Study of the Acoustic Efficiency of Mufflers

The article presents a study of the intake muffler for the Roots blower. Until recently, the design of the mufflers was selected either empirically or through analytical calculations of simplified constructions. In this study we propose an approach based on the finite element modelling, which allows assessing more complex muffler constructions. A three-chamber muffler with several variations of its design was considered. The sequence of calculations and results analysis was determined. For the evaluation of the acoustic efficiency of the mufflers, transmission losses were used. Mufflers with various designs of connecting pipes and sound-absorbing material were considered. As the result of the study, the authors obtained the data showing a change in the acoustic efficiency when the design of the muffler elements was changed, the most efficient use of the sound-absorbing material in the construction, and the influence of the relative position of the elements on the overall noise reduction. Thus, using the Roots blower muffler as a research example, the authors calculated and selected a muffler design that ensured efficient noise reduction in a wide frequency range. 

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