Prediction of the Sound Reduction Index: Application to

ABSTRACT: The calculation of the sound reduction index in modal analysis is presented in a general way; different approaches are described. These calculations are done in two steps: a vibratory study to determine the transverse displacement of the plate and a study of radiation. The specificity of orthotropic plates is presented. This study led to programming a calculation algorithm. Initial hypotheses are indicated, as well as results obtained for various plates or partitions. Modal analysis calculation results are then compared to the Cremer-Sewell approach results and to laboratory measurements, in particular for “Monomur ” walls