Low-frequency metamaterial absorbers for mitigating sound and vibration

Abstract

Low-frequency wave absorption in domains of acoustics and mechanics is an old yet not fully closed topic in terms of both theoretical research and practical applications. This thesis intends to present a comprehensive study on this subject by reviewing recent breakthroughs and proposing new metamaterial-based designs aiming for simpler construction, better compactness, and higher flexibility. I start with revisiting the development of metamaterial research, elucidating its fundamental physical pictures and highlighting new wave control possibilities offered by it, followed by a detailed review of sound absorption structures, for both conventional types and metamaterial-based types, with an emphasis on the recent breakthrough of causality-law-aspired optimal absorber design. Finally, to...[ Read more ]