Study of the Effect of Microcellular Structures on Sound Absorption of Exhaust Performance Mufflers

Abstract

Microcellular structures were introduced into exhaust performance mufflers for the study of their impact on the sound absorption properties using a numerical simulation approach. Data extracted from the literature were juxtaposed with values obtained from the simulation. The results obtained showed that the introduced structures significantly improved the sound absorption properties of the exhaust performance mufflers. Attenborough's model proved to be the best fit for packed beds of near-spherical structures. It gave a feasible correlation between the data extracted from the literature and those obtained by simulation. These results reinforced the model's effectiveness in predicting the acoustics behaviour of these materials. The Johnson-Champoux-Allard (JCA) model was effective in predicting sound absorption behaviours in metallic microcellular structures. The study revealed that the thickness and structural composition of soundproofing materials can significantly affect the propagation of pressure waves. Engine-generated noise can be eliminated and equipment lifespan lengthened if these findings are implemented.