Article
Acoustics
Heming Li, Jinwu Wu, Shanlin Yan, Qibo Mao
Summary: This paper presents the design and development of micro-perforated panel (MPP) absorbers with a variable section partition to solve the broadband sound absorption problem. Three types of MPP absorbers were developed based on the cavity, and their absorption characteristics were investigated and optimized. Experimental results show that the optimized absorbers have superior broadband sound absorption performance compared to conventional MPP absorbers.
Article
Physics, Applied
Baozhu Cheng, Xinyu Guo, Nansha Gao, Hong Hou
Summary: This paper proposes the methods of porous material filling and micro-perforated plate embedding to design a perfect sound absorber at different frequencies using the under-loss Helmholtz resonator. The theoretical calculation models of the sound absorption coefficients are constructed and verified. Experimental results show the effectiveness of the designed acoustic absorbers, providing reference for low-frequency broadband noise attenuation designs.
MODERN PHYSICS LETTERS B
(2022)
Article
Engineering, Mechanical
Xiyue Ma, Daniil Yurchenko, Kean Chen, Lei Wang, Yang Liu, Kai Yang
Summary: This paper investigates the performance of a new type of sound-controlled micro-perforated panel absorber, which achieves wide-band perfect low-frequency sound absorption using a point force controlled backing panel. The theoretical model is established and the influence of structure size and point force position on sound absorption performance is explored. Experimental tests are conducted to validate the findings, and the physical mechanisms of active control are analyzed. A simplified error sensing strategy is also constructed. The results show that locating the point force at the center or using a relatively small sized absorber can achieve perfect sound absorption in a wide controllable bandwidth.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Acoustics
Jingfeng Ning, Qian Geng, M. P. Arunkumar, Yueming Li
Summary: A light composite absorber with a micro-perforated sandwich panel filled with thin porous materials is proposed in this study to achieve a wide absorption bandwidth. The theoretical model derived by the transfer matrix method is in good agreement with experimental results, showing better performance compared to other absorbers. The absorption mechanism and the effects of internal components on absorption performance are analyzed in detail.
Article
Acoustics
H. Hoppen, F. Langfeldt, W. Gleine, O. von Estorff
Summary: This paper presents the acoustical properties and theoretical descriptions of a Helmholtz resonator with an integrated cantilever. The resonator design allows for a second resonance frequency, resulting in an additional frequency region with high sound absorption properties. Analytical models are used to calculate the resonance frequencies and absorption coefficient of the system, which have been validated through finite element simulations and experimental measurements. The study concludes that geometric parameters significantly influence the resonance frequencies and that the coupled resonator system exhibits a broader sound absorption performance.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Mechanical
Xiang Liu, Chunqi Wang, Yumin Zhang, Lixi Huang
Summary: An investigation into a smart micro-perforated panel aims to enhance the sound absorption performance of MPP absorbers at low frequencies, utilizing a combination of mechanical damping, electrical shunt damping, and Helmholtz resonance. Different multimode shunt design methods are explored to intensify panel vibration and improve sound absorption, with absorption peaks induced by electromechanical coupling found at frequencies lower than the MPP's Helmholtz resonance frequency.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Acoustics
Xin Li, Bilong Liu, Daoqing Chang
Summary: An acoustic impedance compound structure composed of perforated panel resonator (PPR) and porous sound absorbing material (PSAM) is designed to enhance sound absorption for low-to-mid frequencies. By introducing a porous sound absorbing material component into the PPR component, a matched acoustic impedance is achieved, resulting in effective wide-band sound absorption. Experimental results show that the designed composite structure PPR-PSAM has an average sound absorption coefficient of more than 0.89 in the frequency range of 200-1600 Hz.
Article
Acoustics
Jiayu Wang, Gareth J. Bennett
Summary: This paper presents an optimised, multi-chamber, micro-perforated panel absorber (MC-MPPA) with micro-perforated adjoining panels. By employing a graph-theory-based method, a model for multi-chamber MPPAs can be developed, allowing the optimisation of different geometric parameters to achieve a broadband frequency response with a shallow cavity. Experimental results show that the MC-MPPA achieves an overall absorption coefficient of 0.83 in the frequency range of 660 Hz to 2 kHz and a depth-to-wavelength ratio of 20, making it a deeply subwavelength absorber.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Acoustics
K. Mahesh, R. S. Mini
Summary: The integration of Helmholtz resonators with MPP in series and parallel arrangements has shown a reduction in absorber thickness and achieved efficient low frequency broadband sound absorption. The performance of the absorber with a specific frequency band width is superior when the units are arranged in combination compared to successive arrangements of the same units.
Article
Acoustics
Xiyue Ma, Kean Chen, Lei Wang, Yang Liu, Shaohu Ding
Summary: This paper presents a theoretical investigation on actively controlling the low frequency sound absorption of large-sized micro-perforated panel absorber (MPPA) by using point source placed in the cavity. Results show that the sound absorption performance can be significantly improved, with the optimal position of the point source at the central of the cavity section. The control mechanism is to enhance the Helmholtz type resonant absorption.
