Applied Acoustics最新文献_第8页

Ultra-broadband dual-mode nonlocal sound absorber based on phase gradient Fabry-Perot slit channels 基于相位梯度法布里-珀罗狭缝通道的超宽带双模非局域吸声器

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-17 DOI: 10.1016/j.apacoust.2025.111166

Jin He, Qingxuan Liang, Dichen Li

Acoustic artificial structures have promoted the high-performance of sound absorbing devices. However, the local coupling and inherent structural losses limit the development of ultra-0broadband sound absorbing devices. Here, we propose a dual-mode nonlocal design method to improve the performance of the structure-based absorbers. By utilizing the nonlocal coupling effect caused by multiple reflections of the period phases gradient structures, the losses in the units can be amplified without extra resonance. A transverse nonlocal coupling is then excited by introducing pores in the wall of Fabry-Perot channels to enhance and transfer the internal loss. The loss power density distribution uncovers the physical mechanism of the coupling effect. A dual-mode nonlocal absorber incorporating two types of walls is designed and experimentally validated, achieving an ultra-broadband sound absorption performance from 970 Hz to 10,000 Hz with an average absorption coefficient exceeding 0.9. Our design provides a new route to improve the absorption performance of the phase gradient absorbers without considering the strong resonance of the units.

声学人工结构的发展促进了吸声装置的高性能。然而，局部耦合和固有结构损耗限制了超宽带吸声器件的发展。在此，我们提出了一种双模非局部设计方法来改善基于结构的吸波器的性能。利用周期相位梯度结构的多次反射引起的非局部耦合效应，可以在不产生额外共振的情况下放大单元中的损耗。然后通过在法布里-珀罗通道壁上引入孔隙来激发横向非局部耦合，以增强和转移内部损失。损耗功率密度分布揭示了耦合效应的物理机制。设计并实验验证了一种包含两种壁的双模非局部吸声器，实现了970 ~ 10000 Hz的超宽带吸声性能，平均吸收系数超过0.9。我们的设计为在不考虑单元强共振的情况下提高相位梯度吸收器的吸收性能提供了一条新的途径。

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引用次数: 0

The scientific works of professor Keith Attenborough 基思·阿滕伯勒教授的科学著作

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-16 DOI: 10.1016/j.apacoust.2025.111160

David L. Berry , Shahram Taherzadeh , Olga Umnova , Anton Krynkin , Kiril Horoshenkov

Prof. Attenborough’s distinguished career spans over five decades during which he has made seminal contributions to the field of physical acoustics. His extensive research encompasses acoustic propagation in and above porous media, acoustic penetration into rigid frame and poro-elastic materials, and environmental noise control. This article celebrates his work highlighting its foundational basis, scientific impact, and practical applications.

阿滕伯勒教授杰出的职业生涯跨越了50多年，在物理声学领域做出了开创性的贡献。他的研究领域包括多孔介质中的声传播、刚性框架和多孔弹性材料中的声渗透以及环境噪声控制。本文颂扬他的工作，强调其基础、科学影响和实际应用。

引用次数: 0

Comments on “Sound transmission performance of Plate-Type acoustic metamaterials for Quieter aircraft Cabins” [Appl. Acoust. 238 (2025) 110806] by Ajith A. et al 对“飞机机舱静音用板式声学超材料的传声性能”的评论[j]。声学学报，238 (2025)110806 [j]

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-15 DOI: 10.1016/j.apacoust.2025.111165

Tian Gan, Xiaole Wang, Zhenyu Huang

The recent paper “Sound Transmission Performance of Plate-Type Acoustic Metamaterials for Quieter Aircraft Cabins” (Applied Acoustics 238 (2025) 110806) investigates acoustic metamaterials for cabin noise reduction. However, several critical issues affect the validity of its conclusions. Material properties are inconsistent and sometimes incorrect and differ between simulations and experiments, undermining the validity of comparisons. The choice of the unit cell configuration as “optimal” is based solely on eigen frequency stability, without providing direct evidence of improvements in sound pressure level or sound transmission loss. Moreover, simulations apply force excitation while experiments use acoustic excitation, preventing reliable validation. Finally, several references cited cannot be retrieved from standard databases, raising concerns about their authenticity. This note highlights these issues and calls for clarification.

