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Acoustical simulation of a multi-chamber gun muffler internally inserted with extended tube and perforated tube using the FEM

Abstract Because the exploration noise emitted from a gun shooting is huge, it will be harmful for the user’s hearing health, so the noise abatement of the gun’s shooting noise becomes essential. In order to efficiently depress the gun ‘s shooting noise, a multi-chamber muffler internally inserted with three kinds of acoustical reactive elements (orifice, perforated straight tube, and perforated/non-perforated extended tube) is then proposed. To estimate the gun noise, COMSOL, a multiple physical quantities coupled numerical analysis software, is adopted in the acoustical analysis. Consequently, results reveal that the acoustical performance of the muffler hybridized with extended tube will be superior to that of hybridized with the orifice. The porosity of the perforated straight tube will influence the acoustical performance of a muffler. And, the acoustical performance will decrease if the porosity of the perforated extended tube increase.