Applied Acoustics最新文献

{"title":"Numerical investigation of the impeller blockage effect on centrifugal fan noise using a hybrid prediction approach with rotating system","authors":"Ye Yuan ,&nbsp;Youhong Xiao ,&nbsp;Qiannan Xu ,&nbsp;Fujian Zhao","doi":"10.1016/j.apacoust.2025.111154","DOIUrl":"10.1016/j.apacoust.2025.111154","url":null,"abstract":"<div><div>In this study, a hybrid aeroacoustic prediction approach incorporating the effects of a rotating system is proposed to calculate the aerodynamic noise generated by centrifugal fan operation. Additionally, the blockage effect caused by the impeller on the propagation of broadband noise is investigated. The relative motion between the rotating impeller and the volute is modeled using a sliding grid technique. The Improved Delayed Detached-Eddy Simulation (IDDES) is employed to resolve the flow field and compute the acoustic source term, which is subsequently coupled with the Acoustic Perturbation Equations (APEs) to simulate the generation and propagation of the fan noise. The flow and acoustic fields are solved simultaneously on a single grid, eliminating the need to store large datasets and avoiding interpolation errors between grids. The accuracy of the approach is validated using benchmark acoustic problems. Comparison of the numerical results of the centrifugal fan with the experimental data shows that the deviation in Overall Sound Pressure Level (OASPL) at the four microphone locations ranges from 1.9 dB to 3.4 dB, demonstrating the validity of the approach in predicting aeroacoustic behavior in complex rotating systems. Furthermore, the blockage effect of the impeller on noise propagation is investigated in detail. For acoustic sources located in the volute tongue region, this effect not only influences the spatial distribution of acoustic energy but also causes a shift and redistribution of acoustic energy across different frequency bands.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111154"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145571861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distributed particle filtering based on stein variational gradient descent for acoustic source tracking","authors":"Yuan Jing ,&nbsp;Hao Song","doi":"10.1016/j.apacoust.2025.111168","DOIUrl":"10.1016/j.apacoust.2025.111168","url":null,"abstract":"<div><div>This paper proposes a novel distributed particle filtering algorithm for acoustic source tracking in distributed microphone networks within the Bayesian filtering framework. The core innovation leverages multiple tempering Stein variational gradient descent to efficiently fuse probability density functions of the local posteriors across the network, minimizing Kullback-Leibler divergence. At each sensor node, the probability density functions of local posteriors are first approximated using particles via sequential Monte Carlo sampling. To enable communication-efficient distributed consensus, these particles model local posteriors as Gaussian mixture distributions. Neighboring nodes exchange these local Gaussian mixture posteriors. Within each average consensus iteration, a multiple tempering Stein variational gradient descent sampler generates samples approximating the fused posterior, defined as the product of fractional powers of the received Gaussian mixture posteriors. This process yields a consistent approximation of the global posterior probability density on every node from the fused samples. The algorithm’s effectiveness is validated through both distributed acoustic source tracking simulations and a real-world recording experiment.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111168"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145571918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Zwicker and Moore–Glasberg loudness levels with common level-based measures in the assessment of environmental noises in daily life","authors":"Akiko Sugahara ,&nbsp;Miki Yonemura ,&nbsp;Shinichi Sakamoto","doi":"10.1016/j.apacoust.2025.111164","DOIUrl":"10.1016/j.apacoust.2025.111164","url":null,"abstract":"<div><div>A-weighting is commonly used in environmental noise regulations and standards across many countries due to its simplicity and practicality. However, it does not always align with subjective loudness perception, particularly for characteristic sounds. In contrast, the loudness levels defined in ISO 532–1 (Zwicker method) and ISO 532–2 (Moore–Glasberg method) more accurately reflect human auditory response. Despite this advantage, their practical application has been limited by computational complexity and limited field data. This study focuses on a systematic comparison of the two standardized loudness metrics (Zwicker and Moore–Glasberg) against one another and with A-weighted sound pressure levels, in the context of environmental noise evaluation. To support this comparison, an efficient and practical system for real-time loudness level measurement was developed and implemented on a tablet-based, multifunctional measuring device. The system enables simultaneous calculation and direct comparison of both ISO 532–1 and ISO 532–2 loudness levels during on-site environmental noise monitoring. First, the frequency and level dependencies of each method were analyzed through numerical experiments. Subsequently, field measurements were conducted to capture instantaneous loudness levels and energy-averaged equivalent loudness levels over the entire measurement period for various environmental noise sources. The results consistently demonstrated method-dependent differences in loudness indices across both numerical experiments and field measurements. Notably, characteristic phenomena such as reversals in loudness levels between methods were observed, depending on the frequency content, temporal variations, and level ranges of the noise sources. These findings provide novel insights into the behavior and interpretability of standardized loudness metrics under real-world acoustic conditions and may support their broader application in perceptually relevant environmental noise assessment.