Effect of Thickness, Density and Cavity Depth on the Sound Absorption Properties of Wool Boards
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Acoustical and Optical Radiation Pressures and the Development of Single Beam Acoustical Tweezers Jean-Louis Thomas, Régis Marchiano, Diego Baresch
Acoustical and optical radiation pressures and the development of single beam acoustical tweezers Jean-Louis Thomas, Régis Marchiano, Diego Baresch To cite this version: Jean-Louis Thomas, Régis Marchiano, Diego Baresch. Acoustical and optical radiation pressures and the development of single beam acoustical tweezers. Journal of Quantitative Spectroscopy and Radiative Transfer, Elsevier, 2017, 195, pp.55-65. 10.1016/j.jqsrt.2017.01.012. hal-01438774 HAL Id: hal-01438774 https://hal.archives-ouvertes.fr/hal-01438774 Submitted on 18 Jan 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Acoustical and optical radiation pressures and the development of single beam acoustical tweezers Jean-Louis Thomasa,∗, R´egisMarchianob, Diego Barescha,b aSorbonne Universit´es,UPMC Univ Paris 06, CNRS UMR 7588, Institut des NanoSciences de Paris, 4 place Jussieu, Paris, France bSorbonne Universit´es,UPMC Univ Paris 06, CNRS UMR 7190, Institut Jean le Rond d'Alembert, 4 place Jussieu, Paris, France Abstract Studies on radiation pressure in acoustics and optics have enriched one an- other and have a long common history. Acoustic radiation pressure is used for metrology, levitation, particle trapping and actuation. However, the dexter- ity and selectivity of single-beam optical tweezers are still to be matched with acoustical devices. -
The Standing Acoustic Wave Principle Within the Frequency Analysis Of
inee Eng ring al & ic d M e e d Misun, J Biomed Eng Med Devic 2016, 1:3 m i o c i a B l D f o e v DOI: 10.4172/2475-7586.1000116 l i a c n e r s u o Journal of Biomedical Engineering and Medical Devices J ISSN: 2475-7586 Review Article Open Access The Standing Acoustic Wave Principle within the Frequency Analysis of Acoustic Signals in the Cochlea Vojtech Misun* Department of Solid Mechanics, Mechatronics and Biomechanics, Brno University of Technology, Brno, Czech Republic Abstract The organ of hearing is responsible for the correct frequency analysis of auditory perceptions coming from the outer environment. The article deals with the principles of the analysis of auditory perceptions in the cochlea only, i.e., from the overall signal leaving the oval window to its decomposition realized by the basilar membrane. The paper presents two different methods with the function of the cochlea considered as a frequency analyzer of perceived acoustic signals. First, there is an analysis of the principle that cochlear function involves acoustic waves travelling along the basilar membrane; this concept is one that prevails in the contemporary specialist literature. Then, a new principle with the working name “the principle of standing acoustic waves in the common cavity of the scala vestibuli and scala tympani” is presented and defined in depth. According to this principle, individual structural modes of the basilar membrane are excited by continuous standing waves of acoustic pressure in the scale tympani. Keywords: Cochlea function; Acoustic signals; Frequency analysis; The following is a description of the theories in question: Travelling wave principle; Standing wave principle 1. -
Nuclear Acoustic Resonance Investigations of the Longitudinal and Transverse Electron-Lattice Interaction in Transition Metals and Alloys V
NUCLEAR ACOUSTIC RESONANCE INVESTIGATIONS OF THE LONGITUDINAL AND TRANSVERSE ELECTRON-LATTICE INTERACTION IN TRANSITION METALS AND ALLOYS V. Müller, G. Schanz, E.-J. Unterhorst, D. Maurer To cite this version: V. Müller, G. Schanz, E.-J. Unterhorst, D. Maurer. NUCLEAR ACOUSTIC RESONANCE INVES- TIGATIONS OF THE LONGITUDINAL AND TRANSVERSE ELECTRON-LATTICE INTERAC- TION IN TRANSITION METALS AND ALLOYS. Journal de Physique Colloques, 1981, 42 (C6), pp.C6-389-C6-391. 10.1051/jphyscol:19816113. jpa-00221175 HAL Id: jpa-00221175 https://hal.archives-ouvertes.fr/jpa-00221175 Submitted on 1 Jan 1981 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. JOURNAL DE PHYSIQUE CoZZoque C6, suppZe'ment au no 22, Tome 42, de'cembre 1981 page C6-389 NUCLEAR ACOUSTIC RESONANCE INVESTIGATIONS OF THE LONGITUDINAL AND TRANSVERSE ELECTRON-LATTICE INTERACTION IN TRANSITION METALS AND ALLOYS V. Miiller, G. Schanz, E.-J. Unterhorst and D. Maurer &eie Universit8G Berlin, Fachbereich Physik, Kiinigin-Luise-Str.28-30, 0-1000 Berlin 33, Gemany Abstract.- In metals the conduction electrons contribute significantly to the acoustic-wave-induced electric-field-gradient-tensor (DEFG) at the nuclear positions. Since nuclear electric quadrupole coupling to the DEFG is sensi- tive to acoustic shear modes only, nuclear acoustic resonance (NAR) is a par- ticularly useful tool in studying the coup1 ing of electrons to shear modes without being affected by volume dilatations. -
