Download or read book Modeling of Turbulence Generated Noise in Jets written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-21 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: A numerically calculated Green's function is used to predict jet noise spectrum and its far-field directivity. A linearized form of Lilley's equation governs the non-causal Green s function of interest, with the non-linear terms on the right hand side identified as the source. In this paper, contributions from the so-called self- and shear-noise source terms will be discussed. A Reynolds-averaged Navier-Stokes solution yields the required mean flow as well as time- and length scales of a noise-generating turbulent eddy. A non-compact source, with exponential temporal and spatial functions, is used to describe the turbulence velocity correlation tensors. It is shown that while an exact non-causal Green's function accurately predicts the observed shift in the location of the spectrum peak with angle as well as the angularity of sound at moderate Mach numbers, at high subsonic and supersonic acoustic Mach numbers the polar directivity of radiated sound is not entirely captured by this Green's function. Results presented for Mach 0.5 and 0.9 isothermal jets, as well as a Mach 0.8 hot jet conclude that near the peak radiation angle a different source/Green's function convolution integral may be required in order to capture the peak observed directivity of jet noise. Khavaran, Abbas and Bridges, James Glenn Research Center NASA/TM-2004-213105, AIAA Paper 2004-2983, E-14580
Download or read book The Generation and Radiation of Supersonic Jet Noise Theory of turbulence generated jet noise noise radiation from upstream sources and combustion noise written by and published by . This book was released on 1972 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Jet noise physics and modeling using firstprinciples simulations written by and published by DIANE Publishing. This book was released on with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeroacoustics of Flight Vehicles written by Harvey H. Hubbard and published by . This book was released on 1991 with total page 620 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Theory of Turbulent Jets written by Genrikh Naumovich Abramovich and published by Mit Press. This book was released on 1963 with total page 671 pages. Available in PDF, EPUB and Kindle. Book excerpt: The author's first monograph on turbulent jets, in 1936, dealt solely with a free submerged jet. Since that time, the theory of the turbulent jet has been developed in many published works both in the USSR and abroad: it has been enriched with a large amount of experimental material and has been applied in many new fields of engineering. In the last 10 years very substantial progress has been made, and it has now become possible to go beyond the free submerged jet and to solve the problem of a jet in a stream of fluid, to take into account the interaction between the jet and solid walls, to ascertain the relationship between the contour of the jet and the ratio of its density to the density of the surrounding medium, and to establish the characteristic features of a supersonic jet. This monograph contains the results of further research by the author and his colleagues, as well as a critical reappraisal of the more important theoretical and experimental data published by other investigators. The first section deals with the theory of a turbulent jet of incompressible fluid. It gives a systematic analysis of numerous experimental data on velocity profiles, temperature, and the impurity concentration, as well as the outlines of the turbulent mixing lone. The second section sets forth the theory of turbulent gas jets, including strongly preheated and supersonic jets. The theory of free turbulence in a gas, suitable in principle for any degree of compressibility, is revised, and the equations are derived for motion and heat exchange in the boundary layer of a jet at very high temperature. The third section solves several problems of the spreading of jets in finite and semifinite space, and the fourth section describes various applications of the theory of jets, many of which are reported for the first time or have been significantly revised.
