Transmission Loss and Dynamic Response of Hierarchical Membrane-Type Acoustic Metamaterials

2020 ◽  
Vol 142 (2) ◽  
Author(s):  
William T. Edwards ◽  
Chia-Ming Chang ◽  
Geoffrey McKnight ◽  
Adam Sorensen ◽  
Steven R. Nutt
Keyword(s):  
Transmission Loss ◽  
Analytical Data ◽  
Analytical Models ◽  
Acoustic Metamaterials ◽  
Length Scales ◽  
Acoustic Performance ◽  
Membrane Type ◽  
The Individual ◽  
Analytical Tools ◽  
Novel Design

Abstract A deployment-scale array of locally resonant membrane-type acoustic metamaterials (MAMs) is fabricated. The acoustic performance of the array is measured in a transmission loss chamber, and a complex interaction between the individual cell and the array length scales is shown to exist. Transmission behavior of both the membrane and the array are independently studied using analytical models, and a method for estimating transmission loss through the structure that combines vibroacoustic predictions from both length scales is presented and shown to agree with measurements. Degradation of transmission loss performance often associated with scaling individual MAM cells into arrays is explained using analytical tools and verified using laser vibrometry. A novel design for hierarchical locally resonant acoustic metamaterials is introduced, and experimental and analytical data confirm this approach offers an effective strategy for minimizing or eliminating the efficiency losses associated with scaling MAM structures.

Adjustable sound insulation frequency band through the combination of membrane-type acoustic metamaterial array

2021 ◽  
Vol 263 (1) ◽  
pp. 5869-5877
Author(s):  
Xiang Wu ◽  
TengLong Jiang ◽  
JianWang Shao ◽  
GuoMing Deng ◽  
Chang Jin
Keyword(s):  
Thin Films ◽  
Frequency Band ◽  
Transmission Loss ◽  
Structural Parameters ◽  
Sound Insulation ◽  
Acoustic Metamaterials ◽  
Additional Mass ◽  
Acoustic Metamaterial ◽  
Material Parameters ◽  
Membrane Type

Membrane-type acoustic metamaterials are thin films or plates composed of periodic units with small additional mass. A large number of studies have shown that these metamaterials exhibit tunable anti-resonance, and their transmission loss values are much higher than the corresponding quality laws. At present, most researches on membrane-type acoustic metamaterials focus on the unit cell, and the sound insulation frequency band can only be adjusted by adjusting the structural parameters and material parameters. In this paper, two kinds of acoustic metamaterials with different structures are designed, which are the center placement of the mass and the eccentric placement of the mass.The two structures have different sound insulation characteristics. By designing different array combinations of acoustic metamaterials, the sound insulation peaks of different frequency bands are obtained. This paper studies the corresponding combination law, and effectively realizes the adjustable sound insulation frequency band.

Transmission loss of membrane-type acoustic metamaterials with coaxial ring masses

2011 ◽  
Vol 110 (12) ◽  
pp. 124903 ◽  
Author(s):  
Christina J. Naify ◽  
Chia-Ming Chang ◽  
Geoffrey McKnight ◽  
Steven Nutt
Keyword(s):  
Transmission Loss ◽  
Acoustic Metamaterials ◽  
Membrane Type

Transmission loss and dynamic response of membrane-type locally resonant acoustic metamaterials

2010 ◽  
Vol 108 (11) ◽  
pp. 114905 ◽  
Author(s):  
Christina J. Naify ◽  
Chia-Ming Chang ◽  
Geoffrey McKnight ◽  
Steven Nutt
Keyword(s):  
Dynamic Response ◽  
Transmission Loss ◽  
Acoustic Metamaterials ◽  
Membrane Type

