Modeling Noise Control Materials

Biot's theory provides a framework for the numerical modeling of propagating stress waves in elastic porous materials. A finite element method technique based on the adaptation of Biot's theory [1, 2] to acoustic porous material that is applicable for the solution of complex systems consisting of porous, fluid and structural media is described. Acoustic indicators such as absorption coefficient and transmission loss are calculated for flat samples and these results are compared to known solutions. Finally the transmission loss of a complex dash system is computed and contrasted with the corresponding planar multi-layer results.