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111164"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145571917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultra-broadband dual-mode nonlocal sound absorber based on phase gradient Fabry-Perot slit channels","authors":"Jin He,&nbsp;Qingxuan Liang,&nbsp;Dichen Li","doi":"10.1016/j.apacoust.2025.111166","DOIUrl":"10.1016/j.apacoust.2025.111166","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111166"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145571916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of varying basalt fibre size on the acoustical properties of low carbon concrete","authors":"Haydar Aygün,&nbsp;Amer Ali,&nbsp;Ali Bayyati","doi":"10.1016/j.apacoust.2025.111167","DOIUrl":"10.1016/j.apacoust.2025.111167","url":null,"abstract":"<div><div>The impact of varying basalt fibre size and perforating concrete samples was investigated to improve the acoustical properties of low-carbon concrete. The research was focused on how the length and quantity of basalt fibres and perforation of samples could influence sound absorption and transmission, with an intention to apply them as sound reflectors and sound absorbers. Concrete samples both with and without perforations were designed and created. Their sound absorption coefficient and transmission loss values of the samples were measured applying transfer function method in a circular metal impedance tube. Two-Dimensional (2D) computational simulations were carried out on periodic perforated material that are mimicking perforated concrete samples to determine their sound transmission loss values and absorption coefficients applying the thermo-viscous acoustics, pressure acoustics, and solid mechanics models in COMSOL Multiphysics software. Computational results matched up well with the experimental results for perforated materials in one-third octave bands. The results reveal that varying basalt fibre size and quantity of them within materials significantly influences the sound absorption mechanism of the concrete causing the samples to behave like resonators around their natural frequency. Introducing perforations into samples enhanced sound absorption performance and moved the peak absorption to higher frequencies. However, the increase in sound absorption came with a trade-off, decreased sound transmission loss, meaning more sound passed through the perforated samples. Finally, the average sound absorption coefficients and transmission loss values of the basalt fibre reinforced samples were compared to those of glass-bead samples and to the concrete samples without basalt fibre infusion. The results clearly showed that adding basalt fibres to concrete boosted sound absorption coefficient and the frequency at which the peak sound absorption occurs was shifted to lower frequencies.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111167"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145571915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sound reductions of plenum windows installed with cylindrical scatterer arrays in the presence of a linear sound source","authors":"Wai Kit Lam ,&nbsp;S.K. Tang","doi":"10.1016/j.apacoust.2025.111172","DOIUrl":"10.1016/j.apacoust.2025.111172","url":null,"abstract":"<div><div>A scale model experiment was carried out in the present study to understand the sound transmission losses across acoustic plenum windows installed with the ‘sonic crystal like’ cylindrical scatterer arrays with square and rhombic lattices in the presence of an incoherent linear sound source. The effects of the band structures of these arrays, the plenum window dimensions and the sound source orientation angle on the sound transmission losses were also examined. The results illustrated that the traffic noise transmission loss increases with increasing filling fraction, but meaningful noise reduction enhancement is only possible at filling fractions greater than 0.033. A larger window gap width results in improved angular uniformity of noise reduction. Stronger sound transmission loss is achieved with those scatterer array configurations having a half scatterer attached to the window panes. The arrays with square lattice and half scatterers on the window panes gives the best sound reduction. It is also evident that the band structures of the arrays have no effect on the spectral characteristics of the sound transmission when the sound source is nearly parallel to the window. Strong influences of the standing waves formed within the window inlet cavity are observed under such circumstance. The bandgaps of the scatterer arrays in general run over regions of high spectral sound transmission loss or of strongly increasing sound transmission loss. However, the sound transmission losses vary within each bandgap. Besides, it is found that the density of the bandgaps does not have direct relationship with the magnitude of the sound transmission loss. The length-wise acoustic modes of the window cavity only have limited effect of the sound transmission loss even at frequencies below the lowest bandgap eigenfrequency.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111172"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145618553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analog emulator designs for the auditory neurons and their performance comparison with the dynamic time warping algorithm","authors":"Nimet Korkmaz,&nbsp;Mustafa Molu","doi":"10.1016/j.apacoust.2025.111173","DOIUrl":"10.1016/j.apacoust.2025.111173","url":null,"abstract":"<div><div>In auditory system, after the frequencies of sound signals are modulated by the basilar membrane, these sounds of different frequencies are processed by different auditory neurons. Design of the broadband electronic circuits is a critical issue to emulate the auditory neurons, because these emulator circuit processes the sound signal of various frequency without require any update. In this study, it is aimed to compare the response performance of the auditory neuron emulator circuits that are built by several analog devices. In this context, an auditory neuron model, which is defined by adapting the vibrations in a piezoelectric ceramic to the FitzHugh–Nagumo neuron model, is successfully implemented with voltage operational amplifier, operational transconductance amplifiers, current feedback operational amplifiers and field programmable analog arrays. After the notes of a musical composition are coded in a microcontroller, its electrical signal output is applied to the auditory neuron emulator circuits as an external excitation signal. The peaks of the excitation signal applying to the emulator circuits and the firing times of the dynamic responses measuring from the outputs of these analog circuits are recorded simultaneously. Then, time differences between stimulus peaks and neuronal firing responses are determined with the “Dynamic Time Warping” algorithm and the input/output synchronization performances of these analog emulators are compared according to the result of this quantitative measurement.