Study on the sound transmission through circular aperture array with viscous and thermal effect

The aperture array is commonly applied in HVAC (heating, ventilation, and air conditioning) system, micro-perforated panel and acoustic metamaterial. Investigating its acoustic properties is of great significance. The effects of aperture number and distance are estimated for aperture array, though the dimensions affect the sound transmission loss (STL) of apertures significantly as well known. In this paper, the model of the diffuse acoustic field STL of aperture array was proposed to analyze the insulation performance. The interactions among apertures at the inlets and outlets are evaluated by utilizing the coupling radiation impedance. The viscous and thermal boundary layer effect inside apertures have also been incorporated. The accuracy of this model is validated by comparisons with the acoustic finite element method.