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DOE OSTI · 1569621

Acoustic cloaking: Geometric transform, homogenization and a genetic algorithm

Pomot, Lucas·Payan, Cédric·Remillieux, Marcel·Guenneau, Sébastien
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Abstract

A general process is proposed to experimentally design anisotropic inhomogeneous metamaterials obtained through a change of coordinates in the Helmholtz equation. The method is applied to the case of a cylindrical transformation that allows cloaking to be performed. To approximate such complex metamaterials we apply results of the theory of homogenization and combine them with a genetic algorithm. To illustrate the power of our approach, we design three types of cloaks composed of isotropic concentric layers structured with three types of perforations: curved rectangles, split rings and crosses. These cloaks have parameters compatible with existing technology and they mimic the behavior of the transformed material. Numerical simulations have been performed to qualitatively and quantitatively study the cloaking efficiency of these metamaterials.

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36 MATERIALS SCIENCECloakingElastic WavesGenetic AlgorithmGeometric TransformationHelmholtz EquationHomogenizationMachine learningMetamaterials

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Pomot, Lucas, Payan, Cédric, Remillieux, Marcel, Guenneau, Sébastien. 2019-09-17. Acoustic cloaking: Geometric transform, homogenization and a genetic algorithm. https://doi.org/10.1016/j.wavemoti.2019.102413

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