Experimental investigation of the accuracy of a vibroacoustic model for sandwich-composite panels

Abstract

This paper presents a detailed experimental validation of a general laminate model to predict the vibroacoustic behavior of flat sandwich-composite panels. The accuracy of the model is investigated using a thin and a thick sandwich panel over a large frequency band. Several indicators are compared including the structural wavenumber, modal density, damping loss factor, radiation efficiency, and sound transmission loss. The accuracy of a simpler model based on identifying effective properties of an equivalent orthotropic panel from the General Laminate Model is also discussed. Results show that the vibroacoustic behaviors of flat sandwich-composite panels are accurately estimated using the used model and compare well to the equivalent panel model (for total transmission loss). This experimental investigation is generic and can be used as a benchmark to validate other sandwich models.

Comparative Study of Sound Transmission Losses of Sandwich Composite Double Panel Walls

“…In addition, it was observed that altering the mechanical properties of the plates or their structural size will shift and depress their resonance frequency; and when the modulus was also altered, a depression in the extreme values were noticed. An experimental investigation of the vibro-acoustic response of flat, thin and thick sandwich composite panels was performed by Cherif and Atalla [74]. The general laminate model and the equivalent orthotropic panel model were used to predict the STL of the structures.…”

Modal density and mode counts of sandwich panels in thermal environments

“…Guillaumie [10] studied the modal density of honeycomb sandwich panels with composite faces based on the formula derived by Clarkson [2] and Renji [5]. Cherif and Atalla [11] investigated the modal density of sandwich composite panels http experimentally. Results indicated that combining the input mobility method at low frequency and the wavenumber method at mid and high frequency could obtain better results.…”

Damping loss factor estimation of two-dimensional orthotropic structures from a displacement field measurement

“…A recent article by Cherif and Atalla [24] discusses in detail the measurement vs predictions of different vibroacoustic indicators of two composite sandwich panels (wavenumbers, radiation efficiency, modal density, damping loss and transmission loss). In particular, the use of the wavenumber measurement to estimate the modal density and the radiation efficiency is discussed.…”