Download or read book NASA Reference Publication written by and published by . This book was released on 1977 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aeroacoustics of Flight Vehicles written by Harvey H. Hubbard and published by . This book was released on 1991 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1992 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Advances in Computational and Experimental Mechanics Vol I written by D. Maity and published by Springer Nature. This book was released on 2022-01-01 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book (Vol. - I) presents select proceedings of the first Online International Conference on Recent Advances in Computational and Experimental Mechanics (ICRACEM 2020) and focuses on theoretical, computational and experimental aspects of solid and fluid mechanics. Various topics covered are computational modelling of extreme events; mechanical modelling of robots; mechanics and design of cellular materials; mechanics of soft materials; mechanics of thin-film and multi-layer structures; meshfree and particle based formulations in continuum mechanics; multi-scale computations in solid mechanics, and materials; multiscale mechanics of brittle and ductile materials; topology and shape optimization techniques; acoustics including aero-acoustics and wave propagation; aerodynamics; dynamics and control in micro/nano engineering; dynamic instability and buckling; flow-induced noise and vibration; inverse problems in mechanics and system identification; measurement and analysis techniques in nonlinear dynamic systems; multibody dynamical systems and applications; nonlinear dynamics and control; stochastic mechanics; structural dynamics and earthquake engineering; structural health monitoring and damage assessment; turbomachinery noise; vibrations of continuous systems, characterization of advanced materials; damage identification and non-destructive evaluation; experimental fire mechanics and damage; experimental fluid mechanics; experimental solid mechanics; measurement in extreme environments; modal testing and dynamics; experimental hydraulics; mechanism of scour under steady and unsteady flows; vibration measurement and control; bio-inspired materials; constitutive modelling of materials; fracture mechanics; mechanics of adhesion, tribology and wear; mechanics of composite materials; mechanics of multifunctional materials; multiscale modelling of materials; phase transformations in materials; plasticity and creep in materials; fluid mechanics, computational fluid dynamics; fluid-structure interaction; free surface, moving boundary and pipe flow; hydrodynamics; multiphase flows; propulsion; internal flow physics; turbulence modelling; wave mechanics; flow through porous media; shock-boundary layer interactions; sediment transport; wave-structure interaction; reduced-order models; turbo-machinery; experimental hydraulics; mechanism of scour under steady and unsteady flows; applications of machine learning and artificial intelligence in mechanics; transport phenomena and soft computing tools in fluid mechanics. The contents of these two volumes (Volumes I and II) discusses various attributes of modern-age mechanics in various disciplines, such as aerospace, civil, mechanical, ocean engineering and naval architecture. The book will be a valuable reference for beginners, researchers, and professionals interested in solid and fluid mechanics and allied fields.
Download or read book The Handbook of Phonetic Sciences written by William J. Hardcastle and published by John Wiley & Sons. This book was released on 2012-09-17 with total page 899 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thoroughly revised and updated, the second edition of The Handbook of Phonetic Sciences provides an authoritative account of the key topics in both theoretical and applied areas of speech communication, written by an international team of leading scholars and practitioners. Combines new and influential research, along with articulate overviews of the key topics in theoretical and applied areas of speech communication Accessibly structured into five major sections covering: experimental phonetics; biological perspectives; modelling speech production and perception; linguistic phonetics; and speech technology Includes nine entirely new chapters on topics such as phonetic notation and sociophonetics, speech technology, biological perspectives, and prosody A streamlined and re-oriented structure brings all contributions up-to-date with the latest research, whilst maintaining the features that made the first edition so useful
Download or read book Report Naval Ship Research and Development Center written by David W. Taylor Naval Ship Research and Development Center and published by . This book was released on 1958 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Video Speech and Audio Signal Processing and Associated Standards written by Vijay Madisetti and published by CRC Press. This book was released on 2018-09-03 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: Now available in a three-volume set, this updated and expanded edition of the bestselling The Digital Signal Processing Handbook continues to provide the engineering community with authoritative coverage of the fundamental and specialized aspects of information-bearing signals in digital form. Encompassing essential background material, technical details, standards, and software, the second edition reflects cutting-edge information on signal processing algorithms and protocols related to speech, audio, multimedia, and video processing technology associated with standards ranging from WiMax to MP3 audio, low-power/high-performance DSPs, color image processing, and chips on video. Drawing on the experience of leading engineers, researchers, and scholars, the three-volume set contains 29 new chapters that address multimedia and Internet technologies, tomography, radar systems, architecture, standards, and future applications in speech, acoustics, video, radar, and telecommunications. This volume, Video, Speech, and Audio Signal Processing and Associated Standards, provides thorough coverage of the basic foundations of speech, audio, image, and video processing and associated applications to broadcast, storage, search and retrieval, and communications.
