Relaxed micromorphic model of transient wave propagation in anisotropic band-gap metastructures

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:162

Article

Barbagallo, Gabriele¹  Tallarico, Domenico¹  D'Agostino, Marco Valerio¹  Aivaliotis, Alexios¹  Neff, Patrizio²  Madeo, Angela¹ 

[1] Univ Lyon, INSA Lyon, GEOMAS, 20 Ave Albert Einstein, F-69621 Villeurbanne, France

[2] Univ Duisburg Essen, Chair Nonlinear Anal & Modelling, Fak Math, Math Carree, Thea Leymann Str 9, D-45127 Essen, Germany

关键词: Elastic metamaterials;    Transient dynamic response;    Anisotropy;    Relaxed micromorphic model;   

DOI  :  10.1016/j.ijsolstr.2018.11.033

来源: Elsevier

【 摘 要 】

In this paper, we show that the transient waveforms arising from several localised pulses in a microstructured material can be reproduced by a corresponding generalised continuum of the relaxed micromorphic type. Specifically, we compare the dynamic response of a bounded micro-structured material to that of bounded continua with special kinematic properties: (i) the relaxed micromorphic continuum and (ii) an equivalent Cauchy linear elastic continuum. We show that, while the Cauchy theory is able to describe the overall behaviour of the metastructure only at low frequencies, the relaxed micromorphic model goes far beyond by giving a correct description of the pulse propagation in the frequency band-gap and at frequencies intersecting the optical branches. In addition, we observe a computational time reduction associated with the use of the relaxed micromorphic continuum, compared to the sensible computational time needed to perform a transient computation in a micro-structured domain. (C) 2018 Elsevier Ltd. All rights reserved.

【 授权许可】

Free