Sound transmission loss of rectangular and slit-shaped apertures: Experimental results and correlation with a modal model

Among noise control techniques, enclosures are widely used. It is known that enclosure acoustic efficiency is strongly influenced by the presence of openings or leaks. Modeling of diffuse field sound transmission loss (TL) of apertures and slits is therefore critical when the enclosure acoustic performance characteristics need to be predicted with confidence either for design or for modifying existing enclosures. Recently, a general model for diffuse field sound TL of rectangular and circular apertures has been developed and validated with respect to existing analytical or numerical models. This paper presents an experimental validation of this new model. The aim was to develop a simple, reliable tool for predicting enclosure insertion loss using statistical energy analysis. Twelve out of the 15 test configurations were found to be reliable and were compared with theoretical models, which in fact correlate closely (without adjustment) with the experimental work.