Applied Acoustics最新文献_第6页

Physical model experimental study on the infrasound characteristics of bedding slide in rock slope 岩坡垫层滑动次声特性的物理模型试验研究

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-30 DOI: 10.1016/j.apacoust.2024.110364

Qiao Chen , Dongming Jia , Yaobai Sun , Qingming Xie , Fenglin Xu , Rufu Zhou , Wei Peng , Jilong Chen , Jianrong Ma , Kang Yang

The main focus and challenge of landslide research is always the formation mechanism of bedding rock landslide. Preventing and controlling large-scale landslide is difficult due to high monitoring costs and short warning times, posing a significant challenge for accurate forecasting. In recent years, infrasound monitoring has been widely applied in the field of geological hazards. However, the infrasound characteristics of rock landslide remain unclear, hindering the application and promotion of this technology. Therefore, this study aimed to analyze the infrasound characteristics of bedding rock landslide through a physical model test. Through wavelet decomposition analysis of the experimental infrasound data, the study summarized the infrasound characteristics and energy distribution of rock landslide failure at various stages, as well as analyzed the correlation between the slide process and infrasound signals. The results showed that: (1) Infrasound signals are present in uniform deformation, accelerated deformation, slow sliding and rapid sliding stages of the bedding rock landslide, but the energy distribution is different for each stage, with the most apparent infrasound events occurring during accelerated deformation and rapid sliding stages. (2) During the deformation stage of the rock landslide, the infrasound waveform exhibits sharper features than during the sliding stage, with waveforms during the uniform deformation and slow sliding stages sloping to the right, and waveforms during the accelerated deformation and rapid sliding stages sloping to the left. (3) The infrasound frequencies in each stage are distributed between 0.01 and 20.0 Hz, among which the dominant frequencies in the uniform deformation stage and the slow sliding stage are mainly distributed between 0.01 and 10.0 Hz, and the dominant frequencies in the accelerated deformation stage and the rapid sliding stage are mainly distributed between 10.0 and 20.0 Hz. The findings of this study offer valuable insights for the development and application of rock landslide infrasound monitoring and early warning technology.

滑坡研究的重点和难点始终是垫层岩滑坡的形成机理。由于监测成本高、预警时间短，大规模滑坡的防治难度很大，给准确预报带来了巨大挑战。近年来，次声监测在地质灾害领域得到了广泛应用。然而，岩石滑坡的次声特征仍不明确，阻碍了该技术的应用和推广。因此，本研究旨在通过物理模型试验分析垫层岩石滑坡的次声特征。研究通过对试验次声数据进行小波分解分析，总结了岩石滑坡崩塌各阶段的次声特征和能量分布，并分析了滑动过程与次声信号之间的相关性。结果表明(1) 在垫层岩石滑坡的均匀变形阶段、加速变形阶段、缓慢滑动阶段和快速滑动阶段都存在次声信号，但各阶段的能量分布不同，其中加速变形阶段和快速滑动阶段的次声事件最为明显。(2）在岩石滑坡的变形阶段，次声波的波形特征比滑动阶段更明显，均匀变形和缓慢滑动阶段的波形向右倾斜，而加速变形和快速滑动阶段的波形向左倾斜。(3) 各阶段的次声频率分布在 0.01 至 20.0 Hz 之间，其中均匀变形阶段和慢速滑动阶段的主频率主要分布在 0.01 至 10.0 Hz 之间，加速变形阶段和快速滑动阶段的主频率主要分布在 10.0 至 20.0 Hz 之间。该研究结果为岩石滑坡次声监测和预警技术的开发与应用提供了宝贵的启示。

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引用次数: 0

Non-line-of-sight sound source localization based on block sparse Bayesian learning and second-order edge diffraction 基于块稀疏贝叶斯学习和二阶边缘衍射的非视距声源定位

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-30 DOI: 10.1016/j.apacoust.2024.110369

Qingbo Zhai , Fangli Ning , Juan Wei , Zhaojing Su

For environments where the sound source is located directly behind an obstacle, this work proposes a non-line-of-sight sound source localization algorithm based on fast marginalized block sparse Bayesian learning (BSBL-FM) and second-order edge diffraction. The second-order edge diffraction transfer function is calculated using the Biot-Tolstoy-Medwin method and used to construct the sensing matrix. By leveraging the spatial sparsity of the sound source signal, a block sparse measurement model is formulated, and BSBL-FM is applied for sparse reconstruction to achieve high-resolution localization. Simulation results demonstrate that the proposed algorithm accurately locates the source position and identifies the source strength, providing higher spatial resolution than beamforming and more precise source strength identification than matched-field processing (MFP). Experimental results validate the simulation findings and further show that the proposed algorithm achieves smaller localization errors than both beamforming and MFP.

