Computational material design for acoustic cloaking

A topology optimization technique based on the topological derivative and the level set function is utilized to design/synthesize the microstructure of a pentamode material for an acoustic cloaking device. The technique provides a microstructure consisting of a honeycomb lattice composed of needle-l...

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Detalles Bibliográficos
Autores: Gustavo Méndez, Carlos, Podestá, Juan Manuel, Lloberas Valls, Oriol, Toro, Sebastian, Huespe, Alfredo Edmundo, Oliver, Javier
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/38237
Acceso en línea:http://hdl.handle.net/11336/38237
Access Level:acceso abierto
Palabra clave:transformation acoustic applications
topological derivative
extremal material
topology optimization
Descripción
Sumario:A topology optimization technique based on the topological derivative and the level set function is utilized to design/synthesize the microstructure of a pentamode material for an acoustic cloaking device. The technique provides a microstructure consisting of a honeycomb lattice composed of needle-like and joint members. The resulting metamaterial shows a highly anisotropic elastic response with effective properties displaying a ratio between bulk and shear moduli of almost three orders of magnitude. Furthermore, in accordance with previous works in the literature, it can be asserted that this kind of microstructure can be realistically fabricated. The adoption of a topology optimization technique as a tool for the inverse design of metamaterials with applications to acoustic cloaking problems is one contribution of this paper. However, the most important achievement refers to the analysis and discussion revealing the key role of the external shape of the prescribed domain where the optimization problem is posed. The efficiency of the designed microstructure is measured by comparing the scattering wave fields generated by acoustic plane waves impinging on bare and cloaked bodies. Copyright © 2017 The Authors. International Journal for Numerical Methods in Engineering Published by John Wiley & Sons Ltd.