Yeon June Kang

In this paper the development of a two-dimensional elastic-absorption finite element model of isotropic elastic porous noise control materials is described. A method for coupling elastic-absorption finite elements with conventional acoustic finite elements is also presented for the cases when the interface between the adjacent air space and the foam is either unfaced or sealed by a membrane. The accuracy of the acoustic/elastic-absorption model has been verified by comparing its predictions with

In this paper, methods for coupling both elastic porous material (i.e., foam) and structural finite elements with either modal or finite element representations of acoustical system are presented. In addition, interface conditions are described for coupling elastic porous material finite elements with acoustical and structural finite elements in various configurations. The foam finite element is based on the elastic porous material theory of Biot. By considering sound transmission through layere

Recently a finite element implementation of Biot’s elastic porous material theory has been developed for the purpose of modeling and optimizing foam noise control treatments [Y. J. Kang and J. S. Bolton, J. Acoust. Soc. Am. 98, 635–643 (1995)]. That finite element formulation was used in the work reported here to study normal incidence sound transmission through a foam wedge placed in a hard-walled duct. It was found that in some frequency bands the transmission loss of the wedge was significant

A finite element model for elastic porous materials is presented that allows for interfaces with adjacent acoustical media that are arbitrarily oriented with respect to the global coordinate system. The foam finite element is based on a complete elastic porous material theory that can account for all the three wave types known to be significant in foams. Example problems are used to illustrate the application of foam finite elements to the optimal design of a foam wedge terminating a waveguide.