Date Available


Year of Publication


Document Type





Mechanical Engineering

First Advisor

Tingwen Wu


Perforated tubes in mufflers are generally modeled by the transfer impedance approach since modeling the actual geometry of the perforated tubes with holes is very expensive due to the enormity of the boundary elements required. With the development of the substructuring technique which greatly reduces the number of elements required detailed modeling of the perforated tubes has become possible. In this thesis mufflers with perforated tubes are analyzed by modeling the actual geometry and locations of holes on the perforated tubes. The Direct-mixed-body boundary element method with substructuring is used to model the mufflers. Mufflers of various geometry containing perforated tubes with holes of different sizes and porosity are tested. The results obtained from the analyses are compared with the empirical formula results and experimental results. A preliminary investigation on the detailed modeling of flow-through catalytic converters is also conducted.