Vibro-acoustic design optimisation of a composite sandwich panel using a new experimental setup

Lightweight structures represent an appealing solution in a large number of very different technology areas and they are therefore implemented in a wide range of applications. The high stiffness over weight ratio, typical of lightweight sandwich structures, can however give rise to a poor overall NVH behaviour. Hence, the designer has to ensure that the advantages of a significant weight saving are not nullified by a collateral and undesired reduction of functional vibro-acoustics performance. The present deals with the testing and design optimisation of a composite sandwich panel. NVH performance is evaluated using a dedicated experimental setup for the vibro-acoustic characterisation of lightweight panels. Experimental modal analysis and acoustic insertion loss tests are carried out in order to verify the structural and acoustic numerical models. The predicted improvements in NVH behaviour are experimentally verified with good accuracy. The vibro-acoustic test rig is shown to be a valuable support for the design of composite structures when NVH performance is a key indicator attribute.