Experimental Observation of Reversed Doppler Effects in Acoustic Metamaterials

Shilong Zhai; Xiaopeng Zhao; Song Liu; Chunrong Luo

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arXiv · 1505.05871

Experimental Observation of Reversed Doppler Effects in Acoustic Metamaterials

Shilong Zhai·Xiaopeng Zhao·Song Liu·Chunrong Luo

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Abstract

This paper reports an experimental observation of broadband reversed Doppler effects using an acoustic metamaterial with seven flute-like double-meta-molecule clusters. Simulations and experiments verify that this locally resonant acoustic metamaterial with simultaneous negative elastic modulus and mass density can realize negative refraction in a broad frequency range. The constructed metamaterial exhibits broadband reversed Doppler effects. The frequency shift increases continuously as the frequency increases. The assembling of double-meta-molecule clusters introduces a new direction in designing double-negative acoustic metamaterials in an arbitrarily broad frequency range and other various applications.

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Shilong Zhai, Xiaopeng Zhao, Song Liu, Chunrong Luo. 2015-05-21. Experimental Observation of Reversed Doppler Effects in Acoustic Metamaterials. https://arxiv.org/abs/1505.05871

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