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Institute Jean le Rond d’AlembertMechanics, Acoustics, Energetics

Univ. Paris 6 - UPMC and CNRS, Paris and Saint-Cyr l’École http://www.dalembert.upmc.fr

A hundred staff members in five teams :Complex Fluids and Hydrodynamic Instabilities FCIH

Reacting Fluids and Turbulence FRTLutheries, Acoustics, Music LAM

Modelling, Propagation and Acoustic Imaging MPIAMechanics and Engineering of Solids and Structures MISES

Director: Stéphane Zaleski

UMR 7190

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Droplet impact on a liquid layerHelical vortices (occurs in helicopter-blade wakes, windmills)

Fluid biomechanics: Modeling sleep apnea

FCIH: Complex Fluids and Hydrodynamic Instabilities Head: Maurice RossiFluid mechanics in complex configurations, instabilities, two-phase flow, granular media.

Granular flow

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Vorticity field arising from radiated acoustic pressurenumerical simulation

Variability of the spatial distribution of the vorticity field in a 2D forced mixing layer.Numerical simulation. The effect of the forcing amplitude is shown.

FRT : Reacting Fluids and Turbulence Head: Pierre SagautLarge eddy simulation, internal combustion engines, uncertainty propagation.

Rapid Compression DeviceThe inset shows chemoluminescence data that track the emission of free radicals in the reacting zone.

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Use of a time reversal mirror to focus on the harmony tableThe identification of relevant parameters for the quality of musical instruments (violins, flutes, harpsichords) relies on

specific techniques.

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Nozzle loudspeaker enclosureThese shapes are motivated by the need

to minimize the sound distortion by jets and vortices.

Sound recording in urban environment

Correlating sound and measurement is of particular interest here.

LAM : Lutheries, Acoustics, Music Head: Hugues GenevoisAcoustical, mechanical, and social science studies of music and sound.

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Reconstructing the vorticity field in the wake of a delta wing by acoustic

tomographyAcoustic rays contain information about the media

they travel in, here vorticity is reconstructed.

Plate with piezolelectric transducersThe goal is to limit acoustic radiation using active

devices.

Wave fronts on the surface of a copper cristal. Comparison of Theory and Experiment.

Wavespeeds and wavefronts on the surface of a cristal are predicted and measured.

MPIA : Modelling, Propagation and Acoustic Imaging Head: Bernard Collet wave propagation in radom media, nonlinear waves, vibration, underwater imaging, time reversal.

Numerical simulation of an acoustic shock wave near a fold caustic.

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Localisation of micro-stresses in concrete or injected sand.

MISES : Mechanics and Engineering of Solids and Structures Head: Sébastien Neukirch damage, rupture, slender elastic bodies, structural optimization.

Spontaneous spiraling of slender elastic bodies

Ductilefracture

Optimisation of composite materials