针对声源位于障碍物正后方的环境，本研究提出了一种基于快速边际块稀疏贝叶斯学习（BSBL-FM）和二阶边缘衍射的非视距声源定位算法。使用 Biot-Tolstoy-Medwin 方法计算二阶边缘衍射传递函数，并利用该函数构建传感矩阵。利用声源信号的空间稀疏性，制定了块稀疏测量模型，并应用 BSBL-FM 进行稀疏重建，从而实现高分辨率定位。仿真结果表明，所提出的算法能准确定位声源位置并识别声源强度，比波束成形算法提供更高的空间分辨率，比匹配场处理算法（MFP）提供更精确的声源强度识别。实验结果验证了仿真结果，并进一步表明，与波束成形和匹配场处理相比，所提算法的定位误差更小。

引用次数: 0

On the accuracy of finite-difference time-domain simulations of head-related transfer functions as a function of model complexity 头部相关传递函数的有限差分时域模拟精度与模型复杂度的关系

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-30 DOI: 10.1016/j.apacoust.2024.110353

Julie Meyer , Sebastian Prepeliţă , Lorenzo Picinali

Wave-based numerical tools such as finite-difference time-domain (FDTD) solvers are useful for modeling several acoustic properties and interactions. While these numerical tools are widely used in acoustics, there seems to be less attention to assessing the quality of the produced outputs. However, in order to ensure that the obtained results are reliable, the quantification of the errors present in the simulation results is an essential step. There exists a mathematical process known as solution verification which aims at assessing the accuracy of the computed solutions. A relevant application for the FDTD method is the simulation of head-related transfer functions (HRTFs), since these are relatively complex to acoustically measure on humans. This paper aims at applying the solution verification process on HRTF modeling using the FDTD method to evaluate the accuracy of the simulated HRTF magnitudes with increased human head/torso model complexity. The FDTD-simulated HRTFs are also compared with respect to the similarity/dissimilarity of their spectrum and with respect to the relevance of these spectral variations on sound source localization. The results show that asymptotically extrapolating the FDTD-simulated HRTFs from a series of simulations provides more accurate HRTF predictions when compared to using single FDTD simulations ran on sub-millimeter grids, regardless of the model complexity. Results also demonstrate that the accuracy of the FDTD-simulated HRTF predictions decreases with increased model complexity. The localization performance predictions showed that the largest localization errors were obtained with models with the lowest complexities. Significant differences in predicted sound source localization performance were found between FDTD-simulated results.

基于波的数值工具，如有限差分时域（FDTD）求解器，可用于对多种声学特性和相互作用进行建模。虽然这些数值工具被广泛应用于声学领域，但人们似乎不太关注对所生成结果的质量进行评估。然而，为了确保获得的结果是可靠的，量化模拟结果中存在的误差是必不可少的一步。有一种称为 "解决方案验证 "的数学过程，旨在评估计算解决方案的准确性。FDTD 方法的一个相关应用是模拟与头部相关的传递函数 (HRTF)，因为对人体进行声学测量相对复杂。本文旨在利用 FDTD 方法对 HRTF 建模进行求解验证，以评估随着人体头部/躯干模型复杂度的增加，模拟 HRTF 幅值的准确性。本文还比较了 FDTD 模拟 HRTF 的频谱相似性/相似性，以及这些频谱变化与声源定位的相关性。结果表明，与使用亚毫米网格上运行的单个 FDTD 仿真相比，无论模型的复杂程度如何，从一系列仿真中渐近外推 FDTD 仿真的 HRTF 都能提供更准确的 HRTF 预测。结果还表明，FDTD 模拟 HRTF 预测的准确度会随着模型复杂度的增加而降低。定位性能预测显示，复杂度最低的模型获得的定位误差最大。FDTD 模拟结果与声源定位性能预测结果之间存在显著差异。

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引用次数: 0

Ultrasonic dry-coupling detection with gradient acoustic impedance match layer 带梯度声阻抗匹配层的超声干耦合检测

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-28 DOI: 10.1016/j.apacoust.2024.110355

