AUTHORS : Jianghui Xin, Yuanyuan Zhang

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ABSTRACT : Engine noise is mainly from exhaust noise. Without adding muffler, at a certain speed, the noise up to 100 decibels. Reduce engine exhaust noise, and to high-temperature exhaust gas can be safely and effectively. Muffler as part of exhaust pipe, should ensure that the exhaust flow, resistance and sufficient strength. This research takes an exhaust silencer as a study object, and a muffler sound field model is established by using the finite element pre-processing software Hypermesh. According to the finite element analysis of acoustics and fluid, silencer acoustic performances are analyzed and the muffler transmission loss is calculated. Through the improvement of the first cavity, the transmission loss is compared with the original structure. The results clearly reflect muffler sound field conditions, and provide a basis for the muffler's improving and optimal design.

KEYWORDS : Muffler, Exhaust noise, Finite element model, Transmission loss, Acoustic characteristics

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