Abstract
Time-domain sound propagation equations in porous media usually involve convolutions, which can be computationally cumbersome. Indeed, a naïve approach would require to store the acoustic variables at every time-step, which would lead to an unacceptable memory space for long range propagation. To reduce the computational burden associated to convolutions, an efficient numerical method, referred to as the auxiliary differential equation (ADE) method, originated from the computational electromagnetic community and presented in Dragna et al. [J. Acoust. Soc. Am. 138, 1030–1042 (2015)] is proposed. The idea behind is to approximate the relaxation functions, which depend on the porous media properties, by rational functions in the frequency-domain. The time variation of the convolution is thus given by first-order differential equations which can be solved using standard time-marching schemes. The accuracy of the method is investigated and compared to that of recursive convolution methods. The ADE method is then applied for outdoor sound propagation using the time-domain rigid-frame model proposed by Wilson et al. [Appl. Acoust. 68, 173–200 (2007)] in the ground. Results obtained with Wilson's model are compared at long range to those obtained with Zwikker and Kosten's equations and with an equivalent impedance surface for different flow resistivities.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.