Measurement techniques of the sensitivity functions to characterize the vibroacoustic response of panels under random excitations

This study aims at developing an experimental method for characterizing the vibroacoustic behaviour of panels excited by random pressure fields. Although the method would be theoretically applicable to any stationary and homogeneous random process, diffuse acoustic field (DAF) and turbulent boundary layer (TBL) excitations are considered in this study. The interest of industrials towards these excitations has grown over the years because the associated test means (i.e. coupled chambers or wind tunnel) can hardly be controlled, are subjected to large variabilities between laboratories and are very expensive. The proposed method allows to experimentally characterize a panel under such excitations by separating the contribution of the excitation and the mechanical behavior of the panel. The mathematical formulation of the problem states that the vibroacoustic response of a baffled panel at any point x (belonging to the acoustic domain or located on the panel) can be described by a cross spectral density (CSD) function