An Efficient and Accurate Sound Insulation Prediction Model for Finite Double-Leaf Walls with a Common Studded Frame

Double-leaf walls may achieve a high sound insulation with a relatively low weight. An accurate prediction of the airborne sound insulation of such walls at a reasonable computation cost is challenging, especially when the wall leafs are connected to a common flexible frame. In the present work, a dedicated model is presented for tackling this challenge. In order to keep the computational cost as low as possible, the wall leafs and the cavity are modeled analytically. The frame studs are usually thin-walled metal studs with an open cross section. Accounting for their cross sectional deformation is therefore important, and they are modeled with finite elements. The sending and the receiving rooms are assumed to carry a diffuse sound field, and their coupling to the wall leafs is achieved by invoking the diffuse field reciprocity relationship. With the resulting transmission suite model, the airborne sound insulation is predicted for a range of double-leaf plasterboard walls with single, double and triple plating, with different cavity depths and with and without cavity absorption. The predictions confirm the computational efficiency. Furthermore, they are all validated against experimental results, and in all cases a very good agreement is observed.