Comte-Bellot / Fowcs-Williams Aero- and Hydro-Acoustics

IUTAM Symposium, Ecole Centrale de Lyon, 3–6 July, 1985
1986
ISBN: 978-3-642-82758-7
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 550 Seiten, eBook

Reihe: IUTAM Symposien

Zielgruppe

Research

Autoren/Hrsg.

Comte-Bellot, Genevieve

Fowcs-Williams, John E.

Inhaltsverzeichnis

Session I — “Diffraction.- Diffraction and radiation.- Influence of airfoil mean loading on convected gust interaction noise.- Acoustic waves emitted by vortex-body interaction.- Non-steady flow over a trailing edge — An experimental study.- An experimental study of the influence of mean flow on acoustic dissipation by vorticity production at edges.- Session II — “Active Control”.- Active noise control.- The constraint of causality on an active control system.- Acoustic pressure and intensity distributions in finite length active noise control systems.- The active minimisation of harmonic enclosed sound fields.- Session III — “Source Mechanisms”.- Source identification techniques — A critical evaluation.- Sound generation in the ocean under a turbulent airflow.- Acoustic radiation fron vortex solitons.- Session IV — “Rotor Noise”.- Noise of high speed surfaces.- Comparison of two propeller source models for aircraft interior noise studies.- Modelling of trailing edge flow tones in elastic structures.- The Ffowcs Williams-Hawkings equation-fifteen years of research.- Session V — “Thermo Acoustics”.- Thermoacoustic sources.- Active control of the noise from a Rijke tube.- Coherence aspects of acoustic wave transmission through a medium with temperature fluctuations.- Session VI — “Computational Acoustics”.- Numerical methods in acoustics.- Computational aeroacoustics — Present status and future promise.- The wavenumber-frequency spectrum of the wall pressure field computed from a numerical solution of the Navier Stockes equation.- A mixed functional for the numerical resolution of fluid-structure interaction problems.- Rayonnement d’une plaque mince, homogène ou raidie, encastrée dans un plan parfaitement rigide.- Session VII— “Hydroacoustics”.- Topics in hydroacoustics.- Interaction hydroélastique entre une plaque et un écoulement.- The acoustics of disturbed steady motions.- Temporal variability in shallow water acoustic transmission and its correlation with the environment.- Underwater sound generation by waterhammer.- Session VIII — “Hydroacoustics (C’ nd)”:.- Finite amplitude sound beams resulting from nonlinear vibration of a circular membrane undergoing axisymmetric resonant excitation.- Theoretical prediction for the reduction of flow-induced noise on a plane surface.- The vibration of a periodically ring-stiffened, fluid-loaded cylinder.- Surface inpedance loading of panels.- Session IX — “Flow Noise”.- Excitation of instability waves.- On noise generated by turbulence in a pipe downstream of a discontinuous area enlargement.- Acoustoelasticity of a panel backed by a rectangular cavity.- Near field pressure fluctuations of a circular jet.- Experimental investigation of near and far acoustic field of a small turbojet.- Session X — “Aeroacoustics”.- Wind tunnel investigation of aeolian tones from rough surface cylinders.- Characterising pressure fluctuations on the wall of a circular cylinder perpendicular to a flow.- Flow effects on measurement of the modal decomposition of acoustic field in a hard wall cylindrical duct.- The effects of density on subsonic jet noise.- Session XI — “Acoustics Of Unstable Flows”.- Acoustics of unstable flows.- Hydrodynamic instabilities and surface waves in a flow over an impedance wall.- Wake-induced shear layer excitation in a basic annular jet.- Transient vortex modelling of flow induced acoustic resonances near cavities or obstructions in ducts.- Etude du couplage acoustique-instabilités aérodynamiques sur unemaquette de statoréacteur.- Session XII — “Flow-Acoustic Interaction”.- On the influence of opening geometry on noise from air jets.- Response of a flat plate turbulent boundary layer to intense sound waves moving in the upstream direction.- An experiment on sound turbulence interaction by impulsive sound tube.- Disturbance induced by a boundary layer on sound sources location — Application to the case of a vehicle.