Download or read book Vibro Acoustic Sources in Lightweight Buildings written by Andreas Mayr and published by Logos Verlag Berlin GmbH. This book was released on 2010 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work reported in this thesis addresses the problem of structure-borne sound transmission in buildings. Vibrating sources, such as services plant and domestic appliances, transmit vibro-acoustic power, causing noise complaints by occupants in rooms removed from the source room. There is not yet an accepted practical method of predicting the installed power into floors or supporting walls, and thence the resultant sound pressure in rooms. This study concentrates on the prediction of the installed power from mechanical installations in lightweight buildings composed of framed and ribbed plates. To identify the characteristics of such receiver elements, a field survey has been undertaken, which involved measurement of the point and transfer mobilities of common wall and floor structures. It is shown that the range of measured values of receiver point mobility is surprisingly small and that the constructions investigated often displayed thin plate-like characteristics, with relatively small spatial variations in point mobility. These field measurements give support to the notion of averaging over contacts. This single equivalent receiver mobility has been assembled both from measured data and from the approximate method and then used in combination with single equivalent source data, to yield an approximate prediction of the installed power. The agreement obtained between the exact and approximate values allowed consideration of a practical implementation of the approximate prediction method, based on a reception plate method which yields the activity and mobility of the tested machine as single equivalent values.
Download or read book Structure borne Sound Sources in Buildings written by Matthias Lievens and published by Logos Verlag Berlin GmbH. This book was released on 2013 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Structure-borne sound sources are vibrational sources connected in some way to the building structure. The mechanical excitation of the building structure leads to sound radiation. This is an important source of annoyance in modern light-weight buildings. The prediction of the sound pressure level from structure-borne sound sources is highly complicated because of the complexity involved in the coupling between source and receiver structure. The current standard on characterisation of service equipment in buildings EN 12354-5, can deal with sources on heavy structures (high-mobility source) but to date, there is no engineering method available for the case of coupling between source and receiver. A case study of a washing machine on a wooden joist floor is investigated in this thesis. In the first part, measurements in the coupled state are conducted. It is shown that the normal components are sufficient to predict the sound pressure level. However, this only applies to the coupled state. In the second part, a true prediction is calculated from independently measured source and receiver quantities. The difference between predicted and directly measured sound pressure level leads to considerable errors of up to 20 dB at low frequencies. This shows that the normal components are not sufficient to predict the coupling between a washing machine and a wooden floor.
Download or read book Building Acoustics and Vibration written by Osama A B Hassan and published by World Scientific Publishing Company. This book was released on 2009-06-24 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt: As a comprehensive reference dedicated to sound and vibration in buildings, Building Acoustics and Vibration addresses the basic and advanced principles that can be used to solve practical and theoretical problems typically encountered in building and architectural acoustic practices. In addition, physical and mathematical concepts are introduced and developed sufficiently to make this publication a self-contained and up-to-date source of information for readers. Building Acoustics and Vibration is a must-have textbook for engineering students, engineers, and consultants involved in the sound, vibrations and building environment. With comprehensibility and versatility in the presentation of knowledge, this highly anticipated publication will easily fill the gap in the literature of building engineering and sciences, which presently lacks an authoritative guide on the theoretical and practical aspects of building acoustics and vibration.
Download or read book Vibro Acoustics of Lightweight Sandwich Structures written by Tianjian Lu and published by Springer. This book was released on 2014-07-08 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vibro-Acoustics of Lightweight Sandwich Structures introduces the study of the coupled vibration and acoustic behavior of lightweight sandwich structures in response to harmonic force and sound pressure. This book focuses on the theoretical modeling and experimental investigation of lightweight sandwich structures in order to provide a predictive framework for vibro-acoustic characteristics of typical engineering structures. Furthermore, by developing solution tools, it concentrates on the influence of key systematic parameters leading to effective guidance for optimal structure design toward lightweight, high-stiffness and superior sound insulation capability. This book is intended for researchers, scientists, engineers and graduate students in mechanical engineering especially in structural mechanics, mechanics and acoustics. Fengxian Xin and Tianjian Lu both work at the School of Aerospace, Xi’an Jiaotong University.
