Acoustic Radiation from Fluid-loaded Stiffened Composite Laminated Plates according to Layerwise Plate Theories

Acoustic radiation from a fluid-loaded laminated composite plate with two sets of periodic stiffeners is investigated, in which the expressions for the stress tensors due to the transverse shear deformation are included on the basis of Reddy’s layerwise plate theories. By employing the Fourier transform method and the stationary phase approximation, far field pressure expressions are presented to address the acoustic characteristics of the stiffened laminated plate. Sound pressure obtained from the layerwise theory are compared with existing results from the classic thin plate theory, and increasingly remarkable differences among them are found from medium to high frequency range. Numerical calculations are subsequently carried out to explore the influences of the spacing of the stiffeners, the thickness of the plate, and the lamination schemes on the sound pressure. Practical concerns are addressed which would be beneficial to the optimization design of stiffened plates.