Donglin Tang , Sheng Rao , Chao Ding , Chao Qin

Ultrasonic dry coupling technology eliminates the need for traditional liquid coupling agents and is critical for detecting advanced materials or coatings that cannot be contaminated by liquid coupling agents. In the conventional dry-coupling technique, sound waves propagate within a multilayer medium of water, dry-coupling material (rubber), and the material being examined (steel). The serious impedance mismatch between multilayer media results in very low ultrasonic transmission efficiency, and the maximum transmission coefficient of sound intensity is only 0.12. To improve the acoustic transmission performance, this paper proposes a dry coupling layer with gradient variation of acoustic impedance, whose impedance varies with an exponential law in the thickness direction. In the first stage, the propagation laws of acoustic waves in multilayer media with varying acoustic impedance gradients were investigated. Boundary impedance mismatch conditions were introduced, and the effects of different acoustic impedance mismatches on the acoustic properties of dry coupling layers were investigated based on acoustic transmission theory analysis. In the second stage, based on the optimized parameters after numerical analysis, the gradient composites were fabricated by centrifugal method, and dry-coupling detection experiments were carried out. Experimental results confirmed that the dry coupling layer with an exponential change in acoustic impedance improved the sound propagation efficiency by 80 % and the −6dB bandwidth of the pulse-echo signal by 20 % compared to rubber.

超声干耦合技术无需使用传统的液体耦合剂，对于检测液体耦合剂无法污染的先进材料或涂层至关重要。在传统的干耦合技术中，声波在由水、干耦合材料（橡胶）和被检材料（钢）组成的多层介质中传播。多层介质之间严重的阻抗失配导致超声波传输效率非常低，声强的最大传输系数仅为 0.12。为了改善声波传输性能，本文提出了一种声阻抗梯度变化的干耦合层，其阻抗在厚度方向上呈指数规律变化。在第一阶段，研究了声波在声阻抗梯度变化的多层介质中的传播规律。引入了边界阻抗失配条件，并基于声学传输理论分析研究了不同声阻抗失配对干耦合层声学特性的影响。第二阶段，根据数值分析后的优化参数，采用离心法制作了梯度复合材料，并进行了干耦合检测实验。实验结果证实，与橡胶相比，声阻抗呈指数变化的干耦合层提高了 80% 的声传播效率，脉冲回波信号的 -6dB 带宽提高了 20%。

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引用次数: 0

Unsupervised selection of acoustic indices: An experimental comparison for characterizing unlabeled audio recordings from sub-Andean forest soundscapes 声学指数的无监督选择：对安第斯山下森林声景中的无标记录音进行特征描述的实验比较

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-24 DOI: 10.1016/j.apacoust.2024.110363

Ana Lorena Uribe-Hurtado , Fernando Martínez-Tabares , Mauricio Orozco-Alzate

We present an experimental comparison of applying six unsupervised (i.e. not relying on class labels) and almost parameterless feature selection methods for ranking acoustic indices. The study is aimed at guiding the practitioner in choosing appropriate acoustic indices when, in absence of class labels, a small but meaningful number of features to characterize soundscapes is desired. Forty acoustic indices were considered, which correspond to seventeen temporal, spectral and soundscape features, along with their basic statistics. Three publicly available soundscape datasets, registered in a sub-Andean forest, were used for the experiments; moreover, several subsets were considered according to the different times of the day. Results reveal that the Acoustic Evenness Index is the most important one in terms of representational power according to the six considered selection criteria, followed by the Acoustic Complexity Index when conditions are relaxed to examine features ranked among the top-five. Besides, the Bioacoustic Index, the Acoustic Diversity Index and the Root Mean Square Energy stand out as important features when characterizing days in their separated parts.

我们在实验中比较了六种无监督（即不依赖类标签）和几乎无参数的特征选择方法，用于声学指数排序。这项研究旨在指导从业人员在没有类别标签的情况下，选择适当的声学指数，以少量但有意义的特征来描述声景。我们考虑了 40 种声学指数，它们与 17 种时间、频谱和声景特征及其基本统计数据相对应。实验使用了三个公开的声景数据集，这些数据集在一个亚安第斯森林中登记；此外，还根据一天中的不同时间考虑了几个子集。结果表明，根据所考虑的六项选择标准，就代表性而言，声学均匀度指数是最重要的指数，其次是声学复杂性指数，如果放宽条件来考察排在前五位的特征的话。此外，生物声学指数、声学多样性指数和均方根能量也是表征分隔部分日的重要特征。

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引用次数: 0

Ultra-thin low-frequency broadband absorber based on layered coiled channel structure 基于分层盘绕通道结构的超薄低频宽带吸收器