Download or read book Current Perspectives and New Directions in Mechanics Modelling and Design of Structural Systems written by Alphose Zingoni and published by CRC Press. This book was released on 2022-09-02 with total page 4438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems comprises 330 papers that were presented at the Eighth International Conference on Structural Engineering, Mechanics and Computation (SEMC 2022, Cape Town, South Africa, 5-7 September 2022). The topics featured may be clustered into six broad categories that span the themes of mechanics, modelling and engineering design: (i) mechanics of materials (elasticity, plasticity, porous media, fracture, fatigue, damage, delamination, viscosity, creep, shrinkage, etc); (ii) mechanics of structures (dynamics, vibration, seismic response, soil-structure interaction, fluid-structure interaction, response to blast and impact, response to fire, structural stability, buckling, collapse behaviour); (iii) numerical modelling and experimental testing (numerical methods, simulation techniques, multi-scale modelling, computational modelling, laboratory testing, field testing, experimental measurements); (iv) design in traditional engineering materials (steel, concrete, steel-concrete composite, aluminium, masonry, timber); (v) innovative concepts, sustainable engineering and special structures (nanostructures, adaptive structures, smart structures, composite structures, glass structures, bio-inspired structures, shells, membranes, space structures, lightweight structures, etc); (vi) the engineering process and life-cycle considerations (conceptualisation, planning, analysis, design, optimization, construction, assembly, manufacture, maintenance, monitoring, assessment, repair, strengthening, retrofitting, decommissioning). Two versions of the papers are available: full papers of length 6 pages are included in the e-book, while short papers of length 2 pages, intended to be concise but self-contained summaries of the full papers, are in the printed book. This work will be of interest to civil, structural, mechanical, marine and aerospace engineers, as well as planners and architects.
Download or read book Vibro Acoustics Volume 2 written by Anders Nilsson and published by Springer. This book was released on 2015-09-15 with total page 453 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Vibroacoustics of Lightweight Structures with Embedded Acoustic Black Holes written by Yu Xiong and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Interest in lightweight and quiet structures is growing in the aeronautical, automotive, and marine industries. However, lightweight structures can easily result in mechanical vibration and noise issues from an acoustician's view. Therefore, a demand for a novel structure that can be lightweight and quiet is imperative. An acoustic Black Hole (ABH) effect is one of the possible methods to resolve this conflict. The ABH is a practical, lightweight, passive vibration control technique and has been well developed in recent years. In an effort to begin using the ABH effect to design an ABH structure for real applications in the industry, in chapter three of this thesis, a hybrid vibroacoustic analytical model is developed. It allows the engineers to understand the sensitivity of the acoustical responses of the ABH structure with respect to the design variables of material properties and structure dimensions in an analytical form. The hybrid analytical model is then used for optimizing the vibroacoustic responses of an ABH beam structure to provide design guidelines for minimizing the noise radiated by the ABH beam structure through the selection of optimal material properties and structure dimensions. Improving low frequency performance is essential for real applications of ABH structures. In chapter four, by establishing the correlation between local ABH modes and radiation efficiency, the results show the low frequency performance of ABH plates essentially depends on the first low order ABH modes. Following the design guidelines obtained from the hybrid vibroacoustic analytical model, several plates with embedded multiple ABH cells are studied using a structural-acoustics simulation to evaluate and tailor the vibration response and resulting structural-acoustic radiation by attaching discrete tuning masses at the center position of each ABH cell. An appropriate amount of tuning mass (4.7 g) adjusted the reduction dip of radiation efficiency at the critical frequency (2700Hz), showing that a potential improvement could be achieved to mitigate the coincidence dip in sound transmission problems. Non-uniformly distributed tuning masses enhanced the reduction of the plate sound radiation coupling. An additional 4 dB reduction in one-third octave band radiated sound power was achieved, and a total 8 dB reduction was obtained compared to the uniform plate case. The first local ABH modes were tuned to lower frequencies in order to improve the low frequency vibroacoustic performance of the plate structures. Many noise and control applications demand panel structures with high Transmission loss (TL) and low weight. The ABH plates have the potential to act as promising candidates for TL applications. In chapter five, a new multi-scale ABH plate design with two different ABH sizes is proposed. The multi-scale ABH plate results are compared with the results from a