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arXiv · 0705.2754

Acoustic response of a rigid frame porous medium slab with a periodic set of inclusions

Jean-Philippe Groby·Armand Wirgin·Laurent De Ryck·Walter Lauriks
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Abstract

The acoustic response of a rigid frame porous slab with a periodic set of inclusions is calculated by use of a multipole method. The acoustic properties, in particular the absorption, of such a structure are then derived and studied. Numerical results together with a modal analysis show that the addition of a periodic set of high-contrast inclusions leads to quasi-modes excitation of both the slab and the gratings, and to a large increase of the acoustic absorption of the initial slab, this being partly due to the quasi-modes excitation.

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Jean-Philippe Groby, Armand Wirgin, Laurent De Ryck, Walter Lauriks. 2007-05-18. Acoustic response of a rigid frame porous medium slab with a periodic set of inclusions. https://arxiv.org/abs/0705.2754

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