Excess attenuation for sound propagation over an urban canyon
Journal article, 2010

Because quiet areas in dense urban environments are important to well-being, the prediction of sound propagation to shielded urban areas is an ongoing research focus. Sound levels in shielded areas, such as canyons between rows of buildings, are strongly influenced by distant sources. Therefore, propagation factors such as metrology, screening, and intermediate canyons as occur between a source canyon and a receiver canyon must be addressed in an engineering propagation model. Though current models address many important propagation factors, engineering treatment of a closed urban canyon, subject to multiple internal reflections, remains difficult. A numerical investigation of sound propagation across the open tops of intermediate urban canyons has been performed, using the parabolic equation and equivalent sources methods. Results have been collected for various canyon geometries, and the influences of multiple canyons, canyon/rooftop absorption, variable rooftop height, wind gradient, and correlated versus uncorrelated source models have been investigated. Resulting wideband excess attenuation values ranged from -1 dB to -4 dB per canyon, and were fairly constant with frequency in many useful cases. By characterizing the excess attenuation of canyons intermediate to the source and receiver, the influence of these intermediate canyons could be addressed simply, without the overhead of a detailed numerical calculation. (c) 2010 Elsevier Ltd. All rights reserved.

CITY CANYONS

Urban canyon

Equivalent sources method

Outdoor sound

MODEL

Parabolic equation method

ROAD TRAFFIC NOISE

propagation

Traffic noise

Author

Martin T. Schiff

Chalmers, Civil and Environmental Engineering, Applied Acoustics, Vibroacoustics

Maarten Hornikx

Chalmers, Civil and Environmental Engineering, Applied Acoustics, Vibroacoustics

Jens Forssén

Chalmers, Civil and Environmental Engineering, Applied Acoustics, Vibroacoustics

Applied Acoustics

0003-682X (ISSN)

Vol. 71 6 510-517

Subject Categories

Fluid Mechanics and Acoustics

DOI

10.1016/j.apacoust.2010.01.005

More information

Latest update

11/21/2018