Optimizing the conversion of area and line sources into point source arrays to comply with modeling those sources per ISO 9613-2, Acoustics – Attenuation of sound during propagation outdoors

摘要

ISO 9613-2, Attenuation of sound during propagation outdoors,1 is commonly used in the calculation of sound levels from various types of facilities and industrial plants. The calculation method is based on point source modeling but virtually all facilities consist of point, area and line sources. In regard to area and line sources, as long as the receiver location is greater than twice the major dimension of the source, then it may be modeled as a point source but when the receiver distance is less, then the source shall be converted into an array of point sources. This paper presents the results of analytically modeling variously sized area and line sources employing different array densities and comparing those results to an equivalent point source noting the convergence point. In addition, aspect ratios are examined and normalized to simplify determining point array densities.