最近的一篇论文“用于更安静飞机客舱的板式声学超材料的传声性能”（应用声学238(2025)110806）研究了用于客舱降噪的声学超材料。然而，几个关键问题影响其结论的有效性。材料性质不一致，有时不正确，模拟和实验之间的差异，破坏了比较的有效性。选择单元格配置作为“最佳”配置仅仅是基于特征频率稳定性，而没有提供声压级或声音传输损失改善的直接证据。此外，模拟采用力激励，而实验采用声激励，妨碍了可靠的验证。最后，引用的一些参考文献无法从标准数据库中检索，这引起了对其真实性的担忧。本说明强调了这些问题，并要求澄清。

引用次数: 0

Porous sound absorbing materials from natural sources: data and modelling 天然多孔吸声材料：数据和建模

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-14 DOI: 10.1016/j.apacoust.2025.111162

Mohammad Javad SheikhMozafari , Ebrahim Taban , Keith Attenborough

This study reports porosity, flow resistivity, and normal incidence sound absorption spectra for samples fabricated from plant fibers, crushed fruit stones, chopped nut shells, and wood-cement composites. The Johnson–Champoux–Allard (JCA) model has been used to fit measured data and extract microstructural parameters such as tortuosity and characteristic lengths. An alternative, semi-analytical approach based on a model for a log normal size distribution of non-uniform cylindrical pores (NUPSD) is proposed. It uses porosity, flow resistivity, and the frequency of the first quarterwavelength resonance to estimate tortuosity. Also, it enables estimates of thermal permeability for making predictions with the Johnson-Champoux-Allard-Lafarge (JCAL) model. It avoids the need for direct fitting and provides comparable predictions. Typically, it predicts higher values of tortuosity than those resulting from fitting the JCA model. For many samples, particularly those with fibrous structure, the NUPSD-based predictions agree better with measured spectra than predictions based on JCA model fitting. The results indicate that the materials made from plant fibers are better sound absorbers than materials made from wood chips, wood cement, crushed fruit stones or chopped nut shells. Those with the higher tortuosity, implying broader pore size distributions, are more useful as sound absorbers for building applications.

本研究报告了由植物纤维、碎果核、碎坚果壳和木水泥复合材料制成的样品的孔隙度、流动电阻率和正入射声吸收光谱。Johnson-Champoux-Allard （JCA）模型用于拟合测量数据并提取微观结构参数，如扭曲度和特征长度。提出了一种基于非均匀圆柱孔隙（NUPSD）的对数正态尺寸分布模型的半解析方法。它使用孔隙度、流体电阻率和第一四分之一波长共振的频率来估计弯曲度。此外，它还可以通过Johnson-Champoux-Allard-Lafarge （JCAL）模型进行预测，从而估算热渗透率。它避免了直接拟合的需要，并提供了可比较的预测。通常，它预测的扭曲度值比拟合JCA模型的结果更高。对于许多样品，特别是那些具有纤维结构的样品，基于nupsd的预测比基于JCA模型拟合的预测更符合实测光谱。结果表明，植物纤维材料的吸声效果优于木屑、木水泥、果核碎和坚果壳碎。那些具有较高扭曲度的材料，意味着更宽的孔径分布，在建筑应用中作为吸声器更有用。

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引用次数: 0

Experimental assessment of different green wall systems: A comparative study on sound absorption and transmission loss measurements using impedance tubes 不同绿墙系统的实验评估：用阻抗管测量声吸收和传输损耗的比较研究

