Applied Acoustics最新文献_第2页

A ventilated silencer based on rainbow trapping structure for broadband noise attenuation 一种基于彩虹俘获结构的宽带降噪通风消声器

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-23 DOI: 10.1016/j.apacoust.2026.111240

Yunwei Chen , Xiaomei Xu , Kangfan Yu , Qidi Fu , Xiaofei Du , Jianrun Zhang

Fan noise propagating within ducts is typically broadband in nature. Conventional silencers often fail to achieve effective broadband noise insulation, presenting a persistent challenge in engineering applications. The rainbow trapping effect offers an innovative solution to this problem. This paper proposes a ventilated silencer based on the rainbow trapping effect, which provides broadband capability of noise attenuation without altering the duct inner diameter. The original rainbow trapping structure is transformed into a fan shaped configuration, mounted by circular arrays and filled with porous materials to form a silencer suitable for duct applications. To analyze the performance of this silencer, a comprehensive finite element model is developed, which is validated through impedance tube experiments. The results reveal that sound waves with different frequencies could be captured by branch cavities with varying depths, and the acoustic energy will be subsequently dissipated by the filled porous materials. Both impedance tube experimental and simulation results demonstrate the broadband performance of the proposed silencer, specifically achieving a sound transmission loss exceeding 10 dB above 257 Hz, representing 90% acoustic energy insulation. Fan tests demonstrated that the average overall sound pressure level is reduced by 4.8 dB after installing the silencer. Parametric analysis indicates that this silencer can achieve excellent broadband performance without requiring complicated design and manufacturing processes. This work presents a promising approach for duct and fan noise control applications.

在管道内传播的风扇噪声本质上是典型的宽带噪声。传统的消声器往往不能实现有效的宽带噪声隔离，这在工程应用中提出了一个持续的挑战。彩虹诱捕效应为这个问题提供了一个创新的解决方案。本文提出了一种基于彩虹诱捕效应的通风消声器，在不改变管道内径的情况下提供宽带降噪能力。原来的彩虹诱捕结构被改造成扇形结构，由圆形阵列安装，并填充多孔材料，形成适合管道应用的消声器。为了分析该消声器的性能，建立了综合有限元模型，并通过阻抗管实验进行了验证。结果表明，不同深度的分支腔可以捕获不同频率的声波，而声波能量随后会被填充的多孔材料耗散。阻抗管实验和仿真结果均证明了所提出的消声器的宽带性能，特别是在257 Hz以上的声音传输损失超过10 dB，代表90%的声能绝缘。风扇测试表明，安装消声器后，平均总声压级降低了4.8 dB。参数分析表明，该消声器无需复杂的设计和制造工艺，即可获得优异的宽带性能。这项工作为风管和风机噪声控制应用提供了一种有前途的方法。

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引用次数: 0

Spatial correlation of non-uniform seafloor vibrations under a marine isotropic noise field 海洋各向同性噪声场下非均匀海底振动的空间相关性

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-19 DOI: 10.1016/j.apacoust.2026.111236

Bowen Dong, Haifeng Zhang, Fengyuan Yang

This paper addresses the spatial correlation modeling of seafloor sediment–water interface vibrations within an isotropic noise field. The novelty of this work lies in revealing the role of non-uniform waves in shaping the spatial correlation of interface vibrations, establishing a theoretical framework for the biphasic half-space interface under isotropic noise, and deriving integral expressions for the auto- and cross-correlations of interface vibrations. The correlation behavior of sediment–water interface vibrations is analyzed, considering various influencing factors, including the properties of the sediment layer and the noise frequency. The study demonstrates that non-uniform waves at the interface significantly influence the spatial cross-correlation of vibrations. These waves induce spatial correlation among the originally uncorrelated tri-axial vibrations of the sediment–water interface.

本文研究了各向同性噪声场下海底沉积物-水界面振动的空间相关模型。本工作的新颖之处在于揭示了非均匀波在形成界面振动空间相关性中的作用，建立了各向同性噪声下双相半空间界面的理论框架，并推导了界面振动的自相关和互相关的积分表达式。分析了沉积物-水界面振动的相关行为，考虑了各种影响因素，包括沉积物层的性质和噪声频率。研究表明，界面处的非均匀波对振动的空间相互关系有显著影响。这些波引起了原本不相关的沉积物-水界面三轴振动之间的空间相关性。

引用次数: 0

Acoustic alerting system for electric vehicles combining directional sound technique with object tracking—towards quieter urban environments 结合定向声技术和目标跟踪的电动汽车声报警系统——面向更安静的城市环境

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-17 DOI: 10.1016/j.apacoust.2026.111231

