A Fano-based acoustic metamaterial for ultra-broadband sound barriers

Ultra-broadband sound reduction schemes covering living and working noise spectra are of high scientific and industrial significance. Here, we report, both theoretically and experimentally, on an ultra-broadband acoustic barrier assembled from space-coiling metamaterials (SCMs) supporting two Fano resonances. Moreover, acoustic hyper-damping is introduced by integrating additional thin viscous foam layers in the SCMs for optimizing the sound reduction performance. A simplified model is developed to study sound transmission behaviour of the SCMs under a normal incidence, which sets forth the basis to understand the working mechanism. An acoustic barrier with 220 mm thickness is then manufactured and tested to exhibit ultra-broadband transmission loss overall above 10 dB across the range 0.44–3.85 kHz, covering completely nine third-octave bands. In addition, unconventional broadband absorption in the dampened barrier (65%) is experimentally observed as well. We believe this work paves the way for realizing effective broadband sound insulation, absorption and sound wave controlling devices with efficient ventilation.

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

INTER-NOISE and NOISE-CON Congress and Conference Proceedings ◽

10.3397/in-2021-3472 ◽

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.

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A composite and deformable honeycomb acoustic metamaterial

International Journal of Modern Physics B ◽

10.1142/s0217979218502041 ◽

2018 ◽

Vol 32 (20) ◽

pp. 1850204 ◽

Cited By ~ 26

Author(s):

Nansha Gao ◽

Hong Hou ◽

Jiu Hui Wu

Keyword(s):

Transmission Loss ◽

Tensile Deformation ◽

Ethylene Vinyl Acetate ◽

Sound Insulation ◽

Frequency Range ◽

Low Frequencies ◽

Acoustic Metamaterial ◽

Copolymer Films ◽

Insulation Effect ◽

Experiment Analysis

This paper reports the design of a deformable honeycomb acoustic metamaterial, which consists of honeycomb structures and ethylene-vinyl acetate (EVA) copolymer films stacked on each other. The FEA results agree well with the experiment analysis, and it is proved that the proposed structure can break the acoustic mass law below 1000 Hz. This paper reveals that dislocation, compression, and tensile deformation can regulate the sound transmission loss (STL) in a wider frequency range. It is concluded that the STL of a bilayer structure is, on average, 10 dB higher than that of a monolayer structure at low-frequencies. When the dislocation distance b = 1.5 mm, the corresponding STLs reach their maximum values. The FEA and experiment results prove that compression and tensile deformation can considerably improve the sound insulation effect. Such a deformable honeycomb acoustic metamaterial with high STL provides a new concept for engineering noise control.

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Low-Frequency Broadband Sound Transmission Loss of Infinite Orthogonally Rib-Stiffened Sandwich Structure with Periodic Subwavelength Arrays of Shunted Piezoelectric Patches

Shock and Vibration ◽

10.1155/2017/2791351 ◽

2017 ◽

Vol 2017 ◽

pp. 1-17 ◽

Cited By ~ 1

Author(s):

Zhifu Zhang ◽

Weiguang Zheng ◽

Qibai Huang

Keyword(s):

Sandwich Structure ◽

Transmission Loss ◽

Virtual Work ◽

Low Frequency ◽

Sound Transmission ◽

Sound Insulation ◽

Convergence Criterion ◽

Sound Transmission Loss ◽

Space Harmonic ◽

Broadband Sound

This paper studies low-frequency sound transmission loss (STL) of an infinite orthogonally rib-stiffened sandwich structure flexibly connected with periodic subwavelength arrays of finite shunted piezoelectric patches. A complete theoretical model is proposed by three steps. First, the panels and piezoelectric patches on both sides are equivalent to two homogeneous facesheets by effective medium method. Second, we take into account all inertia terms of the rib-stiffeners to establish the governing equations by space harmonic method, separating the amplitude coefficients of the equivalent facesheets through virtual work principle. Third, the expression of STL is reduced. Based on the two prerequisites of subwavelength assumption and convergence criterion, the accuracy and validity of the model are verified by finite element simulations, cited experiments, and theoretical values. In the end, parameters affecting the STL performance of the structure are studied. All of these results show that the sandwich structure can improve the low-frequency STL effectively and broaden the sound insulation bandwidth.