single-scale ABH plate, all with and without damping materials and an undamped uniform plate. The measured TL results showed the damped single-scale ABH plate achieved improved TL performance compared with a uniform plate by increasing the TL 5-7 dB at and above the coincidence dip. The new proposed multi-scale ABH plate flattens the TL curve, nearly eliminating the coincidence dip band without adding a net mass compared to the uniform plate. The multi-scale design increased the TL 3 dB relative to the single-scale design, and a total 10 dB TL increase to the undamped uniform plate. Various weights of tuning masses are attached at the center of the ABH cells to manipulate the ABH cut-on at the desired frequency. The results show that adding a tuning mass of 20 g to each large ABH cell, of the damped multi-scale ABH plate, improved the TL 2 dB in the low-frequency bands. The added tuning mass created a series of local resonant and high loss modes in the low-frequency region. The ABH plates not only perform better on TL, but also have less total mass. The damped multi-scale ABH plate is 7\% lighter than the uniform plate. Although the damping materials and tuning masses were applied, the overall weight advantage is still attained. This is the first insight into embedding two different size ABH cells and applying tuning masses to improve the plate TL characteristics.
Download or read book Active Control of Noise and Vibration written by Colin Hansen and published by CRC Press. This book was released on 2012-11-02 with total page 1564 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrating active control of both sound and vibration, this comprehensive two-volume set combines coverage of fundamental principles with the most recent theoretical and practical developments. The authors explain how to design and implement successful active control systems in practice and detail the pitfalls one must avoid to ensure a reliable and stable system. Extensively revised, updated, and expanded throughout, the second edition reflects the advances that have been made in algorithms, DSP hardware, and applications since the publication of the first edition.
Download or read book Issues in Acoustic and Ultrasound Technology 2013 Edition written by and published by ScholarlyEditions. This book was released on 2013-05-01 with total page 993 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Acoustic and Ultrasound Technology: 2013 Edition is a ScholarlyEditions™ book that delivers timely, authoritative, and comprehensive information about Applied Acoustics. The editors have built Issues in Acoustic and Ultrasound Technology: 2013 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Applied Acoustics in this book to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Acoustic and Ultrasound Technology: 2013 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Advances in Engineering Materials Structures and Systems Innovations Mechanics and Applications written by Alphose Zingoni and published by CRC Press. This book was released on 2019-08-21 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Engineering Materials, Structures and Systems: Innovations, Mechanics and Applications comprises 411 papers that were presented at SEMC 2019, the Seventh International Conference on Structural Engineering, Mechanics and Computation, held in Cape Town, South Africa, from 2 to 4 September 2019. The subject matter reflects the broad scope of SEMC conferences, and covers a wide variety of engineering materials (both traditional and innovative) and many types of structures. The many topics featured in these Proceedings can be classified into six broad categories that deal with: (i) the mechanics of materials and fluids (elasticity, plasticity, flow through porous media, fluid dynamics, fracture, fatigue, damage, delamination, corrosion, bond, creep, shrinkage, etc); (ii) the mechanics of structures and systems (structural dynamics, vibration, seismic response, soil-structure interaction, fluid-structure interaction, response to blast and impact, response to fire, structural stability, buckling, collapse behaviour); (iii) the numerical modelling and experimental testing of materials and structures (numerical methods, simulation techniques, multi-scale modelling, computational modelling, laboratory testing, field testing, experimental measurements); (iv) innovations and special structures (nanostructures, adaptive structures, smart structures, composite structures, bio-inspired structures, shell structures, membranes, space structures, lightweight structures, long-span structures, tall buildings, wind turbines, etc); (v) design in traditional engineering materials (steel, concrete, steel-concrete composite, aluminium, masonry, timber, glass); (vi) the process of structural engineering (conceptualisation, planning, analysis, design, optimization, construction, assembly, manufacture, testing, maintenance, monitoring, assessment, repair, strengthening, retrofitting, decommissioning). The SEMC 2019 Proceedings will be of interest to civil, structural, mechanical, marine and aerospace engineers. Researchers, developers, practitioners and academics in these disciplines will find them useful. Two versions of the papers are available. Short versions, intended to be concise but self-contained summaries of the full papers, are in this printed book. The full versions of the papers are in the e-book.