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-23 DOI: 10.1016/j.apacoust.2024.110358

Wenli Sun , Yonghua Wang , Haidong Yuan , Wenbo Guo , Yan Wang , Jingze Xue , Huadong Yu

To improve and broaden the performance in absorbing sound waves of metamaterials at the lower and mid-frequency ranges, a layered coiled channel composite structure (LCCS) with deep subwavelengths is proposed in this paper, which extends the acoustic wave propagation paths longitudinally by connecting the Helmholtz resonator channels in each layer and achieves the multistep resonance of the coupling cavities, which results in the cancellation of acoustic energies, reduces the acoustic reflections and scattering, and enhances the absorption performance. A model to simulate theoretical sound absorption and finite elements simulation of the metamaterial were evolved to reveal its potential mechanism for absorbing sound. Using the single-variable method to study the impact of altering structural parameters on the effectiveness of sound absorption, it shows good tunability in the target frequency range and obtains four fundamental unit LCCSs having distinct frequency absorption peaks, and designs a multi-unit coupling construction having low frequencies wideband sound absorption performance by connecting them in parallel to realize a large-broadband continuous and high-efficiency sound absorption within the scope of 370–1400 Hz, using a mean peak sound absorption value higher than 0.7. The structure was put together by 3D printing, and the impedance tube method test verified the precision of the simulation’s findings. This study offers a practical means to create lightweight, low-frequency broadband acoustic absorbing metamaterials.

为了改善和拓宽超材料在中低频段的吸声性能，本文提出了一种具有深亚波长的分层盘曲通道复合结构（LCCS），通过连接各层的亥姆霍兹谐振器通道，纵向扩展声波传播路径，实现耦合腔的多级共振，从而抵消声能，减少声反射和散射，提高吸声性能。为了揭示超材料潜在的吸声机理，我们建立了理论吸声模拟模型，并对超材料进行了有限元模拟。利用单变量法研究了改变结构参数对吸声效果的影响，在目标频率范围内显示出良好的可调性，获得了四个具有不同频率吸声峰值的基本单元 LCCS，并通过并联设计出具有低频宽带吸声性能的多单元耦合结构，实现了 370-1400 Hz 范围内的大宽带连续高效吸声，平均吸声峰值大于 0.7。该结构由三维打印组装而成，阻抗管法测试验证了模拟结果的精确性。这项研究为制造轻质、低频宽带吸声超材料提供了一种实用方法。

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引用次数: 0

Characterization of noise sources in two- and three-element high-lift airfoil configurations 二元和三元高升力机翼配置中噪声源的特征描述

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-23 DOI: 10.1016/j.apacoust.2024.110354

Marinus K. Okoronkwo , Dominic G. Geneau , Jessica M. Eburn , Hadar Ben-Gida , Oksana Stalnov , Stéphane Moreau , Philippe Lavoie

To improve the current understanding of flap noise generation mechanisms in high-lift devices used by small- to large-size commercial aircraft, a detailed study of both two- and three-element configurations of the canonical high-lift 30P30N airfoil has been conducted. Results from unsteady Reynolds-Averaged Navier-Stokes simulations are compared with aerodynamic and acoustic measurements in the hybrid anechoic wind tunnel at the University of Toronto to gain better physical insights into the flow phenomena associated with the noise sources in multi-element configurations. It is shown that the slat element has little impact on the flow in and around the flap and flap gap when the main wing is at the same orientation relative to the incoming flow. Tonal peaks are found both in the flap cove and on the flap, matching the tonal noise produced by the slat when in the three-element configuration. These peaks are present at the flap due to pressure waves that emanate from the slat and propagate downstream. Analysis of the frequency wavenumber spectra of the unsteady pressure along the main element pressure surface shows the existence of forward- and backward-traveling acoustic waves, providing evidence of a feedback loop between the two coves, which amplifies the narrowband tonal peaks in both coves. These tones disappear from the flap when the slat is removed in a two-element configuration, with the flap-cove overall broadband pressure fluctuation levels remaining unchanged.

