Interior Noise Prediction Methodology

Interior Noise Prediction Methodology

Author: National Aeronautics and Space Administration (NASA)

Publisher: Createspace Independent Publishing Platform

Published: 2018-07-05

Total Pages: 50

ISBN-13: 9781722316792

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The Acoustical Theory for Design of Aircraft Cabins (ATDAC) is a computer program developed to predict interior noise levels inside aircraft and to evaluate the effects of different aircraft configurations on the aircraft acoustical environment. The primary motivation for development of this program is the special interior noise problems associated with advanced turboprop (ATP) aircraft where there is a tonal, low frequency noise problem. Prediction of interior noise levels requires knowledge of the energy sources, the transmission paths, and the relationship between the energy variable and the sound pressure level. The energy sources include engine noise, both airborne and structure-borne; turbulent boundary layer noise; and interior noise sources such as air conditioner noise and auxiliary power unit noise. Since propeller and engine noise prediction programs are widely available, they are not included in ATDAC. Airborne engine noise from any prediction or measurement may be input to this program. This report describes the theory and equations implemented in the ATDAC program. Mathur, Gopal P. and Gardner, Bryce K. Unspecified Center NAS1-18037; RTOP 535-03-11-03...


Noise and Vibration Mitigation for Rail Transportation Systems

Noise and Vibration Mitigation for Rail Transportation Systems

Author: Geert Degrande

Publisher: Springer Nature

Published: 2021-04-08

Total Pages: 719

ISBN-13: 3030702898

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This book reports on the 13th International Workshop on Railway Noise (IWRN13), held on September 16-20, 2019, in Ghent, Belgium. It gathers original peer-reviewed papers describing the latest developments in railway noise and vibration, as well as state-of-the-art reviews written by authoritative experts in the field. The different papers cover a broad range of railway noise and vibration topics, such as rolling noise, wheel squeal, noise perception, prediction methods, measurements and monitoring, and vehicle interior noise. Further topics include rail roughness, rail corrugation and grinding, high-speed rail and aerodynamic noise, structure-borne noise, ground-borne noise and vibration, and resilient track forms. Policy, criteria and regulation are also discussed. Offering extensive and timely information to both scientists and engineers, this book will help them in their daily efforts to identify, understand and solve problems related to railway noise and vibration, and to achieve the ultimate goal of reducing the environmental impact of railway systems.