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-13 DOI: 10.1016/j.apacoust.2025.111159

Seda Kulak Dalkilic, Fatih Yazicioglu

This research presents a comparative acoustic analysis of green wall systems by assessing their sound absorption and transmission loss properties. A novel classification is proposed based on potential differences in acoustic behavior, encompassing direct/indirect green façades, modular living wall systems (LWS), and continuous LWS. Both single-skin and double-skin configurations were assessed to examine the effect of an air cavity. Impedance tube measurements were conducted in accordance with ISO 10534-2 and ASTM E2611-24 standards using 100 mm and 30 mm diameter tubes to cover 63–6300 Hz. Samples were prepared with Euonymus fortunei ’Emerald Gold’ as the vegetation component and tested with and without growing medium, including soil or felt. To prevent spillage, the top and bottom sides of the 3D-printed sample holders were covered with tulle fabric. Preliminary tests were conducted to assess the acoustic impact of four different tulle, identifying Z-type tulle as the most suitable due to its negligible acoustic influence and near impermeability to soil. Results indicate that modular LWS offers a superior weighted sound absorption coefficient (α_w = 0.75), particularly at low frequencies, while continuous LWS performs better in terms of weighted sound reduction index (R_w = 16 dB). Green façade systems, by contrast, exhibited the lowest performance in both metrics. The addition of an air cavity (double-skin setup) generally enhanced acoustic behavior, especially for low-frequency absorption. These findings offer evidence-based guidance for the integration of green wall systems in urban environments where both aesthetic and noise-control functions are desired.

本研究通过评估绿色墙体系统的吸声和传声损失特性，提出了一种比较声学分析方法。基于声学行为的潜在差异，提出了一种新的分类方法，包括直接/间接绿色墙、模块化生物墙系统（LWS）和连续生物墙系统。评估了单皮和双皮配置，以检查空腔的影响。阻抗管测量按照ISO 10534-2和ASTM E2611-24标准进行，使用100毫米和30毫米直径的管，覆盖63-6300赫兹。以黄羽卫矛“祖母绿金”为植物成分制备样品，并在土壤或毛毡等生长介质下和在无生长介质下进行试验。为了防止溢出，3d打印样品支架的上下两侧都覆盖了薄纱织物。进行了初步试验，以评估四种不同薄纱的声学影响，确定z型薄纱是最合适的，因为它的声学影响可以忽略，对土壤几乎不透水。结果表明，模块化LWS具有更好的加权吸声系数（αw = 0.75），特别是在低频时，而连续LWS在加权减声指数方面表现更好（Rw = 16 dB）。相比之下，绿色农业系统在这两个指标上表现最差。增加一个空腔（双蒙皮设置）通常增强声学性能，特别是低频吸收。这些发现为在城市环境中整合绿色墙体系统提供了基于证据的指导，在城市环境中既需要美学功能，又需要噪声控制功能。

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引用次数: 0

Efficient finite difference modeling of infrasound propagation in realistic 3D domains: Validation with wind turbine measurements 次声传播在现实三维域的有效有限差分建模：与风力涡轮机测量验证

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-12 DOI: 10.1016/j.apacoust.2025.111156

Ken Mattsson , Gustav Eriksson , Leif Persson , José Chilo , Kourosh Tatar

We present a high-fidelity simulation tool for accurate acoustic modeling across a wide range of applications. The numerical method is based on diagonal-norm Summation-By-Parts (SBP) finite-difference operators, which guarantee linear stability on piecewise curvilinear multi-block grids. Realistic three-dimensional atmospheric and topographic data are directly incorporated into the simulations, and the solver is implemented in CUDA to achieve high computational efficiency. Verification is performed through convergence studies against highly resolved benchmark problems in both two and three spatial dimensions, while validation is carried out using high-quality infrasound measurements from two modern wind farms in Sweden. The results show that modern, large-scale wind turbines generate infrasound levels significantly higher than those reported for older, smaller turbines. These findings advance the understanding of the acoustic characteristics of contemporary wind turbines and provide important guidance for assessing their potential environmental and societal impacts.

