists.
Download or read book Selected Library Acquisitions written by United States. Department of Transportation and published by . This book was released on with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High Frequency and Pulse Scattering written by Allan D. Pierce and published by Academic Press. This book was released on 2013-10-22 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: High Frequency and Pulse Scattering investigates high frequency and pulse scattering, with emphasis on the phenomenon of echoes from objects. Geometrical and catastrophe optics methods in scattering are discussed, along with the scattering of sound pulses and the ringing of target resonances. Caustics and associated diffraction catastrophes are also examined. Comprised of two chapters, this volume begins with a detailed account of geometrically based approximation methods in scattering theory, focusing on waves transmitted through fluid and elastic scatterers and glory scattering; surface ray representations of scattering by shells and other smooth objects; and caustics and associated diffraction catastrophes. The second chapter deals with the relation between sound pulses and the vibrational spectra of elastic submerged objects. The theory of the scattering of sound pulses from elastic and impenetrable objects is described, together with the theory of surface wave pulses. Target resonances and the singularity expansion method are also analyzed. This book will be of interest to physicists.
Download or read book AIAA 8th Aeroacoustics Conference written by and published by . This book was released on 1983 with total page 746 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AIAA 79 0570 AIAA 79 0629 written by and published by . This book was released on 1979 with total page 638 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1972 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reflection and Transmission of Acoustic Waves from a Moving Layer written by George G. Steinmetz and published by . This book was released on 1972 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The refraction of acoustic waves by a moving medium layer is theoretically treated and the expressions for reflection and transmission coefficients are determined. The moving medium layer velocity is assumed to have a space dependence in one direction. A partitioning of the moving medium layer into constant-velocity sublayers is introduced and the number of sublayers is allowed to increase until the reflection and transmission coefficients converage to their respective values. Numerical results for several sublayer approximations of Poiseuille's flow are presented as functions of the moving layer velocity for several angles of incidence of the acoustic wave. The degenerate case of single constant-velocity layer is also treated, both theoretically and by a numerical analysis.
Download or read book Understanding Acoustics written by Steven L. Garrett and published by Springer. This book was released on 2017-02-24 with total page 913 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook provides a unified approach to acoustics and vibration suitable for use in advanced undergraduate and first-year graduate courses on vibration and fluids. The book includes thorough treatment of vibration of harmonic oscillators, coupled oscillators, isotropic elasticity, and waves in solids including the use of resonance techniques for determination of elastic moduli. Drawing on 35 years of experience teaching introductory graduate acoustics at the Naval Postgraduate School and Penn State, the author presents a hydrodynamic approach to the acoustics of sound in fluids that provides a uniform methodology for analysis of lumped-element systems and wave propagation that can incorporate attenuation mechanisms and complex media. This view provides a consistent and reliable approach that can be extended with confidence to more complex fluids and future applications. Understanding Acoustics opens with a mathematical introduction that includes graphing and statistical uncertainty, followed by five chapters on vibration and elastic waves that provide important results and highlight modern applications while introducing analytical techniques that are revisited in the study of waves in fluids covered in Part II. A unified approach to waves in fluids (i.e., liquids and gases) is based on a mastery of the hydrodynamic equations. Part III demonstrates extensions of this view to nonlinear acoustics. Engaging and practical, this book is a must-read for graduate students in acoustics and vibration as well as active researchers interested in a novel approach to the material.
