An exhaust muffler structure to which an exhaust pipe for guiding exhaust gas from an engine to an exhaust muffler is connected, the exhaust muffler structure comprising a catalyst device, included inside the exhaust muffler structure, having a catalyst for purifying the exhaust gas of the engine, wherein the catalyst device has one end connected to the exhaust pipe and is supported inside the exhaust muffler via the exhaust pipe, and a body portion of the catalyst device is supported by a first partition wall having an inner partition wall and an outer partition wall that is on the outer side of the inner partition wall, and the outer partition wall is fixed to the inner wall of the exhaust muffler, and the inner partition wall is fixed to the outer wall of the catalyst device.

A muffler for an exhaust gas system of an internal combustion engine. The muffler has a muffler housing having at least two interconnected housing shells delimiting a muffler interior. Each housing shell has a connecting edge extending away from the muffler interior. The housing shells are mutually connected by material bonding in the region of their mutually adjacent housing shell connecting edges. An insulating arrangement covers at least regions of the inner side of one of the housing shells. The insulating arrangement has an insulating shell with an insulating shell connecting edge extending away from the muffler interior and the insulating shell is arranged with the insulating shell connecting edge between the mutually adjacent connecting edges of the housing shells and is connected by material bonding to the connecting edges of the housing shells in the region of the insulating shell connecting edge.

A noise abatement system for internal combustion engines comprising: a containment body (12) equipped with an inlet hole (6) for the entry of exhaust gases from an internal combustion engine, a plurality of expansion chambers (10) placed in sequence and separated by parallel dividing partitions (13), each equipped with a through-hole (4) for the passage of gases placing in fluid communication two neighboring expansion chambers (10); said expansion chambers (10) having two opposing through-holes (4), one as gas inlet and one as gas outlet. A rotating shaft (9) is integrated in a rotating turbine (1), along an axis comprising the center of gravity of the expansion chambers (10) up to an opposite end of the containment body (12), said rotating shaft (9) having placed around said axis and on said shaft (9) rotary fins (3) which open and close the through-holes (4) between expansion chambers (10) alternately and generating a swirling movement of the flow of gas entering each expansion chamber (10).

A muffler for a vehicle includes: a muffler shell; a baffle disposed within the muffler shell, and having a first opening and a second opening which allow an exhaust gas to pass therethrough; and a variable valve mounted on the baffle. In particular, the variable valve includes: a valve plate rotatably mounted to open and close the first opening of the baffle; a valve arm connected to the valve plate; and a valve actuator to move the valve arm by variations in pressure of the exhaust gas. The valve plate is capable of rotating in a plane parallel to a plane of the baffle.

A muffler assembly for an exhaust system is in fluid communication with a collector via an exhaust conduit. The muffler assembly includes a primary pipe, a valve, a secondary pipe, a tuner tube and a bleed port. The primary pipe extends through an enclosed volume of the muffler. The valve is operable to restrict flow through the primary pipe. When a standing wave is present, a resonance length is defined by a length of the exhaust system that extends from the collector to the valve. The tuner tube includes an open tuner tube end in fluid communication with the primary pipe and a closed tuner tube end. The tuner tube has a tuner tube length that is substantially one-quarter of the resonance length. The bleed port is formed in the primary pipe, allowing fluid communication with the enclosed volume, and positioned downstream from open tuner tube end.

Disclosed herein is a method and an insert device for an internal combustion engine including: a central exhaust passage; a first expansion chamber in an upstream portion of the exhaust system and in fluidic communication with the central exhaust passage; a second expansion chamber in a downstream portion of the exhaust system and in fluidic communication with the central exhaust passage and the first expansion chamber, forming a continuous expansion chamber throughout a length of the insert device.

Disclosed herein is a meta-muffler for reducing broadband noise. The meta-muffler includes: a flow pipe through which a fluid flows; an outer barrel disposed outside the flow pipe to be spaced apart from the flow pipe; and multiple metastructures arranged in a flow direction of the fluid and each comprising an opening opened parallel to the flow direction of the fluid, a resonance chamber disposed between the flow pipe and the outer barrel and communicating with the flow pipe through the opening, and a neck adjustment member extending from the outer barrel toward the flow pipe to be spaced apart from the opening in the flow direction of the fluid. The meta-muffler can increase transmission loss of noise flowing through the flow pipe through maximization of energy loss of sound waves entering the resonance chamber of the metastructure and can effectively attenuate noise over a wide band ranging from low frequencies to high frequencies.

There is provided an exhaust device that purifies exhaust gas discharged from an engine through an exhaust pipe. The exhaust device includes: a chamber that forms an expansion chamber of the exhaust gas at a downstream side of the exhaust pipe; a partition wall that partitions the expansion chamber into a first expansion chamber and a second expansion chamber; an introduction pipe that enters the second expansion chamber from a downstream end of the exhaust pipe; and a catalyst interposed at an intermediate portion of the introduction pipe in the second expansion chamber. The partition wall is formed with a first opening connecting an outlet of the introduction pipe to the first expansion chamber and a second opening connecting the first expansion chamber to the second expansion chamber, and the second opening overlaps with the catalyst when viewed from a side of the first expansion chamber.

A vortex flow apparatus including a cylindrical housing that contains a fluid that flows in a swirling circular path. The apparatus may be utilized as a muffler for a combustion engine, a particle separator, or an energy conversion device that physically or chemically acts upon the fluid flow and particles contained within the apparatus. The housing defines an inlet opening that opens into the first end of the housing proximate a first end wall. An outlet tube defines an outlet opening through a first end wall. A projection is attached to a second end wall of the housing and extends into the housing. The outlet tube and projection are aligned with and centered relative to a central axis.

An exhaust gas duct system for an internal combustion engine includes an upstream, first exhaust gas pipe area (30), a downstream, second exhaust gas pipe area (34) adjoining the first exhaust gas pipe area (30) in a transition area (38) in an exhaust gas flow direction (G), and a liquid drain channel area (60) in the transition area. The drain channel area is open from the exhaust gas flow volume (78) in the first exhaust gas pipe area (30) or/and in the second exhaust gas pipe area (34) to a liquid collection volume (80).