我们提出了一种高保真仿真工具，用于广泛应用的精确声学建模。该数值方法基于对角范数分段求和（SBP）有限差分算子，保证了分段曲线多块网格上的线性稳定性。模拟中直接引入了真实的三维大气和地形数据，求解器在CUDA中实现，计算效率高。通过对二维和三维空间高度解决的基准问题的收敛研究进行验证，同时使用瑞典两个现代风电场的高质量次声测量进行验证。结果表明，现代大型风力涡轮机产生的次声水平明显高于报道的老式小型涡轮机。这些发现促进了对当代风力涡轮机声学特性的理解，并为评估其潜在的环境和社会影响提供了重要的指导。

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引用次数: 0

Brain activity and restorative effects of birdsong at different sound pressure levels: An electroencephalographic study 不同声压水平下鸟鸣的脑活动和恢复作用：脑电图研究

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-11 DOI: 10.1016/j.apacoust.2025.111155

Xiaotong Jing , Chao Liu , Jiaxin Li , Weijun Gao , Hiroatsu Fukuda

Natural soundscapes with birdsong provide significant psychological advantages. However, the psychophysiological mechanisms behind these effects at different sound pressure levels (SPLs) remain unclear. This study investigated the restorative effects of birdsong at five SPLs—40, 45, 50, 55, and 60 dB(A)—using the Perceived Restorativeness Scale (PRS) and electroencephalography (EEG) with 30 participants. Subjective evaluations identified 45 dB(A) as optimal for stress relief, with PRS total scores increasing by 0.97–1.62 compared to silent (40 dB(A)) and higher (55–60 dB(A)) SPLs. Fascination and compatibility scores declined significantly above 55 dB(A). Physiologically, birdsong at 45–50 dB(A) enhanced alpha wave activity by 14.1 %, relative to the 40 dB(A) condition, indicating mental relaxation. In contrast, 60 dB(A) increased EEG mental stress by 29 %. Event-related potential (ERP) analysis revealed that 40–50 dB(A) range strongly activated the P300 component, with average amplitudes of 0.15–0.29 μV at the Pz channel, reflecting a higher relation. The LPP component attained its average amplitude (0.14 μV) in the Pz channel under 60 dB(A), indicating intensified emotional processing associated with stress. This activation pattern demonstrated that the stress recovery process engaged activity in the brain’s parietal lobe. A Random Forest model using ERP features achieved 71.4 % classification accuracy, confirming the utility of ERP as a physiological indicator. Polynomial regression identified 53.6 dB(A) as the upper SPL threshold for restorative benefits. These findings offer a scientific basis for designing restorative sound environments and highlight ERP analysis as an effective tool for evaluating natural soundscapes.

鸟鸣的自然声景提供了显著的心理优势。然而，不同声压级（SPLs）下这些效应背后的心理生理机制尚不清楚。采用感知恢复性量表（PRS）和脑电图（EEG）对30名被试在40、45、50、55和60 dB(A) 5种声压下鸟鸣的恢复性效果进行了研究。主观评价表明，45 dB(A)是缓解压力的最佳选择，与沉默（40 dB(A)）和更高（55-60 dB(A)）的SPLs相比，PRS总分增加了0.97-1.62。魅力和相容性评分在55 dB(A)以上显著下降。在生理上，相对于40 dB(A)的条件，45-50 dB(A)的鸟鸣声使α波活动增强14.1%，表明精神放松。相比之下，60 dB(A)使脑电图精神应激增加29%。事件相关电位（ERP）分析表明，在40 ~ 50 dB(A)范围内P300分量被强烈激活，Pz通道的平均振幅为0.15 ~ 0.29 μV，反映出较高的相关性。在60 dB(A)下，LPP分量在Pz通道的平均振幅为0.14 μV，表明应激相关的情绪加工加剧。这种激活模式表明，应激恢复过程涉及大脑顶叶的活动。使用ERP特征的随机森林模型实现了71.4%的分类准确率，证实了ERP作为生理指标的实用性。多项式回归确定53.6 dB(A)为恢复效益的最高声压级阈值。这些发现为恢复性声环境的设计提供了科学依据，并突出了ERP分析作为评价自然声景观的有效工具。

