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Composite acoustic system for low-frequency sound absorption [PDF]
Scientific ReportsAbsorption of low-frequency sound is a difficult engineering problem because long-wave sound energy is poorly dissipated. Traditional sound absorbing materials such as porous materials, microperforated sheets or sound absorbing wedges have a poor low ...
Eulalia Gliścińska, Marina Michalak
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Barrier-free duct muffler for low-frequency sound absorption
Frontiers in Materials, 2022 We demonstrate a duct muffler design that operates in the low-frequency range (<2000 Hz). The device contained a pair of coupled annular Helmholtz resonators (HRs) and porous material stuffing. HRs were installed as side branches of a circular tube to
Cong Gao +8 more
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Absorption of Broadband Low‐Frequency Sound Beyond the Thermodynamics Limit: An Acoustic Resonator With Magnetic Bearing [PDF]
Advanced ScienceThis study reports the first experimental realization of magnetic negative stiffness to achieve a significant net gain in broadband, low‐frequency sound absorption, beyond the thermodynamic limit posed by the relative incompressibility of cavity fluid at
Ying Hu +5 more
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Sound absorption properties for multi-layer of composite materials using nonwoven fabrics with kapok
Journal of Industrial Textiles, 2022 Kapok fiber with high degree of hollow and small fiber diameter has excellent sound absorption. To optimize the sound absorption characters at the low frequency, sound absorption coefficients and specific surface impedance of two-layer, three-layer, and ...
Xueting Liu +2 more
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Sound absorption performance of helically perforated porous metamaterials at high temperature
Materials & Design, 2023 A high-temperature theoretical model is established to investigate the sound absorption performance of helically perforated porous metamaterials (HPPM) at high temperature. Finite element simulations are carried out to validate the theoretical model, and
Weitao Zhang, Xuewei Liu, Fengxian Xin
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A hybrid acoustic structure for low-frequency and broadband underwater sound absorption
Journal of Low Frequency Noise, Vibration and Active Control, 2022 The underwater anechoic coating with local resonant units is an effective method to achieve low-frequency sound absorption. However, the structure obtained in this way is not satisfactory in the sound absorption effect of mid-high frequency bands ...
Xinyu Jia +4 more
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Journal of Low Frequency Noise, Vibration and Active Control, 2021 The low-frequency harmonic components of urban substation noise are easy to annoy the residents. Multi-frequency perfect sound-absorbing metasurface based on the Helmholtz resonator (HR) is an alternative solution to suppress the low-frequency harmonic ...
Sun Wei +4 more
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Acoustic Characterization of Sugarcane Bagasse Particleboard Panels (Saccharum officinarum L) [PDF]
Materials Research, 2015 The use of sugarcane bagasse minimizes the environmental impact and contributes to the creation of a new product with low density, good sound absorption capacity and can improve the acoustic conditions of buildings.
Sylvia Thais Martins Carvalho +5 more
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Journal of Low Frequency Noise, Vibration and Active Control, 2022 Since the development of advanced sound absorption material is highly critical in noise control applications, anechoic coatings, and acoustic metamaterials, both fabrication technology and structure design are significant in the achievement of broadband ...
Longgui Peng +4 more
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Advances in Mechanical Engineering, 2022 A coiled Helmholtz cavity acoustic metamaterial structure, which consists of three perforated plates, two channel layers and an air back cavity, is designed to address the problem of poor absorption of low-frequency band noise by conventional acoustic ...
Hongyu Cui, Zhaoping Hu, Haoming Hu
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