Sound attenuation in expansion chamber muffler using plane wave method and finite element analysis

Abstract

This paper addresses the acoustical performance of a cylindrical expansion chamber muffler with single inlet, single outlet configuration. Analytical result for the transmission loss for the muffler has been derived by using the plane wave theory and the results are compared with the finite element analysis. The analysis for both the cases is done for the frequency varying from 50 Hz to 1500 Hz. The general peak value for transmission loss for the analyzed geometry was 13.16 dB, however a sharp transmission loss peak was also observed. The critical values for the transmission loss at three different frequencies are studied with the aid of finite element simulation.