为了提高目前对小型到大型商用飞机所使用的高升力装置中襟翼噪声产生机制的理解，对典型高升力 30P30N 机翼的两元素和三元素配置进行了详细研究。将非稳态雷诺平均纳维-斯托克斯模拟结果与多伦多大学混合消声风洞中的气动和声学测量结果进行了比较，以便更好地了解多元素配置中与噪声源相关的流动现象。结果表明，当主翼相对于流入气流的方向相同时，板条元件对襟翼和襟翼间隙内部和周围的气流影响很小。在襟翼凹槽和襟翼上都发现了音调峰值，与三元件配置时板条产生的音调噪声相匹配。这些峰值出现在襟翼处的原因是板条产生的压力波向下游传播。对沿主元件压力面的不稳定压力的频率波谱分析表明，存在向前和向后传播的声波，这证明两个凹槽之间存在反馈回路，从而放大了两个凹槽中的窄带音调峰值。在双元件配置中移除板条时，这些音调会从襟翼中消失，而襟翼-凹槽整体宽带压力波动水平保持不变。

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引用次数: 0

A fault diagnosis method for bogie axle box bearing based on sound-vibration multiple signal fusion 基于声振多信号融合的转向架轴箱轴承故障诊断方法

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-21 DOI: 10.1016/j.apacoust.2024.110336

Zejun Zheng, Dongli Song, Weihua Zhang, Chen Jia

The fault diagnosis method of multi-signal fusion is one of the current research trends, which can improve the reliability of diagnosis results. In this paper, the single channel signal is decomposed by multi-channel bandpass filter bank, and a new indicator value is constructed to select the optimal component. A new fusion demodulation method is constructed by using the two signal demodulation methods to extract the characteristic frequency of the single channel signal. Subsequently, the characteristic spectrum of the multi-channel signals is fused to extract the final characteristic frequency. The diagnosis method is verified by the simulation signal and the sound signal and vibration signal collected by the experiment. The results show that the proposed method can reduce the content of noise components in the characteristic spectrum, highlight the fault characteristic frequency, and reflect the superiority of the proposed method compared with other methods. This paper provides guidance for feature extraction of data fusion methods in the future, and provides an effective method for fault diagnosis and condition monitoring of bearings.

多信号融合的故障诊断方法是当前的研究趋势之一，它可以提高诊断结果的可靠性。本文通过多通道带通滤波器组对单通道信号进行分解，并构建新的指标值来选择最优分量。利用两种信号解调方法构建了一种新的融合解调方法，以提取单通道信号的特征频率。随后，融合多通道信号的特征频谱，提取最终的特征频率。诊断方法通过仿真信号和实验采集的声音信号和振动信号进行了验证。结果表明，所提出的方法可以减少特征频谱中噪声成分的含量，突出故障特征频率，体现了与其他方法相比的优越性。本文为今后数据融合方法的特征提取提供了指导，为轴承的故障诊断和状态监测提供了一种有效的方法。

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引用次数: 0

Locating and reconstructing transformer low-frequency noises with a 3D, six-microphone array 利用三维六麦克风阵列定位和重建变压器低频噪声

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-21 DOI: 10.1016/j.apacoust.2024.110351

Yazhong Lu , Sean F. Wu , Chuanbin Nie , Wen He

This paper presents diagnosis and analyses of the sound fields radiated from power transformers in 3D space under normal operational conditions. Transformers are crucial components in the power system. Good condition of a transformer is an important factor to ensure safe and reliable operations of the entire power system. Diagnosis and analyses of transformer noise are challenging because of the complexity of the acoustic environment surrounding the power grid. Previous studies have revealed that transformer noise is predominantly concentrated in the low frequency range. This low-frequency nature of transformer noise has made it extremely difficult to pinpoint the precise source locations. The present study shows that by using the Sound Viewer system, which is built on the principles of passive SODAR (Sonic Detection And Ranging) and HELS (Helmholtz Equation Least Squares) methods, we can not only pinpoint the precise locations of noise sources of a transformer, but quantify individual source strengths. Specifically, SODAR enables one to locate multiple sound sources simultaneously in 3D space over the frequency range of 20–20,000 Hz, and the HELS method enables one to reconstruct the acoustic field and acquire the optimal approximation of the acoustic pressure distribution in 3D space, time-averaged acoustic intensities, and time-averaged acoustic powers of the individual acoustic sources. The accuracy in reconstruction depends on the SNR (Signal to Noise Ratio) of the input data. The higher the SNR is, the more accurate the reconstruction becomes. Moreover, by using a spatial filter, we can eliminate the interferences of unwanted sound sources and extract the time-averaged acoustic power of a specific target. This salient feature enables us to perform a source ranking, which can be critical in designing the most cost-effective noise mitigation strategy. Results of the present study demonstrate that this technology can play a significant role in diagnosing and analyzing complex acoustic field in a non-ideal test environment, especially for transformer health monitoring and predictive maintenance in power systems.

