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dc.contributor.advisorPanneton, Raymondfr
dc.contributor.authorPerrot, Camillefr
dc.date.accessioned2014-05-15T12:32:32Z
dc.date.available2014-05-15T12:32:32Z
dc.date.created2006fr
dc.date.issued2006fr
dc.identifier.urihttp://savoirs.usherbrooke.ca/handle/11143/1799
dc.description.abstractThe fundamental issue of determining acoustic properties of porous media from their local geometry is examined in this PhD dissertation thesis, thanks to a sample of open-cell aluminum foam analyzed by axial computed microtomography. Various geometric properties are measured to characterize the experimental sample at the cell size level. This is done in order to reconstruct a porous medium by means of idealized three- and two- dimensional unit-cells.The frequency dependant thermal and velocity fields governing the propagation and dissipation of acoustic waves through rigid porous media are computed by Brownian motion simulation and the finite element method, respectively. Macroscopic behavior is derived by spatial averaging of the local fields. Our results are compared to experimental data obtained from impedance tube measurements. Firstly, this approach leads to the identification of the macroscopic parameters involved in Pride and Lafarge semiphenomenological models. Secondly, it yields a direct access to thermal and viscous dynamic permeabilities. However, the bi-dimensional model underestimates the static viscous permeability as well as the viscous characteristic length; what thus require a three-dimensional implementation.fr
dc.language.isofrefr
dc.publisherUniversité de Sherbrookefr
dc.rights© Camille Perrotfr
dc.subjectDynamic thermal and viscous permeabilitiesfr
dc.subjectBrownian motionfr
dc.subjectMicrotomographyfr
dc.subjectReconstruction methodfr
dc.subjectOpen-cell foamsfr
dc.subjectPorous mediafr
dc.subjectAcousticsfr
dc.subjectMicrostructurefr
dc.titleMicrostructure et macro-comportement acoustique : approche par reconstruction d'une cellule élémentaire représentativefr
dc.typeThèsefr
tme.degree.disciplineGénie mécaniquefr
tme.degree.grantorFaculté de géniefr
tme.degree.grantotherInstitut National des Faculté des sciences Appliquées de Lyonfr
tme.degree.levelDoctoratfr
tme.degree.namePh.D.fr


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