Similitudes for the Structural Response and Radiated Power from Plates

This communication investigates exact and distorted similitudes and the related scaling laws for the analysis of both dynamic response and radiated power of rectangular plates. The response of a given panel in similitude from another one is determined from a generalization of the modal approach, allowing the use of mode shapes, natural frequencies and finally radiation functions in order to establish appropriate scaling laws. Analytical models of simply supported rectangular plates are first used to produce both original, replica and distorted model responses under point mechanical excitation. Laboratory experiments are then performed on two baffled simply-supported aluminium panels, a reference and an avatar (a parent panel in distorted similitude) under shaker excitation. All obtained results show that structural response or radiated power of a given plate can be both recovered with satisfactory accuracy by using the related scaling laws, even if distorted models are used. Interestingly, the radiated power can be nevertheless quite well estimated even if the local structural response is not perfectly reconstructed. Even preliminary, these investigations show good potentialities for the estimation of radiation properties of panels using similitude concepts.