本文对电力变压器在正常运行条件下的三维空间声场辐射进行了诊断和分析。变压器是电力系统中的关键部件。变压器的良好状态是确保整个电力系统安全可靠运行的重要因素。由于电网周围声学环境的复杂性，变压器噪声的诊断和分析具有挑战性。以往的研究表明，变压器噪声主要集中在低频范围。变压器噪声的这种低频特性使得精确定位噪声源极为困难。本研究表明，通过使用基于被动 SODAR（声波探测与测距）和 HELS（亥姆霍兹方程最小二乘法）原理的声音查看器系统，我们不仅可以精确定位变压器噪声源的位置，还可以量化单个噪声源的强度。具体来说，SODAR 可以在 20-20,000 Hz 的频率范围内同时定位三维空间中的多个声源，而 HELS 方法则可以重建声场，并获得三维空间中声压分布、时间平均声强和单个声源的时间平均声功率的最佳近似值。重建的精度取决于输入数据的信噪比（SNR）。信噪比越高，重建就越精确。此外，通过使用空间滤波器，我们可以消除无用声源的干扰，提取特定目标的时间平均声功率。这一显著特征使我们能够进行声源排序，这对于设计最具成本效益的噪声缓解策略至关重要。本研究的结果表明，这项技术可以在诊断和分析非理想测试环境中的复杂声场方面发挥重要作用，特别是在电力系统的变压器健康监测和预测性维护方面。

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引用次数: 0

Smooth topological design of lightweight vibro-acoustic sandwich structures by maximizing sound transmission loss 通过最大化传声损耗实现轻质振动声学夹层结构的平滑拓扑设计

IF 3.4 2区物理与天体物理 Q1 ACOUSTICS

Applied Acoustics

Pub Date : 2024-10-21 DOI: 10.1016/j.apacoust.2024.110347

Jiao Xu , Jie Hu , Jiachun Li , Yugang Li , Ning Gan , Meng Tao , Wenkang Cao

The vibro-acoustic coupling mechanism and its optimization design of lightweight sandwich structures are globally hot research topics. The traditional parameter adjustment approach highly relies on the experience of designers, which makes it difficult to achieve lightweight design while regulating the acoustic insulation performance of sandwich structures at a limited cost. This paper proposes a new dynamic three-field floating projection topology optimization (FPTO) method to conduct vibro-acoustic coupling topological design for lightweight insulated sandwich structures, to achieve superior sound insulation performance by maximizing sound transmission loss with a volume constraint. The effectiveness and accuracy of the proposed method were verified on representative 2D and 3D numerical examples and also validated with impedance tube tests. The results show that novel optimized structures with a smooth boundary for practical applications and superior acoustic insulation performance than conventional designs can be obtained based on the proposed method. For instance, at an optimization target frequency of 1200 Hz, the total sound transmission loss, corresponding to the optimized target sound insulation performance of the 3D sandwich case, showed an improvement from 56.68 dB to 70.8 dB, compared to the common closed honeycomb structures in engineering practice under the equal mass conditions. Moreover, the numerical simulation and experimental results showed good agreement. The study suggests that the dynamic three-field FPTO method is promising for optimizing acoustic and vibration performance in lightweight vibro-acoustic sandwich structures.

轻质夹层结构的振声耦合机理及其优化设计是全球研究的热点。传统的参数调整方法高度依赖设计人员的经验，难以在有限的成本下实现轻量化设计的同时调节夹层结构的隔声性能。本文提出了一种新的动态三场浮动投影拓扑优化（FPTO）方法，对轻质隔声夹层结构进行振声耦合拓扑设计，在体积约束下通过最大化传声损失实现优异的隔声性能。该方法的有效性和准确性在代表性的二维和三维数值示例中得到了验证，并通过阻抗管测试进行了验证。结果表明，基于所提出的方法，可以获得适用于实际应用的具有平滑边界的新型优化结构，其隔音性能优于传统设计。例如，在 1200 Hz 的优化目标频率下，与等质量条件下工程实践中常见的封闭式蜂窝结构相比，三维夹层结构的总传声损耗（与优化目标隔声性能相对应）从 56.68 dB 提高到 70.8 dB。此外，数值模拟和实验结果显示出良好的一致性。研究表明，动态三场 FPTO 方法有望优化轻质振动声学夹层结构的声学和振动性能。

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引用次数: 0