Dynamic equations for fluid-loaded porous plates using approximate boundary conditions

Systematically derived equations for fluid-loaded thin poroelastic layers are presented for time-harmonic conditions. The layer is modeled according to Biot theory for both open and closed pores. Series expansion techniques in the thickness variable are used, resulting in separate symmetric and antisymmetric plate equations. These equations, which are believed to be asymptotically correct, are expressed in terms of approximate boundary conditions and can be truncated to arbitrary order. Analytical and numerical results are presented and compared to the exact three dimensional theory and a flexural plate theory. Numerical comparisons are made for two material configurations and two thicknesses. The results show that the presented theory predicts the plate behavior accurately. (C) 2009 Acoustical Society of America. [DOI: 10.1121/1.3086267]