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The Evaluation of the sound insulation of Partition in Expanded Frequency Range

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Journal of Physical Science and Application 2013年第4期3卷 249-255页

作者： Nataliya Samoylenko Vitaliy Didkovskiy Faculty of Electronic National Technical University of Ukraine Kiev 03056 Ukraine

This paper reports on an evaluation of airborne sound insulation in a wider frequency range then is used in classical measurements. For analyzing sound insulation was used frequency range from 50 Hz to 10 kHz via standard range I00 Hz to 3,15 kHz. For four constructions with different structure was measured sound reduction index depend on frequency and calculated Weighted sound reduction index according to EN ISO 717-1. Then the results were compared. The measurements were made for samples of construction with different sizes. The results of measurements show how the size of sample influence on measured sound insulation. This article could be useful for specialist of architect acoustic and all who interest in sound insulation.

关键词： sound insulation airborne noise frequency range partition.

Optimization of sound Absorption and insulation Performances of a Dual-Cavity Resonant Micro-Perforated Plate

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Fluid Dynamics & Materials Processing 2022年第2期18卷 481-496页

作者： Wei Chen Zhaofeng Guo Hongda Feng Sheng Hu Ling Lu Chuanmin Chen Xiaowen Wu Hao Cao State Grid Hunan Electric Power Co. Ltd.Electric Power Research InstituteChangsha410000China State Grid Corporation of China Power Facilities Noise and Vibration Laboratory Changsha410000China North China Electric Power University Department of Environmental Science and EngineeringHebei Provincial Key Laboratory of Coal-Fired Power Station Flue Gas Multi-Pollution Cooperative ControlBaoding071003China North China Electric Power University Key Laboratory of Regional Energy System Optimization Ministry of EducationBeijing102206China

This study investigates a dual-cavity resonant composite sound-absorbing structure based on a micro-perforated *** the COMSOL impedance tube model,the effects of various structural parameters on sound absorption and sound insulation performances are *** show that the aperture of the micro-perforated plate has the greatest influence on the sound absorption coefficient;the smaller the aperture,the greater is this *** thickness of the resonance plate has the most significant influence on the sound insulation and resonance frequency;the greater the thickness,the wider the frequency domain in which sound insulation is *** addition,the effect of filling the structural cavity with porous foam ceramics has been studied,and it has been found that the porosity and thickness of the porous material have a significant effect on the sound absorption coefficient and sound insulation,while the pore size exhibits a limited influence.

关键词： Micro perforated plate double cavity compound resonance structure sound absorption coefficient sound insulation

EXPERIMENTAL STUDY OF ACOUSTICAL insulation OF CEMENT-BASED BOARD PREPARED WITH WASTE COCONUT COIR AND OIL PALM FIBERS

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Journal of Green Building 2021年第4期16卷 63-80页

作者： Pusit Lertwattanaruk Natt Makul Kanokwan Masuwan Faculty of Architecture and Planning Thammasat UniversityKlong LuangPathumthani 12121Thailand Faculty of Industrial Technology Phranakhon Rajabhat UniversityBangkhenBangkok 10220Thailand

Among the major challenges facing the modern era of technological and industrial advancements are pollution and exponentially growing energy *** continues to be a menace affecting different aspects of life such as health,productivity,and *** paper focuses on the elimination or reduction of sound pollution in buildings using cement-based boards made from pretreated coconut coir and oil palm fibers obtained from agricultural *** study includes an account of the preparation of fiber cement boards made from Portland cement Type 1,limestone powder,water,sand,and pretreated coconut coir and oil palm fibers at 5,10,15,and 20%by weight of powder materials,respectively,and a high-range water reducer in order to make sure that the natural materials would be spread in an even way throughout the *** insulation tests were performed as key indicators of the performance of the fiber cement *** was found that an increase in the proportion of natural materials resulted in fiber cement boards with decreased density,compressive strength,and flexural ***,in relation to both physical and mechanical performance,the boards incorporating coconut fibers were superior to those incorporating oil palm *** an increased proportion of natural fibers,sound insulation performance tended to *** boards prepared with coconut coir and oil palm fibers in this study yielded acceptable physical and mechanical properties and showed promise in relation to providing insulative protection against sound.