Acoustic Wave Propagation in Rivers: an Experimental Study Thomas Geay1, Ludovic Michel1,2, Sébastien Zanker2 and James Robert Rigby3 1Univ
Acoustic wave propagation in rivers: an experimental study Thomas Geay1, Ludovic Michel1,2, Sébastien Zanker2 and James Robert Rigby3 1Univ. Grenoble Alpes, CNRS, Grenoble INP, GIPSA-lab, 38000 Grenoble, France 2EDF, Division Technique Générale, 38000 Grenoble, France 5 3USDA-ARS National Sedimentation Laboratory, Oxford, Mississippi, USA Correspondence to: Thomas Geay ([email protected]) Abstract. This research has been conducted to develop the use of Passive Acoustic Monitoring (PAM) in rivers, a surrogate method for bedload monitoring. PAM consists in measuring the underwater noise naturally generated by bedload particles when impacting the river bed. Monitored bedload acoustic signals depend on bedload characteristics (e.g. grain size 10 distribution, fluxes) but are also affected by the environment in which the acoustic waves are propagated. This study focuses on the determination of propagation effects in rivers. An experimental approach has been conducted in several streams to estimate acoustic propagation laws in field conditions. It is found that acoustic waves are differently propagated according to their frequency. As reported in other studies, acoustic waves are affected by the existence of a cutoff frequency in the kHz region. This cutoff frequency is inversely proportional to the water depth: larger water depth enables a better propagation of 15 the acoustic waves at low frequency. Above the cutoff frequency, attenuation coefficients are found to increase linearly with frequency. The power of bedload sounds is more attenuated at higher frequencies than at low frequencies which means that, above the cutoff frequency, sounds of big particles are better propagated than sounds of small particles. Finally, it is observed that attenuation coefficients are variable within 2 orders of magnitude from one river to another. -
In-Situ Attenuation Corrections for Radiation Force Measurements of High Frequency Ultrasound with a Conical Target
Volume 111, Number 6, November-December 2006 Journal of Research of the National Institute of Standards and Technology [J. Res. Natl. Inst. Stand. Technol. 111, 435-442 (2006)] In-situ Attenuation Corrections for Radiation Force Measurements of High Frequency Ultrasound With a Conical Target Volume 111 Number 6 November-December 2006 Steven E. Fick Radiation force balance (RFB) measure- Key words: attenuation correction; coni- ments of time-averaged, spatially-integrat- cal target; in-situ attenuation; power meas- National Institute of Standards ed ultrasound power transmitted into a urement; radiation force balance; radiation and Technology, reflectionless water load are based on pressure; ultrasonic power; ultrasound Gaithersburg, MD 20899 measurements of the power received by power. the RFB target. When conical targets are used to intercept the output of collimated, and circularly symmetric ultrasound sources operating at frequencies above a few Dorea Ruggles megahertz, the correction for in-situ atten- uation is significant, and differs signifi- cantly from predictions for idealized cir- School of Architecture, Accepted: November 7, 2006 cumstances. Empirical attenuation correc- Program in Architectural tion factors for a 45° (half-angle) absorp- Acoustics, tive conical RFB target have been deter- Rensselaer Polytechnic Institute, mined for 24 frequencies covering the 5 Troy, NY 12180 MHz to 30 MHz range. They agree well with previously unpublished attenuation calibration factors determined in 1994 for [email protected] a similar target. Available online: http://www.nist.gov/jres 1. Introduction stances, the inertia of the target causes it to effectively integrate pulses into the corresponding steady-state Radiation pressure [1-13] has been employed in a force. -
