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arXiv · 2505.14373

Time domain analysis of microstructured materials through the reduced relaxed micromorphic model

Abstract

Microstructured materials, such as architected metamaterials and phononic crystals, exhibit complex wave propagation phenomena due to their internal structure. While full-scale numerical simulations can capture these effects, they are computationally demanding, especially in time-domain analyses. To overcome this limitation, effective continuum models have been developed to approximate the macroscopic behavior of these materials while retaining key microscale effects. In this work we investigate the time-domain dynamic response of microstructured materials and focus on their effective micromorphic counterparts. We compare direct numerical simulations of discrete microstructures with predictions from micromorphic models to assess their accuracy in capturing transient wave phenomena. Our findings provide new insights into the applicability and limitations of micromorphic models in time-dependent analyses, contributing to the development of improved predictive tools for metamaterial design and engineering applications.

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Gianluca Rizzi, Angela Madeo. 2025-05-20. Time domain analysis of microstructured materials through the reduced relaxed micromorphic model. https://arxiv.org/abs/2505.14373

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