Evaluation of dissipative silencers efficiency in terms of its sound transmission loss.

Key Fonseca de Lima¹; Victor Pimentel Rosa¹; Nilson Barbieri¹; Renato Barbieri²; Fernando Jun Hattori Terashima¹

¹ PUCPR; ² UDESC

doi:10.20906/CPS/COB-2015-1901

Resumo

The absorbent materials are fibrous and they have the purpose to increase the efficiency of silencers. There are many works that involve purely reactive silencers without absorbent material. However, there are few studies that depict the acoustic behavior of silencers with absorbent material. The difficulty in studying this type of silencers is to characterize the acoustic properties of the absorbent material. The properties required for the evaluation of dissipative silencers are the acoustic characteristic impedance and the complex wave number of the traveling wave. This paper evaluates dissipative silencers through the Finite Element Method (FEM) in terms of its sound transmission loss. The absorbent material is characterized with an inverse methodology.

Palavras-chave: Dissipative Silencers; Absorbent Material; Transmission Loss; FEM