Hui Li , Ling Zheng , Jun Wu , Jian Pang

Electric vehicles (EVs) are mandated to emit warning sounds to notify pedestrians. However, it is desirable that these warning sounds are directed precisely to vulnerable road-users, thereby avoiding unnecessary noise pollution. This paper integrates directional sound technology with object-tracking in artificial Acoustic Vehicle Alerting Systems (AVAS) for electric vehicles. Directional sound is achieved using a loudspeaker array. Real-time locations of road users are accomplished via the vehicle-mounted surround-view cameras. They are integrated to generate a sound field that can adjust its direction in real-time according to the positions of moving road-users. This system supports seven operating cases, including multiple road users in the left, middle, right, left-middle, left–right and right-middle zones of the vehicle, plus the scenario of full vehicle surrounding by road users. Offline simulations and laboratory experiments validated the AVAS effectiveness, showing that the adaptive AVAS can produce targeted directional sound fields within a small angular region, dynamically track moving objects to adjust sound orientation in real time, and cut non-target noise by over 15 dB. In areas distant from moving objects, the warning sound remains at relatively low levels. By reducing unnecessary warning sound in non-critical areas, the proposed adaptive AVAS enhances the environmental performance of EVs and contributes to quieter urban environments.

电动汽车（ev）必须发出警告声音，以提醒行人。然而，最好这些警告声音是针对脆弱的道路使用者，从而避免不必要的噪音污染。本文将定向声技术与目标跟踪技术相结合，应用于电动汽车人工声车辆报警系统。定向声音是通过扬声器阵列来实现的。道路使用者的实时定位是通过车载环视摄像头完成的。它们被整合在一起，产生一个声场，可以根据移动的道路使用者的位置实时调整其方向。该系统支持车辆左、中、右、左中、左右、右中、右中、右中、右中等多个道路使用者，以及道路使用者全车环绕场景等7种操作场景。离线仿真和室内实验验证了AVAS的有效性，结果表明，自适应AVAS能够在小角度区域内产生目标定向声场，动态跟踪运动目标实时调整声向，并能有效降低非目标噪声15 dB以上。在远离移动物体的区域，警告声音保持在相对较低的水平。通过减少非关键区域不必要的警告声音，所提出的自适应AVAS提高了电动汽车的环保性能，有助于营造更安静的城市环境。

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引用次数: 0

An empirical diffusion coefficient function for the acoustic diffusion equation model in long rooms 长室声扩散方程模型的经验扩散系数函数

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-16 DOI: 10.1016/j.apacoust.2026.111234

Ilaria Fichera, Cédric Van hoorickx, Maarten Hornikx

In the diffusion equation model, the diffusion coefficient quantifies the relationship between the sound intensity and the gradient of the sound energy density. It is a crucial factor that affects the diffusion equation model, mostly for non-proportionate rooms. Previous work has indicated that this parameter varies spatially based on the rooms’ dimensions, the absorption coefficient, and the distance between source and receiver positions. In this paper, the spatially dependent diffusion coefficient is obtained by optimizing a distance-dependent function for the diffusion coefficient using reference results obtained from the radiosity method. The estimated diffusion coefficient inside long rooms is also shown to depend on the source position. The empirical function for the diffusion coefficient for long rooms is established as a quadratic polynomial function and is applicable for elongated rooms with a constant absorption coefficient lower than 0.3 and a minimum cross section of 4 m².

在扩散方程模型中，扩散系数量化了声强与声能密度梯度之间的关系。它是影响扩散方程模型的一个关键因素，尤其是对于非比例房间。先前的研究表明，该参数在空间上的变化取决于房间的尺寸、吸收系数以及源和接收器位置之间的距离。本文利用辐射度法得到的参考结果，通过优化扩散系数的距离相关函数，得到空间相关的扩散系数。估计的扩散系数在长房间也显示依赖于源的位置。建立长房间扩散系数的经验函数为二次多项式函数，适用于吸收系数恒定小于0.3、最小截面为4 m2的细长房间。

引用次数: 0

Investigation on the acoustic interaction between over-the-stator liner and stator blade row 过静叶衬板与静叶排间声学相互作用研究

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-14 DOI: 10.1016/j.apacoust.2026.111232

Chuanyang Liu , Xiaoyu Wang , Guangyu Zhang , Zhiliang Hong , Xiaofeng Sun

To investigate the noise reduction characteristics of a liner located at the blade tip on incident sound waves, this study combines experimental and numerical methods to explore the acoustic interaction mechanism between incident sound waves, the over-the-stator liner (OTSL), and the blade row under flow-free conditions. Experimental comparisons among the OTSL (with blade row), the liner only (no blade row), and the blade row only (with a hard wall casing) configurations reveal that the blade row significantly affects the liner’s noise reduction performance, and the OTSL exhibits effective sound absorption for both transmitted and scattered sound waves. Overall, the noise reduction effectiveness of the OTSL is superior to that of the liner only. Numerical analyses of acoustic particle velocity on the liner surface and pressure fluctuations on the blade surface confirm that the interaction between the OTSL and the blade row influences the liner’s dissipative characteristics and the blade row’s scattering behavior. Further investigations indicate that this interaction is correlated with the sound wave propagation direction, frequency, blade angle, and the sound absorption performance of the liner itself.