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111173"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145618551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of common excess-phase zeros for single-input multiple-output room response equalization via ringing quantification","authors":"Dongcai Wang,&nbsp;Ziyun Liu,&nbsp;Yiming Han,&nbsp;Keyu Pan,&nbsp;Yong Shen","doi":"10.1016/j.apacoust.2025.111153","DOIUrl":"10.1016/j.apacoust.2025.111153","url":null,"abstract":"<div><div>Mixed-phase equalization filters are widely employed for enhancing multi-position audio quality in single-input multiple-output (SIMO) room response equalization systems. A spatially robust polynomial equalization method based on identification of common excess-phase zeros (CEZ) has been proposed to design mixed-phase filters that mitigate magnitude distortions and pre-ringing effects. However, existing CEZ identification methods are limited by clustering frameworks and fail to consider key factors such as filter design strategy, truncation length and mutual modulation effects, resulting in ineffective CEZ identification. To address this, a systematic three-stage CEZ identification method is proposed. First, excess-phase zeros are rapidly computed via sub-band decomposition. Next, relative CEZ clusters are extracted across frequency bands. Finally, CEZ are identified through sorting and screening of these candidates. The proposed method is evaluated using impulse responses from realistic environments to compare various CEZ identification approaches. Additionally, the effect of different parameter settings on equalization performance is examined. Objective and subjective evaluations indicate that filters designed with the CEZ identified by the proposed method achieve optimal filtering performance. The proposed method enhances the performance of SIMO mixed-phase filters, providing a systematic solution for achieving robust room response equalization in complex acoustic environments.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111153"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145571919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectral and tonality characterization of unwanted environmental sounds for automatic noise assessment","authors":"Luca Fredianelli ,&nbsp;Gino Iannace ,&nbsp;Andac Akbaba","doi":"10.1016/j.apacoust.2025.111171","DOIUrl":"10.1016/j.apacoust.2025.111171","url":null,"abstract":"<div><div>In environmental acoustics, especially during long-term outdoor measurements, unwanted sounds can compromise the reliability of noise assessments. Traditionally, their identification and removal require extensive manual work. Recent advances in machine learning for Sound Event Classification and Detection offer new perspectives for automating such tasks. This study, based on the publicly available DataSEC dataset, presents a spectral and tonal characterization of 40 classes of environmental sounds commonly encountered in urban and rural contexts. Third-octave spectra, spectrograms, and probabilistic tonality maps are analyzed to describe intra- and inter-class variability and to identify recurring spectral structures. The results provide a reference framework for understanding how different sources contribute to tonal and broadband features in environmental recordings. The analysis also discusses how these descriptors can support future automated workflows, including frequency-domain post-processing or spectral smoothing strategies, without claiming experimental validation of such methods. By offering comprehensive, normalized spectral and tonal features, this work provides an open reference for both acoustic professionals and researchers aiming to develop or train machine learning models for environmental sound assessment and event recognition.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111171"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145618552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acoustic reflection modeling and experimental study of rough fractal interfaces for dry-coupled ultrasonic testing","authors":"Yuanyao Hu ,&nbsp;Donglin Tang ,&nbsp;Sheng Rao ,&nbsp;Chao Ding ,&nbsp;Weiping Wu","doi":"10.1016/j.apacoust.2025.111174","DOIUrl":"10.1016/j.apacoust.2025.111174","url":null,"abstract":"<div><div>This study investigates the enhancement of acoustic performance in ultrasonic dry coupling for solid rough interfaces, focusing on the coupling characteristics of ultrasound propagation through rough contact interfaces. A dry coupling acoustic model is developed based on the Distributed Spring Model (DSM), and a contact stiffness expression incorporating the fractal dimension is derived. Numerical simulations are conducted to analyze the relationship between interface coupling stiffness and load, and a piecewise mapping method is proposed to provide a quantitative basis for precise external load setting. To validate the theoretical model, an ultrasonic dry coupling experimental platform was constructed. The experimental results show that applying an appropriate external load improves the acoustic coupling effect, and the higher the fractal dimension, the lower the load required to achieve ideal coupling. Compared to traditional roughness parameters, the fractal dimension significantly improves measurement stability, reducing the standard deviation by 79.3%. Using the portable dry coupling wheel probe for thickness reduction measurement and applying the fractal dimension method, the minimum load required for optimal coupling was determined. The actual measurement error was maintained within 3%, confirming the feasibility of dry coupling technology for damage detection. Therefore, this study provides theoretical support and a quantitative reference for the performance optimization of dry coupling ultrasonic testing systems.</div></div>","PeriodicalId":55506,"journal":{"name":"Applied Acoustics","volume":"244 ","pages":"Article 111174"},"PeriodicalIF":3.4,"publicationDate":"2026-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145618550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}