Zonglin Li^1,2, Zhenyu Gao², Yijun Liu^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.3, pp. 2159-2175, 2024, DOI:10.32604/cmes.2023.030920

Abstract The boundary element method (BEM) is a popular method for solving acoustic wave propagation problems, especially those in exterior domains, owing to its ease in handling radiation conditions at infinity. However, BEM models must meet the requirement of 6–10 elements per wavelength, using the conventional constant, linear, or quadratic elements. Therefore, a large storage size of memory and long solution time are often needed in solving higher-frequency problems. In this work, we propose two new types of enriched elements based on conventional constant boundary elements to improve the computational efficiency of the 2D acoustic BEM. The first one uses a… More > Graphic Abstract

Yunru Wu¹, Xiangbo Liu¹, Haibo Huang^1,2,*, Yudong Wu¹, Weiping Ding^1,2, Mingliang Yang^1,2,*

Sound & Vibration, Vol.57, pp. 73-95, 2023, DOI:10.32604/sv.2023.044601

Abstract Vehicle interior noise has emerged as a crucial assessment criterion for automotive NVH (Noise, Vibration, and Harshness). When analyzing the NVH performance of the vehicle body, the traditional SEA (Statistical Energy Analysis) simulation technology is usually limited by the accuracy of the material parameters obtained during the acoustic package modeling and the limitations of the application conditions. In order to effectively solve these shortcomings, based on the analysis of the vehicle noise transmission path, a multi-level objective decomposition architecture of the interior noise at the driver’s right ear is established. Combined with the data-driven method, the ResNet neural network model… More >

Haifeng Lin^1,2, Xiangfeng Liu², Chen Chen², Zhibo Liu², Dexin Zhao³, Yiwen Zhang⁴, Weizhuang Li⁴, Mingsheng Cao^5,6,*

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 939-956, 2024, DOI:10.32604/cmes.2023.028656

Abstract Identifying a device and detecting a change in its position is critical for secure devices management in the Internet of Things (IoT). In this paper, a device management system is proposed to track the devices by using audio-based location distinction techniques. In the proposed scheme, traditional cryptographic techniques, such as symmetric encryption algorithm, RSA-based signcryption scheme, and audio-based secure transmission, are utilized to provide authentication, non-repudiation, and confidentiality in the information interaction of the management system. Moreover, an audio-based location distinction method is designed to detect the position change of the devices. Specifically, the audio frequency response (AFR) of several… More >

Lingwen Jiang¹, Mingsong Zou^2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09669

Abstract Acoustic radiation and propagation characteristics of underwater elastic structures are an organic whole, which should be considered comprehensively. Based on the three-dimensional sono-elasticity theory of ships, the integrated calculation method of acoustic radiation and propagation in ocean environment is realized by using the simple source boundary integral equation. The correctness and accuracy of the method are verified by a series of examples. Based on the domestic supercomputer platform, the parallel transformation of the algorithm is completed, and the two-level multi-core parallel is realized, which greatly improves the computing efficiency. The application of acoustic radiation calculation in composite structures is carried… More >

Menghui Liang¹, Changjun Zheng^1,*, Yongbin Zhang¹, Chuanxing Bi¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09605

Abstract This paper presents an accurate and efficient indirect boundary element method (IBEM) accelerated by the fast multipole algorithm (FMA)for the design sensitivity analysis of large-scale thin-body acoustic problems above an infinite impedance plane. The non-uniqueness issue of the IBEM in solving exterior acoustic problems is avoided by applying a hybrid combination of single- and double-layer potentials. The half-space impedance Green’s function which involves an image complex line source and is valid for both mass-like and spring-like impedance plane is employed to involve the sound-absorbing effect of the ground surface. Explicit evaluation formulations of the singular boundary integrals are derived and… More >

Ruoyan Li^1,2, Yijun Liu^1,*, Wenjing Ye²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.09472

Abstract The boundary element method (BEM) for acoustic problems is a numerical method based on solving the discretized boundary integral equation (BIE) corresponding to the Helmholtz equation. A fast direct BEM for 3D acoustic problems is proposed in this paper, which is more suitable for broadband acoustic simulation of complex structures, such as in the design and analysis of acoustic metamaterials. The main idea of the fast direct solver is based on the hierarchical off-diagonal low-rank (HODLR) matrix, randomized interpolative decomposition and fast matrix inversion formula. Several numerical examples in solving both interior and exterior acoustic problems are presented in this… More >

Dan Li¹, Jie Wang¹, Haibo Chen^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.4, pp. 1-2, 2023, DOI:10.32604/icces.2023.09139

Abstract In practical vibro-acoustic problems, the external excitation normally contains a certain frequency band structure [1]. Therefore, it is needed to perform optimization under frequency band analysis. For sound radiation problems caused by structural vibration, a topology optimization method for structural materials is proposed based on the acoustic-vibration coupling analysis [2-6] and the frequency-band matrix interpolation method [7,8]. By combining the advantages of FEM and BEM in structural and acoustic field analysis, the accurate solution of the acoustic-vibration coupling problem is achieved. The structural material interpolation model is established using the solid isotropic material with penalization (SIMP) method, and the topological… More >

Haoyi Cheng¹, Jingwen Guo¹, Wenjing Ye^1.*, Xin Zhang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.2, pp. 1-1, 2023, DOI:10.32604/icces.2023.09237

Abstract With their thin thicknesses and unprecedent wave manipulation capabilities, acoustic metasurfaces have a great potential to be applied in a wide range of applications. Most existing metasurfaces are passive devices. Although passive devices are easy to implement and consume no energy, one major shortcoming of passive devices is their fixed and limited functionality, which greatly limits their application scope. To increase the functionalities of a metasurface and yet still maintain its passivity, we propose to use the wave frequency as a tuning freedom to realize multiple functionalities in one single passive device. Specifically, the passive metasurface will be designed to… More >

Yanming Xu^1,2, Leilei Chen^1,2,*, Haojie Lian³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.26, No.1, pp. 1-1, 2023, DOI:10.32604/icces.2023.010581

Abstract An isogeometric coupling algorithm based on the finite element method and the boundary element method (IGA-FEM/BEM) is proposed for the simulation of acoustic fluid-structure interaction and structuralacoustic topology optimization using the direct differentiation method. The geometries are constructed from triangular control meshes through Loop subdivision scheme. The effect of sound-absorbing materials on the acoustic response is characterized by acoustic impedance boundary conditions. The optimization problem is formulated in the framework of Solid Isotropic Material with Penalization methods and the sound absorption coefficients on elements are selected as design variables. Numerical examples are presented to demonstrate the validity and efficiency of… More >

Roman Vinokur^*

Sound & Vibration, Vol.57, pp. 1-13, 2023, DOI:10.32604/sv.2023.041784

Abstract The loss factors and their effects on the magnitude and frequency of resonance peaks in various mechanical systems are reviewed for acoustic, vibration, and vibration fatigue applications. The main trends and relationships were obtained for linear mechanical models with hysteresis damping. The well-known features (complex module of elasticity, total loss factor, etc.) are clarified for practical engineers and students, and new results are presented (in particular, for 2-DOF in-series models with hysteresis friction). The results are of both educational and practical interest and may be applied for NVH analysis and testing, mechanical and aeromechanical design, and noise and vibration control… More >