Analysis of acoustic properties of multi-layered structures by means of effective acoustic impedance matrix

The effective acoustic impedance matrix (Z(k)) is proposed, and its applications are discussed. After defining (Z(k)), it is shown that (Z(k)) for any kind of multilayered structure can be determined successively from the bottom substrate to the top layer. The use of (Z(k)) obviates some problems often occurring in the numerical calculation of multilayered structures. Using three typical examples, it is shown how (Z(k)) can be conveniently applied to characterize acoustic wave excitation and propagation in certain complicated layered structures as well as in semi-infinite substrates.<
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