An Efficient Method to Calculate Sound Diffraction over Rigid Obstacles
Tuesday 2 june, 2015, 17:20 - 17:40
0.3 Copenhagen (49)
Accurate and efficient calculations of diffraction over rigid obstacles are very useful for sound propagating over city canyons and for situations where fast evaluations are required, such as sound virtual reality or sound effect of video games. Geometrical acoustic theory offers very accurate solutions for sound diffraction over obstacles. However, these solutions depend on very complicate input parameters and usually take more CPU time than engineering approximations. In this paper, a serial simplified diffraction functions to approximate the single, double and multiple diffraction are presented. The formulating of these functions is based on simplification of Fresnel Integral and their accuracies depend on the relative locations among the source, obstacle and receiver. The phase of the sound wave is included in these functions. Compared with the non- simplified diffraction function, most of the receiver positions can reach an acceptable accuracy except the positions close to the boundary line where 3 dB error is expected.
ICS file for iCal / Outlook