为了研究叶顶衬板对入射声波的降噪特性，本研究采用实验和数值相结合的方法，探讨了在无流动条件下，入射声波、过静叶衬板（OTSL）和叶片排之间的声学相互作用机制。实验对比结果表明，叶片排对衬垫的降噪效果有显著影响，对透射声和散射声都有较好的吸声效果。总体而言，OTSL的降噪效果优于仅使用衬垫。通过对声粒子速度和叶片表面压力波动的数值分析，证实了OTSL与叶片排的相互作用影响了衬里的耗散特性和叶片排的散射行为。进一步的研究表明，这种相互作用与声波的传播方向、频率、叶片角度和衬垫本身的吸声性能有关。

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引用次数: 0

Multi-band controllable acoustic topological insulator based on stacked composite resonant cavities 基于堆叠复合谐振腔的多波段可控声学拓扑绝缘体

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-12 DOI: 10.1016/j.apacoust.2026.111233

Xiao Liang , Zijing Yang , Jiangxia Luo , Nansha Gao , Guojian Zhou

The development of multi-band, wide-frequency, spectrum-tunable topological acoustic transmission is essential for the practical application of topological acoustic insulators. However, conventional approaches rely on complex structural reconfiguration or parameter modulation, which severely limits their flexibility. This paper addresses this issue by proposing a universal method of optimising multi-band structures based on stacked composite resonators. The key advantage of this strategy is that it provides comprehensive and flexible control over the number, width and position of operational frequency bands, simply by stacking and arranging resonators vertically. This approach neither alters the original scatterer geometry nor introduces additional parameters. Furthermore, it simplifies multiband control, allowing the operating bandwidth and position to be adjusted by merely altering the number and order of resonator layers. Research indicates that this method enables the on-demand introduction of multiple Dirac cones, as well as the flexible adjustment of existing frequency band widths and Dirac cone spectral positions. Each cone can open a bandgap independently and generate topologically protected one-way edge states. Superlattice simulations, acoustic field simulations and experimental measurements collectively confirm that all frequency bands exhibit the low transmission loss and strong defect immunity characteristic of topologically protected edge states. The proposed layered paradigm in this work revolutionises conventional band control approaches, offering a new way to develop high-performance, customisable, multiband acoustic topological devices.

发展多频带、宽频、频谱可调的拓扑声传输是拓扑绝缘体实际应用的必要条件。然而，传统的方法依赖于复杂的结构重构或参数调制，这严重限制了它们的灵活性。本文提出了一种基于堆叠复合谐振器的多波段结构优化的通用方法来解决这一问题。该策略的主要优点是，它提供了对工作频带的数量，宽度和位置的全面和灵活的控制，只需通过垂直堆叠和排列谐振器。这种方法既不会改变原有的散射体几何形状，也不会引入额外的参数。此外，它简化了多波段控制，允许通过仅仅改变谐振器层的数量和顺序来调整工作带宽和位置。研究表明，该方法可以按需引入多个狄拉克锥，并可灵活调整现有频带宽度和狄拉克锥谱位置。每个锥都可以独立地打开一个带隙，并产生拓扑保护的单向边缘状态。超晶格模拟、声场模拟和实验测量共同证实，所有频段都表现出拓扑保护边缘状态的低传输损耗和强缺陷抗扰特性。在这项工作中提出的分层范式彻底改变了传统的频带控制方法，为开发高性能、可定制的多频带声学拓扑器件提供了一种新方法。

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引用次数: 0

A simplified active noise control system with remote microphone technique based on blind source separation 一种基于盲源分离的简化的远程传声器主动噪声控制系统

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-10 DOI: 10.1016/j.apacoust.2026.111221

