Finite element investigations on the vibroacoustic performance of plane plates with random stiffness

The present work deals with the numerical analysis of some configurations of sandwich panels. It illustrates the results of some investigations on how truss-like cores with randomized stiffness can be used to modify the vibroacoustic performances. Finite element models of selected macroconfigurations of a given sandwich panel are analyzed in terms of both mean square structural velocity and radiated acoustic power. All the numerical interrogations were pursued with the proper finite element models meshed to represent the selected frequency range. Previous models and results, obtained with CPU time-consuming optimization approaches, are here re-investigated by analyzing the effect of addition of a random stiffness distribution. The obtained results are encouraging since it seems that the random distribution of the core stiffness can be fruitfully used to reduce and/or to modify the radiated noise from a sandwich structure. The randomness is not introduced here in order to take into account material or geometrical uncertainties as commonly done in the literature, but to enhance the vibroacoustic performance of sandwich panels.