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arXiv · 2109.14658

Cloaking strategy for Love waves

Abstract

Love waves are antiplane elastic waves which propagate along the surface of a heterogeneous medium. Under time-harmonic regime, they are governed by a scalar equation of the Helmholtz type. We exploit the invariance of this governing equation under an in-plane arbitrary coordinate transformation to design broadband cloaks for surface defects. In particular, we apply transformation elastodynamics to determine the anisotropic, position dependent, mechanical properties of ideal cloaks able to hide triangular and parabolic-shaped defects. Dispersion analysis and time-harmonic numerical simulations are employed to validate the proposed strategy. Next, we utilize layered monoclinic materials, with homogenized properties matching those of ideal cloaks, to design feasible cloaks. The performance of the layered cloaks is validated via time-harmonic numerical simulations which show a significant reduction of the defect-generated scattered fields.

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Z. Chatzopoulos, A. Palermo, S. Guenneau, A. Marzani. 2021-09-29. Cloaking strategy for Love waves. https://doi.org/10.1016/j.eml.2021.101564

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