Experimental/FE numerical correlation of a composite sandwich panel of a high-speed train

The aim of this work is the correlation between experimental and numerical modal analyses of a composite sandwich panel used for a high speed train in order to verify FE model reliability for the acoustic performances of the investigated sandwich panel, finalized to its acoustic optimization. Firstly, the results of the experimental determination of the Transmission Loss (TL) property of the panel, through the employment of an intensity sound probe, are presented. The obtained TL parameter is useful to characterize the material acoustic attenuation with respect to the design specifications compliance. Secondly, an experimental and a numerical modal analyses are performed. Starting from both FE simulation and impact testing outcomes, it is possible to implement a correlation study through the computation of the Modal Assurance Criterion (MAC). Good agreement between numerical and experimental analyses have been found up to the frequency 1000 Hz. In order to realize a numerical model reliable at higher frequencies, a more careful impact testing procedure has to be carried out. Future developments could regard the possibility to refine FE-Test correlation implementing a sensitivity and updating procedure, so to define an accurate FE model which could be used for the improvement process of the panel acoustic performances.