Springer Handbook of Acoustics
Springer Handbook of Acoustics Springer Handbooks provide a concise compilation of approved key information on methods of research, general principles, and functional relationships in physi- cal sciences and engineering. The world’s leading experts in the fields of physics and engineering will be assigned by one or several renowned editors to write the chapters com- prising each volume. The content is selected by these experts from Springer sources (books, journals, online content) and other systematic and approved recent publications of physical and technical information. The volumes are designed to be useful as readable desk reference books to give a fast and comprehen- sive overview and easy retrieval of essential reliable key information, including tables, graphs, and bibli- ographies. References to extensive sources are provided. HandbookSpringer of Acoustics Thomas D. Rossing (Ed.) With CD-ROM, 962 Figures and 91 Tables 123 Editor: Thomas D. Rossing Stanford University Center for Computer Research in Music and Acoustics Stanford, CA 94305, USA Editorial Board: Manfred R. Schroeder, University of Göttingen, Germany William M. Hartmann, Michigan State University, USA Neville H. Fletcher, Australian National University, Australia Floyd Dunn, University of Illinois, USA D. Murray Campbell, The University of Edinburgh, UK Library of Congress Control Number: 2006927050 ISBN: 978-0-387-30446-5 e-ISBN: 0-387-30425-0 Printed on acid free paper c 2007, Springer Science+Business Media, LLC New York All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC New York, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. -
About Possibility of Using the Reverberation Phenomenon in the Defectoscopy Field and the Stress-Strain State Evaluation of Solids
International Journal of Applied Engineering Research ISSN 0973-4562 Volume 12, Number 23 (2017) pp. 13122-13126 © Research India Publications. http://www.ripublication.com About Possibility of using the Reverberation Phenomenon in the Defectoscopy Field and the Stress-Strain State Evaluation of Solids Petr N. Khorsov1, Anna A. Demikhova1* and Alexander A. Rogachev2 1 National Research Tomsk Polytechnic University, 30, Lenina Avenue, 634050, Tomsk, Russia. 2 Francisk Skorina Gomel State University, 104, Sovetskaya str., 246019, Gomel, Republic of Belarus. Abstract multiple reflections from natural and artificial interference [6- 8]. The work assesses the possibilities of using the reverberation phenomenon for defectiveness testing and stress-strain state of The reverberation phenomenon is also used in the solid dielectrics on the mechanoelectrical transformations mechanoelectrical transformations (MET) method for method base. The principal reverberation advantage is that investigation the defectiveness and stress-strain state (SSS) of excitation acoustic wave repeatedly crosses the dielectric composite materials [9]. The essence of the MET- heterogeneities zones of testing objects. This causes to method is that the test sample is subjected pulse acoustic distortions accumulation of wave fronts which is revealed in excitement, as a result of which an acoustic wave propagates the response parameters. A comparative responses analysis in it. Waves fronts repeatedly reflecting from the boundaries from the sample in uniaxial compression conditions at crosse defective and local inhomogeneities zones. different loads in two areas of responses time realizations was Part of the acoustic energy waves converted into made: deterministic ones in the initial intervals and pseudo- electromagnetic signal on the MET sources. Double electrical random intervals in condition of superposition of large layers at the boundaries of heterogeneous materials, as well as numbers reflected acoustic waves. -
Recent Advances in the Sound Insulation Properties of Bio-Based Materials
