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Published on: December 4, 2017
Time-domain modeling of wave-based room acoustics including viscothermal and relaxation effects in air
Brian Hamilton1, Stefan Bilbao1
1Acoustics and Audio Group, University of Edinburgh, 12 Nicolson Square, Edinburgh EH8 9DF, United Kingdom bhamilton.ac@gmail.com, sbilbao@ed.ac.uk.
Abstract:
Air absorption can be a significant source of attenuation, which should be considered in long-duration wideband acoustics simulations. In this short contribution, a time-domain model for three-dimensional wave propagation including viscothermal and relaxation effects (air absorption) is developed and coupled with locally reactive impedance wall conditions through a conservative energy framework. The model is discretised with a finite-difference time-domain method, and numerical stability is established with a discrete energy balance. Numerical examples are presented to demonstrate the proposed method.
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