Final Thesis

Auralization of aircraft noise considering atmospheric and urban sound propagation

Master Thesis of Reich, Lennart

When assessing how aircraft noise is perceived by residents of nearby urban environments, auralization can be an effective tool. For this purpose, it is necessary to consider how propagation paths are impacted by both, the atmosphere and the urban environment. In the atmosphere, the inhomogeneity of the medium plays an important role on sound propagation, whereas in urban environments, the sound paths are mainly determined by reflections and diffractions occurring at the surfaces and edges of buildings. While there are individual methods that are able to consider one of these aspects, the auralization of the combined scenario requires the consideration of both aspects. To address this issue, this work proposes a combined propagation model combining two existing simulation tools, one for atmospheric and the other for urban sound propagation. This so-called virtual source method is able to predict the influence of atmospheric refraction and translation on the different paths occurring in an urban environment. To achieve this, the original source position is adjusted based on the atmospheric free field path between source and receiver. Then, auralization parameters are derived for the paths determined by the virtual source method. Finally, the propagation model is coupled with an existing auralization framework to auralize a simple flyover scenario.