PEER-REVIEWED REVIEW ARTICLE bioresources.com Recent Advances in the Sound Insulation Properties of Bio-based Materials Xiaodong Zhu,a,b Birm-June Kim,c Qingwen Wang,a and Qinglin Wu b,* Many bio-based materials, which have lower environmental impact than traditional synthetic materials, show good sound absorbing and sound insulation performances. This review highlights progress in sound transmission properties of bio-based materials and provides a comprehensive account of various multiporous bio-based materials and multilayered structures used in sound absorption and insulation products. Furthermore, principal models of sound transmission are discussed in order to aid in an understanding of sound transmission properties of bio-based materials. In addition, the review presents discussions on the composite structure optimization and future research in using co-extruded wood plastic composite for sound insulation control. This review contributes to the body of knowledge on the sound transmission properties of bio-based materials, provides a better understanding of the models of some multiporous bio-based materials and multilayered structures, and contributes to the wider adoption of bio-based materials as sound absorbers. Keywords: Bio-based material; Acoustic properties; Sound transmission; Transmission loss; Sound absorbing; Sound insulation Contact information: a: Key Laboratory of Bio-based Material Science and Technology (Ministry of Education), Northeast Forestry University, Harbin 150040, China; b: School of Renewable Natural Resources, LSU AgCenter, Baton Rouge, Louisiana; c: Department of Forest Products and Biotechnology, Kookmin University, Seoul 136-702, Korea. * Corresponding author: [email protected] (Qinglin Wu) INTRODUCTION Noise reduction is a must, as noise has negative effects on physiological processes and human psychological health. -
Recent Advances in Acoustic Metamaterials for Simultaneous Sound Attenuation and Air Ventilation Performances
Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 27 July 2020 doi:10.20944/preprints202007.0521.v2 Peer-reviewed version available at Crystals 2020, 10, 686; doi:10.3390/cryst10080686 Review Recent advances in acoustic metamaterials for simultaneous sound attenuation and air ventilation performances Sanjay Kumar1,* and Heow Pueh Lee1 1 Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore; [email protected] * Correspondence: [email protected] (S.K.); [email protected] (H.P.Lee) Abstract: In the past two decades, acoustic metamaterials have garnered much attention owing to their unique functional characteristics, which is difficult to be found in naturally available materials. The acoustic metamaterials have demonstrated to exhibit excellent acoustical characteristics that paved a new pathway for researchers to develop effective solutions for a wide variety of multifunctional applications such as low-frequency sound attenuation, sound wave manipulation, energy harvesting, acoustic focusing, acoustic cloaking, biomedical acoustics, and topological acoustics. This review provides an update on the acoustic metamaterials' recent progress for simultaneous sound attenuation and air ventilation performances. Several variants of acoustic metamaterials, such as locally resonant structures, space-coiling, holey and labyrinthine metamaterials, and Fano resonant materials, are discussed briefly. Finally, the current challenges and future outlook in this emerging field -
Notes on Absorption and Impedance Measurements
Notes on Absorption and Impedance Measurements Andrew F. Seybert University of Kentucky Lexington, KY 40506-0503 859-257-6336 x 80645 [email protected] Applicable Standards. There are two standards1,2 for the measurement of acoustical properties of materials: ASTM E1050 and ISO 10534-2. These two standards parallel one another; the first was developed in the U.S. by ASTM and the second developed by the International Standards Organization. Both describe what has come to be known as the “two-microphone” or “transfer-function” method of measuring absorption and impedance of acoustical materials.3,4 These standards establish acceptable conditions under which reliable data may be obtained; however, good practice suggests that equipment and test conditions exceed the minimal requirements of the standards. The Two-Microphone Method. The two-microphone method is shown schematically in Figure 1 below. A sample of the material to be tested is placed in a sample holder and mounted to one end of a straight tube. A rigid plunger with an adjustable depth is placed behind the sample to provide a reflecting surface. A sound source, typically a high-output acoustic driver, is connected at the opposite end of