Author : Sundaram C. Venkitarama
Publisher :
Page : 226 pages
File Size : 35,11 MB
Release : 1981
Category : Jet planes
ISBN :
Author :
Publisher :
Page : 702 pages
File Size : 26,31 MB
Release : 1994
Category : Aeronautics
ISBN :
Author :
Publisher :
Page : 1048 pages
File Size : 31,57 MB
Release :
Category : Science
ISBN :
Author : National Aeronautics and Space Administration (NASA)
Publisher : Createspace Independent Publishing Platform
Page : 26 pages
File Size : 28,7 MB
Release : 2018-06-19
Category :
ISBN : 9781721276707
An acoustic prediction capability for supersonic axisymmetric jets was developed on the basis of OVERFLOW Navier-Stokes CFD (Computational Fluid Dynamics) code of NASA Langley Research Center. Reynolds-averaged turbulent stresses in the flow field are modeled with the aid of Spalart-Allmaras one-equation turbulence model. Appropriate acoustic and outflow boundary conditions were implemented to compute time-dependent acoustic pressure in the nonlinear source-field. Based on the specification of acoustic pressure, its temporal and normal derivatives on the Kirchhoff surface, the near-field and the far-field sound pressure levels are computed via Kirchhoff surface integral, with the Kirchhoff surface chosen to enclose the nonlinear sound source region described by the CFD code. The methods are validated by a comparison of the predictions of sound pressure levels with the available data for an axisymmetric turbulent supersonic (Mach 2) perfectly expanded jet. Kandula, Max and Caimi, Raoul and Steinrock, T. (Technical Monitor) Kennedy Space Center NASA/TM-2001-210263, NAS 1.15:210263
Author :
Publisher :
Page : 974 pages
File Size : 11,47 MB
Release : 1999
Category : Aeronautics
ISBN :
Author : Roberto Camussi
Publisher : Springer Science & Business Media
Page : 453 pages
File Size : 12,55 MB
Release : 2013-02-11
Category : Technology & Engineering
ISBN : 3709114586
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.
Author : Claus Wagner
Publisher : Cambridge University Press
Page : 389 pages
File Size : 48,71 MB
Release : 2007-01-15
Category : Technology & Engineering
ISBN : 1139463160
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.
Author : Max Kandula
Publisher : BiblioGov
Page : 28 pages
File Size : 18,79 MB
Release : 2013-08
Category :
ISBN : 9781289269005
An acoustic prediction capability for supersonic axisymmetric jets was developed on the basis of OVERFLOW Navier-Stokes CFD (Computational Fluid Dynamics) code of NASA Langley Research Center. Reynolds-averaged turbulent stresses in the flow field are modeled with the aid of Spalart-Allmaras one-equation turbulence model. Appropriate acoustic and outflow boundary conditions were implemented to compute time-dependent acoustic pressure in the nonlinear source-field. Based on the specification of acoustic pressure, its temporal and normal derivatives on the Kirchhoff surface, the near-field and the far-field sound pressure levels are computed via Kirchhoff surface integral, with the Kirchhoff surface chosen to enclose the nonlinear sound source region described by the CFD code. The methods are validated by a comparison of the predictions of sound pressure levels with the available data for an axisymmetric turbulent supersonic (Mach 2) perfectly expanded jet.
Author : American Institute of Aeronautics and Astronautics. Technical Information Service
Publisher :
Page : 196 pages
File Size : 16,37 MB
Release : 1993
Category : AIAA paper
ISBN :
Author :
Publisher :
Page : 568 pages
File Size : 10,35 MB
Release : 1972
Category : Mechanics, Applied
ISBN :
