Experimental validation of a coupled acoustic fluid-poroelastic-plate model with frontal and lateral source excitations

This work deals with a coupled acoustic problem involving a compressible fluid and a poroelastic material contained in a cavity whose walls are all rigid except for the top, where a flexible plate is placed. The fluid is described utilizing its acoustic pressure, whereas, for the plate, the Naghdi model is used. The mechanical behaviour of the absorbing layer attached to the plate is described by using a Biot-Allard model, where the governing equations are written in the displacement-based formulation. A comprehensive three-dimensional analysis is performed, comparing numerical and experimental results and showing the advantages of using the Biot-Allard poroelastic model over other fluid-equivalent formulations, such as the Allard-Champoux model.