关键词： sound insulation fiber cement board mechanical properties coconut coir fiber oil palm fiber

Symplectic analysis for elastic wave propagation in two-dimensional cellular structures

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Acta Mechanica Sinica 2010年第5期26卷 711-720页

作者： Xiu-Hui Hou Zi-Chen Deng Jia-Xi Zhou Tie-Quan Liu Department of Engineering Mechanics Northwestern Polytechnical University Xi'an 710072 China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China

On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables and the wave propagation problem is then transformed into two-dimensional （2D） symplectic eigenvalue problems, where the extended Wittrick-Williams algorithm is used to ensure that no phase propagation eigenvalues are missed during computation. Three typical cellular structures, square, triangle and hexagon, are introduced to illustrate the unique feature of the symplectic algorithm in higher-frequency calculation, which is due to the conserved properties of the structure-preserving symplectic algorithm. On the basis of the dispersion relations and phase constant surface analysis, the band structure is shown to be insensitive to the material type at lower frequencies, however, much more related at higher frequencies. This paper also demonstrates how the boundary conditions adopted in the finite element modeling process and the structures＇ configurations affect the band structures. The hexagonal cells are demonstrated to be more efficient for sound insulation at higher frequencies, while the triangular cells are preferred at lower frequencies. No complete band gaps are observed for the square cells with fixed-end boundary conditions. The analysis of phase constant surfaces guides the design of 2D cellular structures where waves at certain frequencies do not propagate in specified directions. The findings from the present study will provide invaluable guidelines for the future application of cellular structures in sound insulation.

关键词： Cellular structures Symplectic analysis Dispersion relation - Phase constant surface sound insulation

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隔声现场测量的扬声器声源方法改进

声学技术 2005年第Z1期24卷 95-96页

作者：陈卫松刘嘉俊邱小军近代声学国家重点实验室南京大学声学研究所台湾永续工程顾问有限公司安徽师范大学

　　1引言　　隔声现场测量主要方法有交通噪声源现场测量和扬声器声源现场测量.现行国家标准和国际标准中[1],将扬声器声源放在测试现场离隔声构件一定距离并与隔声构件的中心轴成一定角度处,测量此时构件的隔声量作为该构件的现场隔声... 详细信息

　　1引言　　隔声现场测量主要方法有交通噪声源现场测量和扬声器声源现场测量.现行国家标准和国际标准中[1],将扬声器声源放在测试现场离隔声构件一定距离并与隔声构件的中心轴成一定角度处,测量此时构件的隔声量作为该构件的现场隔声量.标准规定扬声器发出声波与构件中心轴所成的角度为45°.扬声器噪声源的现场测量方法针对声波在某一角度入射时测得的隔卢效果,而现场噪声可视为半自由场入射,因而测量数据与现场声场条件下构件的实际隔声量存在差异.本文提出了扬声器声源现场测量的改进方案,采取扬卢器多角度放置进行现场测量再按角度求隔声量的平均值,实验结果与理论预测基本一致.这种改进测量方法受外界环境的影响较小,且实验测得的隔声量接近现场的实际隔声效果.　　……

关键词：隔声现场测量扬声器噪声源方法改进 sound insulation 隔声量隔声构件测量方法中心轴国家标准主要方法外界环境实验测声场条件声波理论预测国际标准隔声效果测量数据半自由场

Numerical Simulation and Experimental Study of Underwater Compound Structures Containing Honeycomb Interlayer

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International Journal of Plant Engineering and Management 2008年第4期13卷 181-190页

作者： LIU Zhi-hong SHENG Mei-ping WANG Min-qing College of Marine Engineering Northwestern Polytechnical University Xi'an Shaanxi 710072 P.R. China

Honeycomb interlayer structure sound wave transferring theory of infinite is introduced into the underwater noise control. Based on the layered elastic or viscoelastic medium, the sound insulation property of a normal incidence plane wave on underwater honeycomb interlayer structure is studied by using the method of the transfer matrix and percentage distribution of sound energy in As a particular kind of complex multilayered rubber compound structures, honeycomb different areas. compound structure has better sound insulation property than rubber interlayer with cylindrical cavities compound structure. Simulation results show that the property of rubber material has great effect on structural sound insulation. Soft and small Poisson＇ s ratio rubber can obviously improve sound insulation performance of the whole structure. Furthermore, the material property of the face layer of the honeycomb interlayer structure has greater effects on the insulation performance. To validate the theoretical analysis, large samples of freedom-field measurement of honeycomb sandwich compound structure is carried out in the anechoic water tank of our university. The measurement result is in good agreement with the theoretical prediction.

关键词： sound insulation honeycomb interlayer underwater compound structure

Analysis of soundproof Technology of Assembled Steel Structure Houses

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Journal of World Architecture 2023年第5期7卷 66-71页

作者： Jing Sun Chongqing Energy College Chongqing 402260China

The problem of noise has always been highlighted in assembled steel structure ***,it is necessary to use effective soundproof measures where steel beams intersect with the reserved line pipe openings,doors,windows,elevator shafts,and other *** this paper,we will investigate the areas with subpar soundproof performance in an assembled steel structure residential project and propose suitable noise control measures to address this issue.

关键词： Assembled steel structure Residential engineering sound insulation Construction technology Online publication:October 25,2023

丁基橡胶特性参数对其隔声性能影响的数值模拟分析

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丁基橡胶特性参数对其隔声性能影响的数值模拟分析