论文期刊

A thin low-frequency broadband metasurface with multi-order sound absorption




作者: Chong Rui Liu, Jiu Hui Wu, Xu Chen, and Fuyin Ma
发表/完成日期: 2018-12-12
期刊名称: J. Phys. D: Appl. Phys.
期卷: Vol.52, No.10, 2019
相关文章: LiuChongrui_2019_J._Phys._D__Appl._Phys._52_105302.pdf   
论文简介
We present a theoretical and experimental realization of a thin multi-unit metasurface with
multi-order sound absorption that exhibits a continuous near-perfect absorption spectrum
in the broadband range of 450 Hz–1360 Hz. The metasurface unit is a perforated composite
Helmholtz-resonator (PCHR) that is constructed by inserting one or more separating plates
with a small hole into the interior of a Helmholtz resonator (HR). The multi-order sound
absorption mechanism can be achieved so that with the original absorption peak and the
structural size unchanged, multiple near-perfect peaks are obtained in higher frequencies
by a PCHR unit. This extraordinary multi-peak performance is the result of the upgraded
multi-degree-of-freedom system with the separating plates, which is explained well by
the equivalent acoustic circuit. The specifc absorption properties of the PCHR unit are
investigated thoroughly with a theoretical approach similar to the plane wave expansion
method, and verifed via the fnite element simulations. On this basis, by precisely balancing
the parameters of each unit, the absorption bandwidth of the subwavelength 8-unit metasurface
is dramatically broadened about 65% by the proposed mechanism. This work would offer
a new guidance for the achievement of the wider absorption band and has great potential in
engineering applications.