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IMPLEMENTATION OF LABORATORY MEASUREMENT OF AIRBORNE SOUND INSULATION BASED ON ISO AND ASTM STANDARDS IN NATIONAL STANDARDIZATION AGENCY OF INDONESIA (BSN)

Jurnal Standardisasi ◽

10.31153/js.v23i1.861 ◽

2021 ◽

Vol 23 (1) ◽

pp. 77

Author(s):

Bondan Dwisetyo ◽

Maharani Ratna Palupi ◽

Fajar Budi Utomo ◽

Chery Chaen Putri ◽

Dodi Rusjadi ◽

...

Keyword(s):

Transmission Loss ◽

Laboratory Measurement ◽

Sound Insulation ◽

Reference Curve ◽

Airborne Sound ◽

Significant Difference ◽

Single Number ◽

Sound Reduction ◽

Reduction Index

<p>The implementation of laboratory measurement of airborne sound insulation based on ISO and ASTM standards was carried out at SNSU BSN. The aim of this work to realize the measurement of airborne sound insulation for several sample tests, where the procedure of the test is performed according to the updated standard ISO 10140 and ASTM E90. Besides, the single number rating also is determined based on ISO 717-1 and ASTM E413. This measurement has been conducted in the two reverberation rooms using pressure method consist of measuring the sound pressure level, measuring the reverberation time, obtaining the sound reduction index (R) or sound transmission loss (STL), and determination of a single-number ratings of the samples test. From the results, some parameter requirements such as the frequency range and the rounding procedure of R or STL influence the measurement result slightly. Subsequently, the significant difference is obtained for the determination of single number rating in the shifting procedure of the reference curve.</p>

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An improved approach for normal-incidence sound transmission loss measurement using a four-microphone impedance tube

Journal of Vibration and Control ◽

10.1177/1077546320926905 ◽

2020 ◽

pp. 107754632092690

Author(s):

Zechao Li ◽

Sizhong Chen ◽

Zhicheng Wu ◽

Lin Yang

Keyword(s):

Transfer Matrix ◽

Sound Absorption ◽

Transmission Loss ◽

Sound Transmission ◽

Normal Incidence ◽

Sound Insulation ◽

Sound Transmission Loss ◽

The Common ◽

Wavefield Decomposition ◽

Insulation Performance

The main aim of this study is to introduce an improved method for determining the sound properties of acoustic materials which is more precise than the common wavefield decomposition method and simpler than the common transfer matrix method. In the first part of the article, a group of formulae for calculating sound transmission loss is represented by combining the wavefield decomposition and transfer matrix methods. Subsequently, a formula for calculating sound absorption coefficients is derived from these formulae by definition. Furthermore, the present formulae are validated by comparing the experimental results achieved with the present formulae and those results obtained by other methods recorded in published articles. Eventually, it is demonstrated that the method can accurately measure the sound insulation performance of materials and the sound absorption properties of limp and lightweight materials.

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Ultra-thin composite underwater honeycomb-type acoustic metamaterial with broadband sound insulation and high hydrostatic pressure resistance

Composite Structures ◽

10.1016/j.compstruct.2021.114603 ◽

2021 ◽

pp. 114603

Author(s):

Haibin Zhong ◽

Yongjun Tian ◽

Nansha Gao ◽

Kuan Lu ◽

Jiuhui Wu

Keyword(s):

Hydrostatic Pressure ◽

High Hydrostatic Pressure ◽

Sound Insulation ◽

Acoustic Metamaterial ◽

Pressure Resistance ◽

Broadband Sound

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Broadband sound transmission loss of a large-scale membrane-type acoustic metamaterial for low-frequency noise control