A membrane-type acoustic metamaterial muffler

2017 ◽  
Vol 31 (08) ◽  
pp. 1750049 ◽  
Author(s):  
Fang Wang ◽  
Tianning Chen ◽  
Xiaopeng Wang ◽  
Kai Bao ◽  
Lele Wan
Keyword(s):  
Transmission Loss ◽  
Low Frequency ◽  
Acoustic Metamaterials ◽  
Acoustic Transmission ◽  
Frequency Range ◽  
Transmission Performance ◽  
Acoustic Metamaterial ◽  
Dynamic Mass ◽  
Membrane Type ◽  
Theoretical Results

Membrane-type acoustic metamaterials (MAMs) with negative dynamic mass have demonstrated the effects in the sound transmission loss (STL) at low-frequency range. This research aims to design a membrane-type acoustic metamaterial muffler (MAMM) based on the present MAMs, and to solve the problem that airflow cannot flow unimpededly in the channel once using the MAMs. For a better understanding of MAMM, the resonance frequency of the membrane was calculated and simulation was used to study the acoustic transmission performance of the MAMM. The simulation results were verified in comparison with the theoretical results of the membrane. This MAMM reduced the structural size of muffler compared with the traditional Helmholtz muffler and expand muffler, which can find application for the MAMs in acoustic absorption and noise control.

Analytical approach of membrane-type acoustic metamaterial with ring masses

2018 ◽  
Vol 14 (5) ◽  
pp. 828-836 ◽  
Author(s):  
Hongyan Tian ◽  
Ding Tong ◽  
Yourui Tao
Keyword(s):  
Analytical Approach ◽  
Transmission Loss ◽  
Low Frequency ◽  
Ring Structure ◽  
Acoustic Metamaterials ◽  
Acoustic Response ◽  
Content Type ◽  
Frequency Regime ◽  
Geometrical Effects ◽  
Membrane Type

Purpose Membrane-type acoustic metamaterials (MAMs) recently have been emerged to display useful sound attenuation properties in a low-frequency regime. The purpose of this paper is to present an analytical approach to investigate the transmission loss (TL) of a square membrane-ring structure of MAM. The geometrical effects of ring mass on the TL peak and dip frequencies of the MAM are obtained and discussed. Design/methodology/approach In this paper, based on the wave propagation and vibration theory, considering the effects of ring mass and acoustic pressure on the membrane, an analytical model is presented to analyze acoustic response of MAM. Findings Multiple peak frequencies and wide bandwidth appear in the membrane-ring structure, and they can be tuned by changing the location or numbers of the ring mass on the membrane. It is a useful method for designing such type of metamaterial. Originality/value In this paper, an analytical method is presented to evaluate the effects of ring geometric on the TL performance of square membrane-type locally resonant metamaterial. It is proved that achieving broadband and multi-peak TL profile in a single cell can indeed happen by increasing additional ring mass. The TL and frequency bandwidth can be tuned by changing the location, adding numbers and varying mass distribution of the ring masses on the membrane.

scholarly journals Structural and Acoustic Responses of a Submerged Stiffened Conical Shell

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Meixia Chen ◽  
Cong Zhang ◽  
Xiangfan Tao ◽  
Naiqi Deng
Keyword(s):  
Conical Shell ◽  
Element Model ◽  
Analytical Models ◽  
Superposition Method ◽  
Far Field ◽  
Fluid Loading ◽  
Low Frequencies ◽  
Structural Responses ◽  
The Individual ◽  
Field Sound

This paper studies the vibrational behavior and far-field sound radiation of a submerged stiffened conical shell at low frequencies. The solution for the dynamic response of the conical shell is presented in the form of a power series. A smeared approach is used to model the ring stiffeners. Fluid loading is taken into account by dividing the conical shell into narrow strips which are considered to be local cylindrical shells. The far-field sound pressure is solved by the Element Radiation Superposition Method. Excitations in two directions are considered to simulate the loading on the surface of the conical shell. These excitations are applied along the generator and normal to the surface of the conical shell. The contributions from the individual circumferential modes on the structural responses of the conical shell are studied. The effects of the external fluid loading and stiffeners are discussed. The results from the analytical models are validated by numerical results from a fully coupled finite element/boundary element model.

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