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引用次数: 0

Socio-acoustic survey on railway noise before and after the step changes in noise exposure and earthquakes in Kumamoto, Japan 日本熊本地区铁路噪声暴露与地震阶跃变化前后的社会声学调查

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-11 DOI: 10.1016/j.apacoust.2025.111157

Takashi Morihara , Koji Shimoyama , Shigenori Yokoshima , Makoto Morinaga , Sohei Tsujimura , Yasuhiro Hiraguri , Yasuhiro Murakami , Takashi Yano

The Kyushu Shinkansen Line was fully opened in 2011. The elevation of the conventional railway line was completed in the northern area of Kumamoto Station, and a new station began operation in the southern area in March 2016. Severe earthquakes struck the Kumamoto area in April 2016. Socio-acoustic surveys on community responses to railway noise and vibration were conducted before and after the interventions and the earthquakes. As a result, annoyance decreased after the earthquakes for residents in detached houses in the north, but increased for apartment residents in the north and both detached and apartment residents in the south. This was attempted to be explained using cognitive biases and the World Health Organization’s four levels of health in the field of sanitation. The use of trains and the frequency of opening and closing windows significantly affected annoyance for detached house residents in the northern area, while earthquake damage affected apartment residents in both areas. This suggests that the annoyance profile depends on the area’s characteristics and housing type.

九州新干线于2011年全面开通。熊本站北部地区的常规铁路线的标高已经完成，2016年3月，南部地区的新站开始运营。2016年4月，熊本地区发生强烈地震。在干预措施和地震发生前后，对社区对铁路噪声和振动的反应进行了社会声学调查。结果，地震后北部独栋住宅居民的烦恼有所减少，但北部公寓居民和南部独栋公寓居民的烦恼有所增加。有人试图用认知偏差和世界卫生组织在卫生领域的四个健康等级来解释这一点。火车的使用和开窗和关窗的频率显著影响了北部地区独立式住宅居民的烦恼，而地震破坏影响了这两个地区的公寓居民。这表明，烦恼的概况取决于该地区的特点和住房类型。

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引用次数: 0

Modelling and experimental investigation of multilayered nonwoven-microperforated foil hybrid panels for advanced sound attenuation 多层非织造布微孔箔复合板超前消声性能的建模与实验研究

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-10 DOI: 10.1016/j.apacoust.2025.111158

Siddhi Vardhan Singh Rao , Apurba Das , Bipin Kumar , Nandan Kumar

This study investigates the acoustic performance of singular and multilayered nonwoven absorbers, with particular emphasis on the integration of flexible aluminium microperforated foils (MPFs). Experimental testing combined with empirical modelling was employed to characterise their sound absorption behaviour. For acoustic behaviour of multilayered nonwoven configurations, homogenised equivalent-fluid modelling was developed with optimising the power-law constants using particle swarm optimization (PSO) algorithm. The results demonstrate that increasing the number of layers, while maintaining constant thickness or areal density, enhances sound absorption due to viscous, thermal, and structural losses, as well as phase shift and impedance matching between intermediate air layers. Compression of multilayered structures was found to reduce internal air cavities, leading to diminished absorption and a shift of peak performance toward higher frequencies. The incorporation of MPFs, engineered with structural damping and mass end correction modification to Maa’s model, yielded significant enhancement in low- and mid-frequency absorption. Moreover, the placement and number of MPFs within multilayer assemblies were shown to modulate both the magnitude and frequency of peak absorption. These findings provide valuable insights for designing advanced insulation materials that combine thermal management with improved acoustic comfort in automotive, industrial, and building applications.

