Acoustic Treatment Design Scaling Methods. Volume 1; Overview, Results, and Recommendations
Acoustic Treatment Design Scaling Methods. Volume 1; Overview, Results, and Recommendations

Author: National Aeronautics and Space Administration (NASA)

Publisher: Createspace Independent Publishing Platform

Published: 2018-06-15

Total Pages: 40

ISBN-13: 9781721182558

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Scale model fan rigs that simulate new generation ultra-high-bypass engines at about 1/5-scale are achieving increased importance as development vehicles for the design of low-noise aircraft engines. Testing at small scale allows the tests to be performed in existing anechoic wind tunnels, which provides an accurate simulation of the important effects of aircraft forward motion on the noise generation. The ability to design, build, and test miniaturized acoustic treatment panels on scale model fan rigs representative of the fullscale engine provides not only a cost-savings, but an opportunity to optimize the treatment by allowing tests of different designs. The primary objective of this study was to develop methods that will allow scale model fan rigs to be successfully used as acoustic treatment design tools. The study focuses on finding methods to extend the upper limit of the frequency range of impedance prediction models and acoustic impedance measurement methods for subscale treatment liner designs, and confirm the predictions by correlation with measured data. This phase of the program had as a goal doubling the upper limit of impedance measurement from 6 kHz to 12 kHz. The program utilizes combined analytical and experimental methods to achieve the objectives. Kraft, R. E. and Yu, J. Glenn Research Center; Langley Research Center NASA/CR-1999-209120/VOL1, NAS 1.26:209120/VOL1

Aeronautical Engineering
Aeronautical Engineering

Author:

Publisher:

Published: 1971

Total Pages: 580

ISBN-13:

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A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA)

Architectural Acoustics
Architectural Acoustics

Author: Marshall Long

Publisher: Academic Press

Published: 2014-02-05

Total Pages: 985

ISBN-13: 0123982650

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Architectural Acoustics, Second Edition presents a thorough technical overview of the discipline, from basic concepts to specific design advice. Beginning with a brief history, it reviews the fundamentals of acoustics, human perception and reaction to sound, acoustic noise measurements, noise metrics, and environmental noise characterization. In-depth treatment is given to the theoretical principles and practical applications of wave acoustics, sound transmission, vibration and vibration isolation, and noise transmission in floors and mechanical systems. Chapters on specific design problems demonstrate how to apply the theory, including treatment of multifamily dwellings, office buildings, rooms for speech, rooms for music, multipurpose rooms, auditoriums, sanctuaries, studios, listening rooms, and the design of sound reinforcement systems. Detailed figures illustrate the practical applications of acoustic principles, showing how to implement design ideas in actual structures. This compendium of theoretical and practical design information brings the relevant concepts, equations, techniques, and specific design problems together in one place, including both fundamentals and more advanced material. Practicing engineers will find it an invaluable reference for their daily work, while advanced students will appreciate its rigorous treatment of the basic building blocks of acoustical theory. - Considered the most complete resource in the field – includes basic fundamental relations, derived from first principles, and examples needed to solve real engineering problems. - Provides a well-organized text for students first approaching the subject as well as a reliable reference for experienced practitioners looking to refresh their technical knowledge base. - New content for developing professionals includes case studies and coverage of specific focus areas such as audio visual design, theaters, and concert halls.