Sound-insulation layer modelling in car computational vibroacoustics in the medium-frequency range

International audienceIn a previous article, a simplified low- and medium-frequency model for uncertain automotive sound-insulation layers was developed and experimentally identified and validated. This model is based on a stochastic elastoacoustic element whose mean part comes from an extension of the fuzzy structures theory and depends on three physical parameters: the modal density, the damping rate and the participating mass. A non-parametric probabilistic approach is used to build the uncertainty-accounting stochastic simplified model. This model takes into account the modelling and system-parameters uncertainties and depends on three dispersion parameters. In this paper, the insulation simplified model is implemented in an industrial stochastic vibroacoustic model of a car. An experimental database of tests on vehicles has been carried out and is compared with the predictions. The analysis of these results shows the relevance of the proposed methodology for complex vibroacoustics industrial computational models