Etude vibroacoustique et perceptive du bruit rayonné à l'intérieur d'une voiture de Train à Grande Vitesse

摘要

The vibroacoustical modeling of a TGV may be simplified by analysing the relationships between the mechanical parameters of a structure, the acoustical parameters of radiated signals and the perception of a passenger. This analysis indicates which structural elements induce the percieved sound. The study of these relationships is carried out in parallel on a TGV coach and on a system composed of a vibrating plate closing a cavity. The point in studying this simpler structure is to test and to validate methods of vibration analysis, acoustic and perceptual analysis. The whole study thus comprises two parts for each of the two structures: vibroacoustical modeling and perceptual testing. The vibroacoustical behaviour of the plate/cavity system is described with a analytical modal method. Experiments carried out inside an experimental set up and comparisons with finite-element computations validated this method. Perceptual tests on synthesized and recorded signals highlight, among other factors , the influence on perception of the type of plate and the damping of the cavity walls. The vibroacoustical behaviour of the TGV is described with an experimental modal analysis with no a priori knowledge of exciting sources (LSCE, AR and SSI methods). These methods also allow the synthesis of sound signals from the identified modal parameters. The perceptual tests done with recorded signals allow to characterise the perceptual difference between several architectures of train coaches, several positions inside the coach and several speeds of the whole train.