Prediction of sound absorption coefficients of acoustic wedges using finite-difference time-domain analysis

In this study, a method was developed for predicting sound absorption coefficients of two acoustic wedges by using the finite-difference time domain (FDTD) analysis. The absorption coefficients of two acoustic wedges made of high-density sponge were measured in a low frequency impedance tube. The two wedges were simulated by using the equivalent fluid model based finite-difference time-domain algorithm (EF-FDTD algorithm) in a two-dimensional sound field. The method for predicting absorption coefficients was illustrated, and the factors affecting absorption coefficients were discussed. The calculated sound absorption coefficients were very close to the measured values. The results suggest that the EF-FDTD method is effective and can be potentially used for predicting the absorption coefficient of a wide range of acoustic materials. (C) 2019 Elsevier Ltd. All rights reserved.