Applied Physics Letters ◽

10.1063/1.4995405 ◽

2017 ◽

Vol 111 (4) ◽

pp. 041903 ◽

Cited By ~ 17

Author(s):

Linus Yinn Leng Ang ◽

Yong Khiang Koh ◽

Heow Pueh Lee

Keyword(s):

Large Scale ◽

Noise Control ◽

Transmission Loss ◽

Low Frequency ◽

Frequency Noise ◽

Sound Transmission Loss ◽

Low Frequency Noise ◽

Acoustic Metamaterial ◽

Membrane Type ◽

Broadband Sound

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Broadband ventilated metamaterial silencer for high reflection based on Fano-like interference

International Journal of Modern Physics B ◽

10.1142/s0217979221500879 ◽

2021 ◽

Vol 35 (06) ◽

pp. 2150087

Author(s):

Quanyuan Jiang ◽

Xiaopeng Wang ◽

Yanhui Xi ◽

Weikang Huang ◽

Tianning Chen

Keyword(s):

Transmission Loss ◽

Sound Insulation ◽

Sound Waves ◽

Asymmetric Transmission ◽

Acoustic Performance ◽

Free Air ◽

Potential Applications ◽

Parametric Studies ◽

Broadband Sound ◽

High Reflection

Conventional sound shielding structures is difficult to meet the requirements of low-to-middle frequency broadband sound insulation and free ventilation. In this paper, we propose a ventilated metamaterial silencer based on Fano-like interference, which can achieve the sound transmission loss (STL) of more than 10 dB in the range of 516–970 Hz with subwavelength thickness (0.11 [Formula: see text]) while remains an opening area ratio of 23%. The designed silencer is composed of a large central orifice and four surrounding coiling channels, making the sound waves passing through the two areas generate Fano-like asymmetric transmission spectrum and form efficient reflection to insulate sound coming from various directions. The parametric studies are also carried out to investigate the tunable acoustic performance. Experiment measurement matches well with the simulation results. In the future, the proposed silencer may have potential applications in practical environments requiring broadband sound insulation and free air flows.

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Transmission Loss of Membrane-Type Acoustic Metamaterial with Negative Effective Mass

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.1749 ◽

2017 ◽

Vol 898 ◽

pp. 1749-1756 ◽

Cited By ~ 1

Author(s):

Guo Chang Lin ◽

Song Qiao Chen ◽

Yu Liang Li ◽

Hui Feng Tan

Keyword(s):

Effective Mass ◽

Transmission Loss ◽

Mass Density ◽

Small Mass ◽

Equivalent Model ◽

Sound Insulation ◽

Rubber Membrane ◽

Acoustic Metamaterial ◽

Spring Force ◽

Membrane Type

The transmission loss (TL) of membrane-type acoustic metamaterials consisting of small mass and rubber membrane was studied. By establishing a mass-spring equivalent model of metamaterial structural unit, which regards rubber membrane as having the dual role of damping force and spring force, we demonstrated that effective mass density of this membrane-type acoustic metamaterial was negative in the band gap range by theoretical analysis. Based on the theory of plane wave propagation, we studied the sound insulation of this membrane-type acoustic metamaterial. The result showed that membrane-type metamaterial was based on the principle of dipole resonance, which made the membrane-type acoustic metamaterial appear high reflection and low transmission phenomenon so as to achieve the aim of reducing noise. By optimal design, the sound attenuation frequency range of this membrane-type acoustic metamaterial was reduced to 20Hz-100Hz, greatly enhancing the ability of this metamaterial in terms of low-frequency sound insulation. We obtained the distribution of sound intensity at the optimum transmission frequency and the best reflection frequency by coupled acoustic-structural analysis. The best sound insulation frequency was matched with the second order and the third order eigenfrequency of this membrane-type acoustic metamaterial unit, and the strain energy was concentrated at the joint of small mass and the membrane. The total sound insulation of acoustic metamaterial plate was better than the single metamaterial unit.

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