Download or read book Numerical Simulation of Turbulent Flows and Noise Generation written by Christophe Brun and published by Springer Science & Business Media. This book was released on 2009-03-07 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: Large Eddy Simulation (LES) is a high-fidelity approach to the numerical simulation of turbulent flows. Recent developments have shown LES to be able to predict aerodynamic noise generation and propagation as well as the turbulent flow, by means of either a hybrid or a direct approach. This book is based on the results of two French/German research groups working on LES simulations in complex geometries and noise generation in turbulent flows. The results provide insights into modern prediction approaches for turbulent flows and noise generation mechanisms as well as their use for novel noise reduction concepts.
Download or read book Theoretical and Experimental Aerodynamics written by Mrinal Kaushik and published by Springer. This book was released on 2018-12-15 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended as a text for undergraduate and graduate courses in aerodynamics, typically offered to students of aerospace and mechanical engineering programs. It covers all aspects of aerodynamics. The book begins with a description of the standard atmosphere and basic concepts, then moves on to cover the equations and mathematical models used to describe and characterize flow fields, as well as their thermodynamic aspects and applications. Specific emphasis is placed on the relation between concepts and their use in aircraft design. Additional topics of interest to the reader are presented in the Appendix, which draws on the teachings provided in the text. The book is written in an easy to understand manner, with pedagogical aids such as chapter overviews, summaries, and descriptive and objective questions to help students evaluate their progress. Atmospheric and gas tables are provided to facilitate problem solving. Lastly, a detailed bibliography is included at the end of each chapter to provide students with further resources. The book can also be used as a text for professional development courses in aerodynamics.
Download or read book Noise Sources in Turbulent Shear Flows Fundamentals and Applications written by Roberto Camussi and published by Springer Science & Business Media. This book was released on 2013-02-11 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt: The articles in this volume present the state-of-the-art in noise prediction, modeling and measurement. The articles are partially based on class notes provided during the course `Noise sources in turbulent shear flows', given at CISM on April 2011. The first part contains general concepts of aero acoustics, including vortex sound theory and acoustic analogies, in the second part particular emphasis is put into arguments of interest for engineers and relevant for aircraft design: jet noise, airfoil broadband noise, boundary layer noise (including interior noise and its control) and the concept of noise sources, their theoretical modeling and identification in turbulent lows. All these arguments are treated extensively with the inclusion of many practical examples and references to engineering applications.
Download or read book Computational Acoustics of Noise Propagation in Fluids Finite and Boundary Element Methods written by Steffen Marburg and published by Springer Science & Business Media. This book was released on 2008-02-27 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book provides a survey of numerical methods for acoustics, namely the finite element method (FEM) and the boundary element method (BEM). It is the first book summarizing FEM and BEM (and optimization) for acoustics. The book shows that both methods can be effectively used for many other cases, FEM even for open domains and BEM for closed ones. Emphasis of the book is put on numerical aspects and on treatment of the exterior problem in acoustics, i.e. noise radiation.
Download or read book Analysis of Noise Produced by an Orderly Structure of Turbulent Jets written by Jay C. Hardin and published by . This book was released on 1973 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The orderly structure which has been observed recently by numerous researchers within the transition region of subsonic turbulent jets is analyzed to reveal its noise-producing potential. For a circular jet, this structure is molded as a train of toroidal vortex rings which are formed near the jet exit and propagate downstream. The noise produced by the model is evaluated from a reformulation of Lighthill's expression for the far-field acoustic density, which emphasizes the importance of the vorticity within the turbulent flow field. It is shown that the noise production occurs mainly close to the jet exit and depends primarily upon temporal changes in the toroidal radii. The analysis suggests that the process of formation of this regular structure may also be an important contribution of the high-frequency jet noise. These results may be helpful in the understanding of jet-noise generation and in new approaches to jet-noise suppression.