Download or read book Engineering Acoustics written by Malcolm J. Crocker and published by John Wiley & Sons. This book was released on 2021-01-11 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt: ENGINEERING ACOUSTICS NOISE AND VIBRATION CONTROL A masterful introduction to the theory of acoustics along with methods for the control of noise and vibration In Engineering Acoustics: Noise and Vibration Control, two experts in the field review the fundamentals of acoustics, noise, and vibration. The authors show how this theoretical work can be applied to real-world problems such as the control of noise and vibration in aircraft, automobiles and trucks, machinery, and road and rail vehicles. Engineering Acoustics: Noise and Vibration Control covers a wide range of topics. The sixteen chapters include the following: Human hearing and individual and community response to noise and vibration Noise and vibration instrumentation and measurements Interior and exterior noise of aircraft as well as road and rail vehicles Methods for the control of noise and vibration in industrial equipment and machinery Use of theoretical models in absorptive and reactive muffler and silencer designs Practical applications of finite element, boundary element and statistical energy analysis Sound intensity theory, measurements, and applications Noise and vibration control in buildings How to design air-conditioning systems to minimize noise and vibration Readers, whether students, professional engineers, or community planners, will find numerous worked examples throughout the book, and useful references at the end of each chapter to support supplemental reading on specific topics. There is a detailed index and a glossary of terms in acoustics, noise, and vibration.
Download or read book Sound and Structural Vibration written by Frank J. Fahy and published by Elsevier. This book was released on 2007-01-12 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first edition of Sound and Structural Vibration was written in the early 1980s. Since then, two major developments have taken place in the field of vibroacoustics. Powerful computational methods and procedures for the numerical analysis of structural vibration, acoustical fields and acoustical interactions between fluids and structures have been developed and these are now universally employed by researchers, consultants and industrial organisations. Advances in signal processing systems and algorithms, in transducers, and in structural materials and forms of construction, have facilitated the development of practical means of applying active and adaptive control systems to structures for the purposes of reducing or modifying structural vibration and the associated sound radiation and transmission. In this greatly expanded and extensively revised edition, the authors have retained most of the analytically based material that forms the pedagogical content of the first edition, and have expanded it to present the theoretical foundations of modern numerical analysis. Application of the latter is illustrated by examples that have been chosen to complement the analytical approaches to solving fairly simple problems of sound radiation, transmission and fluid-structural coupling that are presented in the first edition. The number of examples of experimental data that relate to the theoretical content, and illustrate important features of vibroacoustic interaction, has been augmented by the inclusion of a selection from the vast amount of material published during the past twenty five years. The final chapter on the active control of sound and vibration has no precursor in the first edition. * Covers theoretical approaches to modeling and analysis* Highly applicable to challenges in industry and academia* For engineering students to use throughout their career
Download or read book Issues in Acoustic and Ultrasound Technology 2012 Edition written by and published by ScholarlyEditions. This book was released on 2013-01-10 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Acoustic and Ultrasound Technology: 2012 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Ultrasound Technology. The editors have built Issues in Acoustic and Ultrasound Technology: 2012 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Ultrasound Technology in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Acoustic and Ultrasound Technology: 2012 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Audio Engineer s Reference Book written by Michael Talbot-Smith and published by Taylor & Francis. This book was released on 2013-02-01 with total page 674 pages. Available in PDF, EPUB and Kindle. Book excerpt: An authoritative reference on all aspects of audio engineering and technology including basic mathematics and formulae, acoustics and psychoacoustics, microphones, loudspeakers and studio installations. Compiled by an international team of experts, the second edition was updated to keep abreast of fast-moving areas such as digital audio and transmission technology. Much of the material has been revised, updated and expanded to cover the very latest techniques. This is a new paperback version.
