On the prediction of sound diffusion coefficient

Abstract

Acoustic diffusers are one of the key elements in architectural acoustic design. The shape, placement and combination with absorbers along with the physical characteristics of the room such as the volume, size, and geometry make a complex design scenario full of variables and dependencies. The Prediction of scattered reflections with the help of computer modeling is one of the most recent areas of research. Currently the only software package that exist for the simulation of the scattered sound is Reflex [1] from AFMG which can predict scattering and diffusion coefficients of 1D acoustics diffusers using their cross sections. It employs Boundary Element Methods for the calculation purposes. This study intends to develop a sound diffusion prediction software that simulates the measurement laboratory environment of the diffusion coefficients in accordance with 17497-2 ISO standards to predict diffusion coefficients of different type of 2D and 3D acoustics diffusers such as Schroeder, fractal and volumetric diffusers. For the calculations, wave-based room acoustics modeling techniques such as FDTD and BEM will be used. There are plenty of partial differential solvers available that are used for acoustics purposes which will be used in this paper as well. [1] http://reflex.afmg.eu/