A hybrid transfer matrix-statistical energy analysis approach to robust sound transmission modelling

Flat finite-sized built-up systems such as roof panels, double leaf walls,... are nowadays widely used in building construction. In order to optimize the acoustic performance of such systems, a robust prediction tool is required. The framework of the proposed methodology, presented in this work, is based on the hybrid finite element-statistical energy analysis approach, made possible by the diffuse field reciprocity relationship. The wall is then modelled deterministically using finite elements and the rooms as stochastic subsystems. In this work a new hybridization is established between the transfer matrix method and the statistical energy analysis in order to replace the computationally expensive finite element analysis by a much more efficient transfer matrix method. In doing so, two important limitations of the transfer matrix method itself are overcome. First, the finite size is incorporated using a modal based transfer matrix method. Second, the stochastic subsystems allow the computation of the variance, inherent to the diffuse field assumption. Two validation examples are considered, in which the approach is validated against other numerical and experimental data for thick and layered building systems.