Tian Zhang, Ning Han, Zhehua Duan

Remote microphone technique is designed to solve the problem of physical microphones being inconvenient to install in a zone of quiet requiring noise attenuation. However, a typical remote microphone technique based system necessitates a sufficient number of monitoring microphones, generally no fewer than the number of noise sources, to ensure optimal noise reduction performance. Such requirements may lead to increased equipment costs and significant computational demands. In this paper, we develop a methodological approach to simplify the system based on blind source separation and remote microphone technique, aiming to reduce the number of microphones within the system. The main approach operates in three steps. First, the correlation of the sound field is analyzed to determine the microphone configuration. Second, the observation filter is modeled with monitoring microphone signals de-correlated by the blind source separation method. Third, the virtual signal estimated using the observation filter is employed in the active noise control system. Experimental results verify the superiority of the proposed algorithm in computational complexity. Furthermore, results also show that under various noise conditions, the proposed algorithm can achieve similar noise reduction performance as traditional systems while reducing the number of microphones required.

远程麦克风技术是为了解决物理麦克风不方便安装在需要消噪的安静区域的问题而设计的。然而，一个典型的基于远程麦克风技术的系统需要足够数量的监控麦克风，通常不少于噪声源的数量，以确保最佳的降噪性能。这样的要求可能会导致设备成本的增加和大量的计算需求。本文提出了一种基于盲源分离和远程传声器技术的系统简化方法，旨在减少系统内传声器的数量。主要的方法分为三个步骤。首先，分析声场的相关性，确定传声器的配置。其次，采用盲源分离法对监测麦克风信号进行去相关处理，建立观测滤波器模型；第三，将观测滤波器估计出的虚信号应用于有源噪声控制系统。实验结果验证了该算法在计算复杂度上的优越性。此外，研究结果还表明，在各种噪声条件下，该算法在减少所需麦克风数量的同时，可以达到与传统系统相似的降噪性能。

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引用次数: 0

Influence of transducer locations on acoustic impedance prediction in porous systems with application to vegetated roofs 传感器位置对多孔系统声阻抗预测的影响及其在植被屋顶上的应用

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-10 DOI: 10.1016/j.apacoust.2025.111213

Chang Liu , Fotis Georgiou , Maarten Hornikx

Urban vegetation, such as vegetated roofs, is effective in mitigating urban noise. In previous research, the acoustic impedance of vegetated roofs could be predicted by minimising the differences between the measured and pre-calculated level differences between two vertically placed microphones using the multiple-geometry technique. However, it was found that for some cases, the predicted sound pressure level differences deviated from the measured ones at the interference peaks. The sound pressure level produced by a single sound source above a ground surface is characterized by the interference of the direct and ground reflected sound waves, and the accuracy of the assumed locations of the transducers influences the prediction of the ground surface impedance. Therefore, the sensitivity of the transducers’ locations on the determination of the acoustic impedance of porous materials using the multiple-geometry technique was assessed in this research. It was found that small errors on the transducers’ locations lead to significant variations in predicted impedance and material properties. The tolerance of the extracted transducers’ locations is recommended to be within ± 0.005 m to achieve an accurate and unique prediction of the surface impedance of porous materials.

城市植被，如植被覆盖的屋顶，可以有效地减轻城市噪音。在之前的研究中，利用多重几何技术，可以通过最小化两个垂直放置的麦克风之间的测量和预先计算的电平差之间的差异来预测植被屋顶的声阻抗。然而，在某些情况下，在干扰峰处，预测的声压级差与实测的声压级差存在偏差。地面上单个声源产生的声压级具有直接声波和地面反射声波干扰的特征，换能器假设位置的准确性影响着地面阻抗的预测。因此，本研究评估了利用多几何技术测定多孔材料声阻抗时换能器位置的灵敏度。研究发现，传感器位置上的小误差会导致预测阻抗和材料性能的显著变化。提取的换能器位置的公差建议在±0.005 m以内，以实现对多孔材料表面阻抗的准确和独特的预测。

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引用次数: 0

Amplitude modulation of scattered acoustic waves by ULF oscillatory flow produced by submerged bodies: An experimental study 水下超低频振荡流对散射声波调幅的实验研究

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-09 DOI: 10.1016/j.apacoust.2026.111223

