Ray-tracing modelling of the diffraction by half-planes and slits based on the energy flow lines concept

Geometrical acoustics models are currently the most popular prediction tools in room-acoustics due to their low computing load. However, they seldom take into account the diffraction occurring at free edges or apertures. Moreover, the existing diffraction models implemented in geometrical acoustics algorithms are either limited to specularly reflected paths or either present excessive complexity. Recently, a diffraction model based on an approximation of the far-field direction of the Poynting's vector has been implemented in an acoustic ray-tracing software. This model can handle both diffuse and specular reflections and sets no limit in terms of order of reflection or diffraction by half-planes. Results for single and double diffraction problems are presented here. Moreover, this model is developed to handle diffraction occurring at slits and comparisons with experimental results are shown.