Description:
There is a wide range of published literature covering ducts of infinite or semi-infinite length and to a lesser extent there are studies on apertures having restricted dimensions. The work presented in this paper is taken from recent research into the characterization of acoustic devices in finite-length apertures, which may need to allow for a flow of fluid. Results of a finite-element solution for a short duct between two half spaces are presented, along with a closed-form solution [K. H. Jun and H. J. Eom, J. Acoust. Soc. Am. 98, 2324–2327 (1995)] as a validation of the finite-element method. Further results of more complicated aperture geometry, which are not easily amenable to such forms of solution, have also been investigated and are presented.