Ruixin Nie , Kaiqi Zhao , Bin Wang , Jun Fan , Yehao Shi

Sound waves propagating through media with local fluctuations experience phase and amplitude perturbations that carry valuable information about the medium. This principle offers potential for indirectly detecting moving submerged objects, as flow-induced acoustic modulations can reveal their motion characteristics. This study experimentally investigates the Amplitude Modulation (AM) of acoustic waves induced by Ultra-Low-Frequency (ULF) oscillatory flows generated by moving submerged bodies. Controlled tank experiments were conducted to examine the influence of oscillation amplitude, frequency, and movement pattern on single-frequency acoustic signals. Experimental results confirmed the occurrence of AM, with the acoustic signal acting as the carrier and the oscillatory flow as the modulation signal. It was observed that the modulation depth systematically increases with higher oscillation amplitudes and frequencies, demonstrating the pronounced influence of oscillatory flows on acoustic wave propagation. To gain deeper insights into the modulation mechanism, a theoretical framework based on the adiabatic normal mode approximation and perturbation methods was developed to interpret the observed phenomena, treating flow-induced sound speed variations as the primary mechanism for the observed modulation. The agreement between theoretical predictions and experimental observations supports the model’s ability to predict modulation characteristics based on hydrodynamic parameters. This study suggests the potential of using flow-induced acoustic modulations from moving objects as an indirect detection method, providing a foundation for future applications in underwater target detection and tracking.

声波在有局部波动的介质中传播时，会经历相位和振幅的扰动，这些扰动携带着有关介质的宝贵信息。这一原理为间接探测移动的水下物体提供了可能，因为流诱导的声学调制可以揭示它们的运动特性。本文通过实验研究了水下运动体产生的超低频振荡流对声波的调幅效应。通过控制槽实验，研究了振荡幅度、频率和运动方式对单频声信号的影响。实验结果证实了调幅的存在，以声信号作为载体，振荡流作为调制信号。观察到，随着振荡幅度和频率的增加，调制深度有系统地增加，表明振荡流对声波传播的显著影响。为了更深入地了解调制机制，建立了一个基于绝热法模近似和微扰方法的理论框架来解释观察到的现象，将流动引起的声速变化视为观察到的调制的主要机制。理论预测和实验观测之间的一致性支持了该模型预测基于水动力参数的调制特性的能力。本研究提出了利用运动物体的流诱导声调制作为一种间接检测方法的潜力，为未来在水下目标检测和跟踪中的应用奠定了基础。

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引用次数: 0

Unsupervised seabed habitat change detection with multibeam backscatter data using a constrained Gaussian mixture model 基于约束高斯混合模型的多波束后向散射数据无监督海底生境变化检测

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2026-01-07 DOI: 10.1016/j.apacoust.2026.111222

Qian Bai , Alireza Amiri-Simkooei , Sebastiaan Mestdagh , Dick G. Simons , Mirjam Snellen

Seabed backscatter data acquired by the multibeam echosounder (MBES) have been identified as a valuable indicator of sediment properties and benthic community characteristics. However, developing robust change detection models with MBES backscatter remains challenging due to the high costs and limited spatial coverage of seabed ground truth data. Lack of absolute backscatter calibration also hinders the comparison between repeated MBES measurements. To mitigate these issues, we propose an unsupervised method to detect seabed changes by fitting a Gaussian Mixture Model to the backscatter difference between two datasets. A relative calibration is conducted based on a stable reference area to eliminate the impact of possible drifts in echosounder characteristics on the backscatter difference. We then model the unchanged class as a zero-mean Gaussian distribution, with its variance constrained by the backscatter uncertainty estimated from the reference area. By processing each incident angle individually, the angular range with the greatest ability for seabed change detection can also be investigated. We demonstrate the effectiveness of the proposed method through two case studies in the Dutch North Sea. The detected changes reveal seasonal and temporal variations in benthic communities, such as sand mason worms, and are consistent with the sediment movement in one of the study areas. This research highlights the value of MBES backscatter data for seabed change detection and provides a cost-effective solution for seabed habitat monitoring with acoustic measurements.

多波束回声测深仪（MBES）获得的海底后向散射数据已被确定为沉积物性质和底栖生物群落特征的有价值的指标。然而，由于海底地面真值数据的高成本和有限的空间覆盖范围，开发具有MBES后向散射的鲁棒变化检测模型仍然具有挑战性。缺乏绝对后向散射校准也阻碍了重复MBES测量之间的比较。为了缓解这些问题，我们提出了一种无监督的方法，通过将高斯混合模型拟合到两个数据集之间的后向散射差来检测海底变化。基于稳定参考区域进行相对标定，消除测深特性可能漂移对后向散射差的影响。然后，我们将未改变的类别建模为零均值高斯分布，其方差受参考区域估计的后向散射不确定性的约束。通过对每个入射角进行单独处理，可以得到对海底变化检测能力最强的角度范围。我们通过荷兰北海的两个案例研究证明了所提出方法的有效性。探测到的变化揭示了底栖生物群落（如沙泥虫）的季节和时间变化，并与其中一个研究区域的沉积物运动相一致。本研究突出了MBES后向散射数据在海底变化检测中的价值，为海底栖息地声学监测提供了一种经济有效的解决方案。

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引用次数: 0