Boundary Element Analysis of Muffler Transmission Loss with LS-DYNA

This paper presents a case study of applying the boundary element method (BEM) in LS-DYNA for calculating transmission loss (TL) of mufflers. Both the three-point method and the four-pole transfer matrix method are used for calculating the transmission loss. The three-point method is easier to use, but it solves for the transmission loss only and nothing else. The four-pole method has the advantage of providing transfer matrix of the muffler, which contains important parameters when the muffler is connected to another muffler or other components in the silence system. Numerical predictions are examined by experimental results and theoretical results for all test cases. The results show that LS-DYNA can be used to perform muffler transmission loss analysis effectively.