Article
Physics, Multidisciplinary
Ting Li, Feng-Min Wu, Tong-Tao Zhang, Jun-Jun Wang, Bin Yang, Dong Zhang
Summary: This study proposes a novel broadband low-frequency ventilation absorber with a rough neck to improve the unsatisfactory low-frequency sound absorption effect of Helmholtz resonator. The introduction of roughness in the neck of the absorber effectively changes the shape of the neck and reduces the resonant frequency. Experimental and simulation results show that the absorber with roughness in the neck achieves a lower resonant peak frequency and higher absorption coefficient compared to the absorber without roughness. Furthermore, the study designs a broadband low-frequency ventilation absorber with a rough neck composed of eight absorption units, which achieves high absorption coefficients and consecutive absorption peaks in a wide frequency range. The research provides valuable insights into the design and optimization of efficient low-frequency acoustic absorbers.
ACTA PHYSICA SINICA
(2023)
Article
Mechanics
Xuewei Liu, Chenlei Yu, Fengxian Xin
Summary: The study introduces a novel sound absorber that combines low-frequency and broadband absorption functions by using gradually perforated porous materials and a Helmholtz resonant cavity. Theoretical and finite element models were developed to analyze the sound absorption mechanisms and factors influencing performance.
COMPOSITE STRUCTURES
(2021)
Article
Acoustics
Cong Gao, Chuandeng Hu, Bo Hou, Xianli Zhang, Shanshan Li, Weijia Wen
Summary: In this study, a silencer comprising of decoupled annular Helmholtz resonators (AHR) is designed for low frequency sound absorption. Theoretical model based on the temporal coupled mode theory (TCMT) is used to reveal the working mechanism. To improve feasibility and reduce installation space, an arc-shaped Helmholtz resonator (ASHR) is proposed for optimization. Both structures are experimentally verified to have good feasibility for practical application, with the AHR silencer achieving >95% sound absorption coefficient from 690 Hz to 1350 Hz and the ASHR silencer generating four effective peak absorption peaks over the range 570-1720 Hz.
Article
Acoustics
Xiyue Ma, Lei Wang, Kean Chen, Xuhua Tian
Summary: This paper presents a comprehensive investigation on the passive and active low frequency sound absorption performance of the finite and large sized micro-perforated panel absorber (FLS-MPPA) for oblique incidence excitation (OIE). The theoretical model of the FLS-MPPA is established and validated, and the passive sound absorption performance and physical mechanisms are explored. The active control performance and physical mechanism of sound absorption improvement are also analyzed.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Mechanical
Weiping Yang, Yatsze Choy, Ying Li
Summary: In this study, the sound absorption performance of a wavy micro-perforated panel absorber (WMPPA) is investigated. The WMPPA exhibits promising potential for the control of low-frequency and broadband noise, with improved sound absorption performance at lower frequencies and additional absorption peaks in the middle to high-frequency range. The study validates the proposed model and uncovers the acoustical properties and performance enhancements of the WMPPA.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Acoustics
Cailiang Zhang, Zhihui Lai, Zhisheng Tu, Hanqiu Liu, Yong Chen, Ronghua Zhu
Summary: This paper proposes two single-parameter-adjusting SR models to optimize the output performance of SR systems. The effects of the proposed models on SR output under different parameters and signals are investigated through numerical simulations, and their feasibility is verified through experimental results. The research results are of great significance for guiding the design of tri-stable SR models and the application of SR-based signal processing in the context of big data.
Article
Acoustics
Shaoqiong Yang, Hao Chang, Yanhui Wang, Ming Yang, Tongshuai Sun
Summary: In this study, a suspension system based on phononic crystals is designed for vibration isolation of acoustic loads in underwater gliders. The vibration properties of the phononic crystals and the effects of physical parameters on the underwater attenuation zones are investigated. Vibration tests show that the phononic crystal suspension system has a stable vibration isolation effect in the frequency range of 120-5000 Hz.
Article
Acoustics
Xuebin Zhang, Jun Zhang, Tao Liu, Ning Hu
Summary: This study proposes a tunable metamaterial beam to isolate flexural waves. A genetic algorithm-based size optimization is used to obtain a broad low-frequency bandgap. The tunability of the beam is achieved by attaching different numbers of permanent magnets to change the mass of the resonators. Additionally, ultra-broadband flexural wave attenuation is achieved by forming a gradient metamaterial beam based on the rainbow effect. Numerical and experimental results confirm the good flexural wave attenuation ability of the proposed beam.
Article
Acoustics
Luca Rapino, Francesco Ripamonti, Samanta Dallasta, Simone Baro, Roberto Corradi
Summary: This paper presents a method for simulating tyre/road noise using equivalent monopoles, including the synthesis of monopoles through an inverse problem approach and the use of an ISO 10844 road replica for laboratory testing. The method combines acoustic finite element models and numerical simulations of vehicles, and the results are validated by comparing them with measured data.
Article
Acoustics
Xiaoyan Zhu, Tin Oberman, Francesco Aletta
Summary: This paper explores the definition of acoustical heritage and proposes a multidimensional definition based on interviews with experts and detailed analysis of the data.
