Sound absorption by perforated walls along boundaries

Patrizia Donato; Agnes Lamacz; Ben Schweizer

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arXiv · 2006.02701

Sound absorption by perforated walls along boundaries

Patrizia Donato·Agnes Lamacz·Ben Schweizer

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Abstract

We analyze the Helmholtz equation in a complex domain. A sound absorbing structure at a part of the boundary is modelled by a periodic geometry with periodicity $\varepsilon>0$. A resonator volume of thickness $\varepsilon$ is connected with thin channels (opening $\varepsilon^3$) with the main part of the macroscopic domain. For this problem with three different scales we analyze solutions in the limit $\varepsilon\to 0$ and find that the effective system can describe sound absorption.

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Patrizia Donato, Agnes Lamacz, Ben Schweizer. 2020-06-04. Sound absorption by perforated walls along boundaries. https://arxiv.org/abs/2006.02701

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