Abstract: A muffler for an internal combustion engine includes a cylindrical casing having end plates closing the interior thereof. At least one baffle extending perpendicularly to the central axis of the casing is provided for dividing the interior of the casing into a front chamber and a tuning chamber. A tuning tube extending through the baffle places the front chamber into flow communication with the tuning chamber, and at least one exhaust gas inlet pipe extends into the front chamber through one of the end plates in coaxial relationship with the tuning tube. At least one exhaust gas outlet pipe is provided through the one end plate in parallel relationship with the inlet pipe. Furthermore, one or more openings are provided in the baffle in coaxial relation to the exhaust gas outlet pipe.

Abstract: A gas turbine engine exhaust duct of combination circular and rectangular configuration, and accompanying muffler which provides cooling and silencing of exhaust flow from the gas turbine engine. The arrangement utilizes minimum space without sacrifice of performance.

Abstract: An exhaust gas silencer having a casing including gas inlet and exhaust passages, a plurality of baffle plates having inner portions together defining a central chamber constituting one of said passages and extending longitudinally of the casing, and outer portions extending between the central chamber and the inner wall of the casing to direct the exhaust gas along a tortuous path, each outer portion meeting said inner wall along a line circumferentially spaced from any radius extending from the longitudinal axis of the central chamber through the juncture of the inner and outer portions.

Abstract: A noise suppressor for reducing noise resulting from venting of large volumes of high pressure gas. A first pipe member has an open first end, adapted for attachment to a high pressure gas outlet, and a closed second end. A plurality of second pipe members are attached to the first pipe member sidewall and communicate through openings in that sidewall with the interior of the first pipe member. Within the second pipe members a number of plates are positioned, each having several parallel elongated slots therethrough. The plates within each second pipe member are slanted, with the direction of slant alternating between consecutive plates. Preferably, the consecutive plates are rotated 90.degree. and the elongated slots are slanted with respect to the plate surfaces. A further plate member is provided normal to the second pipe member longitudinal axis. The noise suppressor can be coupled to the high pressure gas outlet by valves or directly.