Article
Acoustics
Faeez Masurkar, Saurabh Aggarwal, Zi Wen Tham, Lei Zhang, Feng Yang, Fangsen Cui
Summary: This research focuses on estimating the elastic constants of orthotropic laminates using ultrasonic guided waves and inverse machine learning models. The results show that this approach has the potential to accurately predict the elastic constants of a material and reduce computational time.
Article
Acoustics
Feng Xiao, Haiquan Liu, Jia Lu
Summary: Diagnostic methods for cardiovascular disease based on heart sound classification have been widely studied due to their noninvasiveness, low-cost, and high efficiency. However, existing research often faces challenges such as the nonstationarity and complexity of heart sound signals, leading to limited capability of neural networks to extract discriminative features. To address these issues, this study proposes a novel convolutional neural network that combines 1D convolution and 2D convolution, and introduces an attention mechanism to enhance feature extraction capability. The study also explores the advantages and disadvantages of combining deep learning features with manual features, and adopts an evolving fuzzy system for decision-making interpretability.
Article
Acoustics
Hong Xu, Zhengyao He, Qiang Shi, Yushi Wang, Bo Zhang
Summary: This paper presents the development of a directional segmented ring transmitting transducer that can radiate sound waves in any horizontal region. The study focuses on the structure of the segmented ring transducer, its radiation sound field characteristics, and the beam pattern control method based on modal synthesis. The authors propose orthogonal beam pattern functions for adjusting steering angles and establish a three-dimensional finite element model to simulate the transmitting beam patterns. Experimental measurements and tests validate the effectiveness of the proposed transducer, showcasing its ability to steer the beam patterns to different directions.
Article
Acoustics
Jirui Yang, Shefeng Yan, Di Zeng, Gang Tan
Summary: This paper proposes an improved domain adaptation framework, self-supervised learning minimax entropy, to enhance the recognition performance of underwater target recognition models. The experimental results demonstrate that applying domain adaptation methods can effectively improve the recognition accuracy of the models under various marine conditions.
Article
Acoustics
Zonghan Sun, Jie Tian, Yuhang Zheng, Xiaocheng Zhu, Zhaohui Du, Hua Ouyang
Summary: This paper analyzes the noise reduction method of installing a sinusoidal-shaped inlet duct on a cooling fan through theoretical and experimental analysis of the acoustic mode modulation. The study establishes the correlation between the free field noise and acoustic mode of the fan rotor and the unsteady forces on the rotor blade surface. The results show that the sinusoidal-shaped inlet duct achieves greater noise reduction compared to a straight duct, especially at the blade passing frequency and its first harmonic.
Article
Acoustics
Min Li, Rumei Han, Hui Xie, Ruining Zhang, Haochen Guo, Yuan Zhang, Jian Kang
Summary: This study is part of a global collaboration to translate and standardise soundscape research. A reliable questionnaire for soundscape characterisation in Mandarin Chinese was developed and validated. The study found that salient sound sources become the focus of attention for individuals in urban open spaces, and the perception is also influenced by the acoustic characteristics of the soundscape. Certain types of sound sources play a more important role in soundscape perception.
Article
Acoustics
Arezoo Talebzadeh, Dick Botteldooren, Timothy Van Renterghem, Pieter Thomas, Dominique Van de Velde, Patricia De Vriendt, Tara Vander Mynsbrugge, Yuanbo Hou, Paul Devos
Summary: This study proposes a sound selection methodology to enhance the soundscape in nursing homes and reduce BPSD by analyzing sound characteristics and recognition methods. The results highlight the sound characteristics that lead to positive responses, while also pointing out the need for further studies to understand which sounds are most suitable for people with dementia.
Article
Acoustics
Yang Yang, Yongxin Yang, Zhigang Chu
Summary: This paper introduces a grid-free compressive beamforming method compatible with arbitrary linear microphone arrays, and demonstrates the correctness and superiority of the proposed method through examples. Monte Carlo simulations are performed to reveal the effects of source coherence, source separation, noise, and number of snapshots.
Article
Acoustics
Sukru Selim Calik, Ayhan Kucukmanisa, Zeynep Hilal Kilimci
Summary: Computer-Aided Language Learning (CALL) is growing rapidly due to the importance of acquiring proficiency in multiple languages for effective communication. In the field of CALL, the detection of mispronunciations is vital for non-native speakers. This research introduces a novel framework using audio-centric transformer models to detect mispronunciations in Arabic phonemes. The results demonstrate that the UNI-SPEECH transformer model yields notable classification outcomes in Arabic phoneme mispronunciation detection. The comprehensive comparison of these transformer models provides valuable insights and guidance for future investigations in this domain.
Article
Acoustics
Yi-Yang Ni, Fei-Yun Wu, Hui-Zhong Yang, Kunde Yang
Summary: This paper proposes an improved method for compressive sensing by introducing a self training dictionary scheme and a CS reconstruction method based on A*OLS, which enhances the sparse representation performance of propeller signals.