Sound transmission through steel prismatic sandwich panels

Sandwich panels consist of two plates separated by a low-density core, designed to provide high bending stiffness, similar to an I-beam. Advances in manufacturing have enabled the development of various sandwich panels with diverse materials and core configurations, tailored to specific applications. Steel prismatic sandwich panels, two steel plates connected by unidirectional strips via welding, are mainly used in shipbuilding and construction. While the core design can be improved to meet structural and functional requirements, the acoustic performance of these panels, particularly their performance in sound isolation, remains an important consideration. This research investigates the influence of geometry on the sound transmission loss (STL) of sandwich panels with four core configurations: I, V, Y, and X, assuming all are made of steel. Using the finite element method, the coupled structural-acoustic analysis is conducted for sound transmission, showing that V- and X-core panels have superior STL in the stiffness-controlled region and shift first dip, severe dip, to higher frequencies compared to I- and Y-core panels. The differences in STL are linked to variations in shear stiffness, which depend on the deformation mechanisms of the core elements. The V- and X-core panels, featuring inclined core elements, achieve higher stiffness due to the contribution of axial rigidity from the inclined elements in resisting shear loading. Conversely, I- and Y-core panels, with elements perpendicular to the face plates, primarily rely on bending, leading to lower stiffness. These findings highlight the key role of geometry in enhancing the acoustic and structural performance of the steel prismatic sandwich panels.