Models for acoustic sources in urban areas

Abstract

Due to the large increase of populations in urban areas and the impact of sound phenomena on their life, the control of noise in cities is now of great importance. To predict acoustic fields for various urban situations, several theoretical approaches are currently under development. One of these is based on the diffusion theory [J. Picaut et al., Acust. Acta Acust. 83(4), 614–621 (1997)]. Whatever the model used, good predictions will be obtained only if the acoustic sources are accurately modeled. Those sources, classified following a qualitative approach, can be issued from traffic (cars, trucks, buses, motorcycles, etc.) but can also have human components (children in a school-yard, people in a market place, on a pedestrian street,...). The aim of this research concerns the modeling of each kind of source. The main parameters retained are the height, the directivity pattern, the sound power frequency spectrum, and the time history. The modeling techniques are based on statistical analysis and inverse fitting procedures on experimental data carried out over a large sample inside each source category. Afterwards, source characteristics will be introduced in the diffusion model and results will be compared with experiments performed on scale models and real urban situations.