LAUSR

Abstract The sound transmission loss (STL) of composite barriers is investigated by means of 3D structure-acoustic finite element analysis (FEA). A simplified calculation method for fast assessment of sound insulation properties of complex structures is proposed, simulating standardised laboratory test conditions of reverberation chambers. The numerical and experimental results of STL for an exemplary composite barrier – double sash window with movable pillar – in multiple geometric configurations, are analysed in a typical frequency range between 50 Hz and 5000 Hz in the one-third-octave band. Different types of window’s frame material properties or window’s glazing types are compared. It is found that a very detailed description of the system is needed in order to accurately simulate STL characteristics in the given frequency range. However, if acquiring STL trend curve as in standardized test is sufficient, a significant simplifications in the computational model are acceptable. A satisfactory agreement between the numerical simulations and the standardized test measurement data is obtained in the investigated frequency range. The FEA model confirms the importance of primary structural resonance in determining the STL. The impact of different model parameters on the STL is evaluated.