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arXiv · 1206.4577

Metadamping: An emergent phenomenon in dissipative metamaterials

Mahmoud I. Hussein·Michael J. Frazier
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Abstract

We theoretically demonstrate the concept of metadamping in dissipative metamaterials. We consider an infinite mass-spring chain with repeated local resonators and a statically equivalent periodic chain whose wave propagation characteristics are based on Bragg scattering. For each system we introduce identical viscous damping (dashpot) elements and compare the damping ratio associated with all Bloch modes. We find that the locally resonant metamaterial exhibits higher dissipation overall which indicates a damping emergence phenomena due to the presence of local resonance. We conclude our investigation by quantifying the degree of emergent damping as a function of the long-wave speed of sound in the medium or the static stiffness.

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Mahmoud I. Hussein, Michael J. Frazier. 2012-06-21. Metadamping: An emergent phenomenon in dissipative metamaterials. https://doi.org/10.1016/j.jsv.2013.04.041

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