Download or read book Vibro Acoustics written by Dhanesh N. Manik and published by CRC Press. This book was released on 2017-04-07 with total page 486 pages. Available in PDF, EPUB and Kindle. Book excerpt: The subject of vibro-acoustics is important for the design of machine elements and structures, to minimize sound generated by them. For better machine designing, it is necessary for machine designers (mechanical engineers) to have a thorough knowledge of vibro-acoustics. Furthermore, since the design cycles of machines have become shorter, designers will have to design quiet machines at the drawing-board stage rather than applying "band-aid" techniques after the machine has been built. Although there is common ground in the treatment of acoustics, the subject of vibration is not very fortunate. Those interested in low-frequency vibration are generally concerned with the modal approach of using natural frequencies and mode shapes, whereas those interested in vibro-acoustics in medium and high frequencies are generally concerned with the wave approach. Since both modal and wave approaches have their advantages, it is a good idea to study both together to get the best out of them. This is useful for a better understanding the physics of vibro-acoustics. Written for students and professionals interested in gaining knowledge, this book systematically integrates the relevant aspects of vibro-acoustics from various viewpoints.
Download or read book Sound Insulation written by Carl Hopkins and published by Routledge. This book was released on 2020-09-23 with total page 650 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sound insulation is an important aspect of building performance. This book is a comprehensive guide to sound and vibration theory and its application to the measurement and prediction of sound insulation in buildings. It enables the reader to tackle a wide range of issues relating to sound insulation during the design and construction stages of a building, and to solve problems in existing buildings. The book has been written for engineers, consultants, building designers, students in acoustics, researchers and those involved in the manufacture and design of building products. Key aspects are that it: * Explains the fundamental theory using examples that show its direct application to buildings * Guides the reader through the links between measurement and theory * Explains concepts that are important for the application, interpretation and understanding of guidance documents, test reports, product data sheets, published papers, regulations and Standards * Makes direct reference to ISO and EN Standards on sound insulation * Contains a large number of illustrations showing measurements, predictions and example calculations for quick reference Carl Hopkins previously worked on building acoustics and environmental noise at the Building Research Establishment. During this time he was involved with sound insulation in research, consultancy, standardization, and building regulations as well as being an advisor on acoustics to government departments. He is currently a Senior Lecturer at the University of Liverpool within the Acoustics Research Unit of the School of Architecture.
Download or read book Advances in Lightweight Materials and Structures written by A. Praveen Kumar and published by Springer Nature. This book was released on 2020-10-13 with total page 827 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents select proceedings of the International Conference on Advanced Lightweight Materials and Structures (ICALMS) 2020, and discusses the triad of processing, structure, and various properties of lightweight materials. It provides a well-balanced insight into materials science and mechanics of both synthetic and natural composites. The book includes topics such as nano composites for lightweight structures, impact and failure of structures, biomechanics and biomedical engineering, nanotechnology and micro-engineering, tool design and manufacture for producing lightweight components, joining techniques for lightweight structures for similar and dissimilar materials, design for manufacturing, reliability and safety, robotics, automation and control, fatigue and fracture mechanics, and friction stir welding in lightweight sandwich structures. The book also discusses latest research in composite materials and their applications in the field of aerospace, construction, wind energy, automotive, electronics and so on. Given the range of topics covered, this book can be a useful resource for beginners, researchers and professionals interested in the wide ranging applications of lightweight structures.