the tube. A pair of microphones is mounted flush with the inner wall of the tube near the sample end of the tube. Figure 1 The Two-Microphone Method 1 A multi-channel spectrum analyzer is used to obtain the transfer function (frequency- response function) between the microphones. In this measurement, the microphone closer to the source is the reference channel. From the transfer function H12, the pressure reflection coefficient R of the material is determined from the following equation: − jks H12 − e j2k (L+s) R = jks e e − H12 where L is the distance from the sample face to the first microphone and s is the distance between the microphones, k = 2πf/c, f is the frequency, and c is the speed of sound. -
Particle Enrichment in Longitudinal Standing Bulk Acoustic Wave Microfluidics Mingyang Cui Washington University in St Louis
Washington University in St. Louis Washington University Open Scholarship Engineering and Applied Science Theses & McKelvey School of Engineering Dissertations Spring 5-17-2017 Particle Enrichment in Longitudinal Standing Bulk Acoustic Wave Microfluidics Mingyang Cui Washington University in St Louis Follow this and additional works at: https://openscholarship.wustl.edu/eng_etds Part of the Other Mechanical Engineering Commons Recommended Citation Cui, Mingyang, "Particle Enrichment in Longitudinal Standing Bulk Acoustic Wave Microfluidics" (2017). Engineering and Applied Science Theses & Dissertations. 236. https://openscholarship.wustl.edu/eng_etds/236 This Thesis is brought to you for free and open access by the McKelvey School of Engineering at Washington University Open Scholarship. It has been accepted for inclusion in Engineering and Applied Science Theses & Dissertations by an authorized administrator of Washington University Open Scholarship. For more information, please contact [email protected]. WASHINGTON UNIVERSITY IN ST. LOUIS School of Engineering and Applied Science Department of Mechanical Engineering and Materials Science Thesis Examination Committee: J. Mark Meacham, Chair Amit Pathak David Peters Particle Enrichment in Longitudinal Standing Bulk Acoustic Wave Microfluidics by Mingyang Cui A thesis presented to School of Engineering and Applied Science of Washington University in partial fulfillment of the requirements for the degree of Master of Science May 2017 St. Louis, Missouri © 2017, Mingyang Cui Table -
Acoustics the Present and Future Role of Acoustic Metamaterials For
acoustics Review The Present and Future Role of Acoustic Metamaterials for Architectural and Urban Noise Mitigations Sanjay Kumar and Heow Pueh Lee * Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore * Correspondence: [email protected] Received: 25 June 2019; Accepted: 31 July 2019; Published: 1 August 2019 Abstract: Owing to a steep rise in urban population, there has been a continuous growth in construction of buildings, public or private transport like cars, motorbikes, trains, and planes at a global level. Hence, urban noise has become a major issue affecting the health and quality of human life. In the current environmental scenario, architectural acoustics has been directed towards controlling and manipulating sound waves at a desired level. Structural engineers and designers are moving towards green technologies, which may help improve the overall comfort level of residents. A variety of conventional sound absorbing materials are being used to reduce noise, but attenuation of low-frequency noise still remains a challenge. Recently, acoustic metamaterials that enable low-frequency sound manipulation, mitigation, and control have been widely used for architectural acoustics and traffic noise mitigation. This review article provides an overview of the role of acoustic metamaterials for architectural acoustics and road noise mitigation applications. The current challenges and prominent future directions in the field are also highlighted. Keywords: room acoustics; urban noise; low-frequency noise; indoor noise; traffic noise; acoustic metamaterials 1. Introduction Noise is an integral part of the working environment and can be produced almost everywhere viz. rooms, industries, roads, airports, transportations, etc. In this 21st century, due to extreme exploitation of Mother Nature, noise pollution has become a major issue that affects the health and quality of life especially in the city.