本研究探讨了单层和多层非织造吸声材料的声学性能，特别强调了柔性铝微穿孔箔（mpf）的集成。采用实验测试和经验建模相结合的方法对其吸声特性进行了表征。针对多层非织造布结构的声学特性，采用粒子群优化（PSO）算法对幂律常数进行优化，建立了均匀等效流体模型。结果表明，在保持厚度或面密度不变的情况下，增加层数可以增强由于粘滞、热损失和结构损失引起的声吸收，以及中间空气层之间的相移和阻抗匹配。多层结构的压缩被发现减少了内部空腔，导致吸收减少和峰值性能向更高频率的转移。MPFs结合结构阻尼和Maa模型的质量端修正，显著增强了低频和中频吸收。此外，多层组件内mpf的位置和数量显示调制峰值吸收的幅度和频率。这些发现为设计先进的隔热材料提供了有价值的见解，这些材料将热管理与改善汽车、工业和建筑应用中的声学舒适性相结合。

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引用次数: 0

Low-frequency broadband acoustic ventilation metamaterial via cascaded massless-membrane-integrated Helmholtz resonators 通过级联无质量膜集成亥姆霍兹谐振器的低频宽带声通风超材料

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2025-11-08 DOI: 10.1016/j.apacoust.2025.111152

Xiaodong Zhang , Jing Nie , Yang Liu , Fengbin Lin , Jinhong He , Rui Yang , Huiyong Yu

Noise generated by pipelines poses a critical challenge to ensuring passenger comfort in transportation systems. Conventional noise control devices inherently face a trade-off between noise attenuation performance and ventilation efficiency. To address this challenge, this study presents a ventilated acoustic metamaterial that combines a massless, stress-free thermoplastic polyurethane (TPU) membrane with cascaded Helmholtz resonator (membrane-cascaded HR). By modulating the membrane’s placement within the membrane-cascaded HR cavity, the structure enables frequency tuning without altering unit dimensions, thus facilitating efficient noise mitigation in confined geometries. Finite element simulations and experimental results validate that the proposed membrane-cascaded HR group achieves a broadband sound transmission loss (STL) exceeding 10 dB in the low frequency range. Remarkably, the compact membrane-cascaded HR group features sub-wavelength dimensions and exceptional parametric stability. Composed of seven units, it maintains robust performance under 30 % variations in TPU membrane Young’s modulus (14–20 MPa). Experimental validations in both straight and curved ducts confirm consistent frequency-selective attenuation performance. This work offers a practical approach for mitigating low-frequency noise in ventilation systems.

管道产生的噪声对交通系统中乘客的舒适性提出了严峻的挑战。传统的噪声控制设备固有地面临着噪声衰减性能和通风效率之间的权衡。为了应对这一挑战，本研究提出了一种通风声学超材料，该材料将无质量、无应力的热塑性聚氨酯（TPU）膜与级联亥姆霍兹谐振器（膜级联HR）结合在一起。通过调节膜在膜级联HR腔内的位置，该结构可以在不改变单元尺寸的情况下进行频率调节，从而在受限的几何形状中有效地降低噪声。有限元模拟和实验结果验证了所提出的膜级联HR组在低频范围内实现了超过10 dB的宽带声传输损失（STL）。值得注意的是，紧凑的膜级联HR基团具有亚波长尺寸和优异的参数稳定性。它由7个单元组成，在TPU膜杨氏模量（14-20 MPa）变化30%的情况下仍能保持强劲的性能。在直线和弯曲管道中的实验验证证实了一致的频率选择衰减性能。这项工作为减轻通风系统中的低频噪声提供了一种实用的方法。

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引用次数: 0