Energetics of In-plane Motions in Coupled Plate Structures

Energy flow analysis (EFA) has been used to predict the frequency-averaged vibrational responses of built-up structures at high frequencies. In this study, the frequency-averaged exact energetics of the in-plane motions of the plate were derived for the first time by solving coupled partial differential equations. To verify the EFA for the in-plane waves of the plate, numerical analyses were performed on various coupled plate structures. The prediction results of the EFA for coupled plate structures were shown to be accurate approximations of the frequency-averaged exact energetics, which were obtained from classical displacement solutions. The accuracy of the results predicted via the EFA increased with an increase in the modal density, regardless of various structural parameters. Therefore, EFA is an effective technique for predicting the frequency-averaged vibrational responses of built-up structures in the high frequency range.