A coupled FE-RRM-based numerical model for analysis of energy transmission loss through stiffened double-wall panel due to TBL excitation

Abstract: We propose a fully coupled numerical model to predict energy transmission through a turbulent boundary layer (TBL) excited stiffened double-leaf flexible aircraft panel using a finite element (FE) framework. Mindlin first order shear deformation model is adopted for the panels and a TBL-structure-acoustic coupling model is developed using finite element-radiation resistance matrix (FE-RRM) approach to predict the transmission loss (TL) through double-leaf panels with variable thickness and stiffener orientation. The model is also capable to capture the contribution of orthotropic lamina sequence and frequency-dependent structural damping in predicting the TL. Thus, a new numerical model is proposed that enables the designers with greater flexibility in terms of the number of panel leaves, boundary, and stiffening condition of the aircraft panel-cavity-panel system, made of isotropic or orthotropic laminates.