Sound transmission of an obliquely incident plane wave through an unbaffled plate

This study investigates the sound transmission characteristics of an unbaffled simply supported plate excited by a plane wave incident at an arbitrary angle. The pressure jump across the unbaffled plate results from the combined effects of pure diffraction and pure radiation. In pure diffraction, the plane wave interacts with a rigid unbaffled plate, while in pure radiation, the pressure jump arises from the flexural vibrations of the plate. The pressure at any point in the surrounding fluid medium is expressed as a surface integral involving the product of the pressure jump and the gradient of the free-space Green's function. The Green's function in the two-dimensional wavenumber domain, along with the Euler equation, leads to linear systems of equations for the pressure jump functions. The total incident power includes contributions from the cross-interactions between the incident and scattered fields. The improper double integral in the expression for the transmitted pressure is evaluated using the stationary phase method and the transmitted power is then calculated numerically using this pressure field. Finally, the sound transmission loss is computed and compared with that of baffled and infinite-sized plates. A comparison of incident power and transmitted power between baffled and unbaffled plates is also presented.