Efficient finite-difference room acoustics simulation incorporating extended-reacting elements

Jan Wouter Smits
DAFx-2023 - Copenhagen
A method is proposed that allows finite-difference (FD) simulation of room acoustics to incorporate extended-reacting porous elements without adding major computational cost. The porous elements are described by a rigid-frame equivalent fluid model and are incorporated into the time-domain formulation through auxiliary differential equations. By using a local staggered grid scheme for the boundaries of the porous elements, the method allows an efficient second-order scalar approach to be used for the uniform air and porous element interior regions that make up the majority of the computational domain. Both the scalar and staggered schemes are based on a face-centered cubic grid to minimize numerical dispersion. A software implementation running on GPU shows the accuracy of the method compared to a theoretical reference, and demonstrates the method’s computational efficiency through a benchmark example.