Patent attributes
An apparatus is disclosed for increasing the residency time of a reducing agent in an exhaust gas cleaning system. The apparatus includes a first double-walled element in communication with a flow of exhaust having a first inner wall and a first outer wall. A second double-walled element is included having a second inner wall and a second outer wall. The second double-walled element is arranged in relation to the first double-walled element such that the second inner wall is positioned between the first inner wall and the first outer wall and the first outer wall is positioned between the second inner wall and the second outer wall. This arrangement defines a plurality of flow paths that reverses the flow of exhaust back on itself and then reverses the flow of exhaust once again.
