Aero- and Hydro-Acoustics -

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Résumé :
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, homog?ne ou raidie, encastr?e dans un plan parfaitement rigide.- Session VII- Hydroacoustics.- Topics in hydroacoustics.- Interaction hydro?lastique entre une plaque et un ?coulement.- 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-instabilit?s a?rodynamiques sur unemaquette de stator?acteur.- 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 t...