Vibro-acoustic response and sound transmission loss of sandwich plates with tunable Poisson's ratio core in a hygrothermal environment

In this study, vibro-acoustic response and sound transmission loss of sandwich plates with tunable Poisson's ratio (TPR) core in a hygrothermal environment are investigated. The sandwich plate is taken as a moderately thick plate and various plate theories are used to examine the vibroacoustic behavior. First, the equations of motion of a sandwich plate in the hygrothermal environment are derived based on Hamilton's principle. Then, the solution to free vibration for a simply supported sandwich plate is presented. Next, we obtain the sound power level (SPL) for the point harmonic force exerted on the surface of the sandwich plate using the Rayleigh integral and the sound transmission loss (STL) as the harmonic sound wave is incident on the plate surface. Finally, numerical examples are conducted and discussed. The effects of the core-to-thickness ratio, plate theories, parameters of the TPR core, hygrothermal environment, and incident elevation angle on the SPL and STL of the sandwich plate are analyzed. This study will contribute to the design and manufacturing of lightweight structures in the aviation industry.