Three-pass mufflers with perforated inlet/outlet tubes

摘要

The one-dimensional (1-D) analytical approach based on transfer matrix method is developed to predict and analyze the acoustic attenuation characteristics of three-pass mufflers with perforated inlet or (and) outlet tube(s) and validated by comparing the transmission loss predictions from the present 1-D analytical approach and experimental measurement for three different muffler configurations. The approach is then used to investigate the effects of perforations of inlet and/or outlet tube(s) and flow on the acoustic attenuation performance of the mufflers. The results indicated that the resonance contributed by the end cavity shifts to higher frequency with the increase of perforation area, and disappears when perforation area reaches a certain value, leading to a remarkable impact on the acoustic attenuation behavior of the mufflers in middle frequency range. The mean flow increases transmission loss of the mufflers at pass frequency and decreases acoustic attenuation in the middle-frequency range in general. (C) 2019 Elsevier Ltd. All rights reserved.