The present study investigates the vibration and sound radiation by panels exited by turbulent flow and by random noise. Composite and aluminum panels are analyzed through a developed analytical framework. The main objective of this study is to identify the difference between the vibroacoustic behaviour of these two types of panels. This topic is of particular importance, given the growing interest in applying composite materials for the construction of aircraft structures, in parts where aluminum panels were traditionally being used. An original mathematical framework is presented for the prediction of noise and vibration for composite panels. Results show the effect of panel size, thickness of core, and thickness of face layers on the predictions. Smaller composite panels generally produced lower levels of sound and vibration than longer and wider composite panels. Compared with isotropic panels, the composite panels analyzed generated lower noise levels, although it was observed that noise level was amplified at certain frequencies. 1. Introduction The shift towards composite aircraft fuselage and wing structures and the overall use of new concepts of materials in aircraft manufacturing carry the need of a better understanding of structural and acoustic behaviors associated with these types of materials. The present study provides a novel analytical framework for the prediction of the vibroacoustic behaviour of composite panels. Previous models were developed and validated by the author aiming at the prediction of the vibroacoustic behaviour of flow-excited isotropic panels [1–4]. The present work adds a step forward to the previous models, by advancing the predictive models towards the application and analysis of composite panels’ behaviour. As also shown in previous analysis, the mathematical approach presented has the ability to provide the fast and accurate prediction for various kinds of structural panels, specifically varying panels’ structural properties, panels’ size, thickness, number of layers, and airflow regimes. With the growing interest in composite materials in several fields, the research presented in this study can be useful for a broad range of applications, such as aerospace applications, automotive industry, civil engineering, and high-speed boats, in which the mechanical behaviour of the material should be well understood. This study considers the case of a turbofan aircraft at cruise flight conditions, a situation in which interior noise levels are governed by the transmitted turbulent boundary layer noise into the cabin. It is
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