This paper aims to apply the radiative transfer method to acoustical diffraction by obstacles. Some fictitious sources are introduced at diffracting wedges and a transfer equation based on energy balance determines the diffracted powers. It leads to a set of linear equations on diffracted powers which can be solved in a finite number of steps. It is then possible to calculate the diffracted field anywhere. Some applications to diffraction by obstacles of various shapes are presented. Results of this method are compared with Geometrical Theory of Diffraction and BEM reference calculations. It is shown that this method is particularly efficient in case of multiple diffraction where the ray-tracing technique involves an infinite number of rays between a source and a receiver point.

Topics
Noise barriers, Geometrical acoustics, Acoustic signal processing, Acoustic wave diffraction, Radiative transfer, Computer graphics, Functional equations, Diffraction optics, Geometrical optics, Optical absorption
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© 2005 Acoustical Society of America.
2005
Acoustical Society of America
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