Duct type silencer

Each of the present invention relates to a duct-type silencer, up, down, left, connecting the foam aluminum panel to each of the first fastening port forming the right side wall and to form a duct-shaped sound-absorbing tunnel, it is foamed aluminum panel inside the sound-absorbing tunnel claim connection port 2 fastening and by forming a plurality of columns are arranged to form a sound absorption path, and also the sound-absorbing performance forms a sound-absorbing tunnel with an excellent foamed aluminum panels as well as numerous open the absorption passage be bent in a zigzag form therein in a zigzag shape , while the contact area between the air stream noise as large as possible, and to reduce the flow resistance of the fluid enables to reduce the air flow noise more effectively. Muffler, sound-absorbing material, foam aluminum panel