An exhaust muffler for an internal combustion engine includes a housing. A plurality of partitions are disposed within the housing, defining a plurality of chambers. An inlet pipe and an outlet pipe are also disposed within the housing and both the inlet and outlet pipes include a perforated region. The perforated region permits fluid communication between the inlet pipe, outlet pipe and the plurality of chambers. To attenuate engine noise, the perforated regions of the inlet and outlet pipes are positioned at opposite ends of the housing, forcing the exhaust gas to pass through each of the plurality of partitions and chambers, thereby damping the sound waves with minimum effect on engine back pressure levels. Alternatively, the perforated regions of the inlet and outlet pipes may be aligned in a cross-flow chamber.

The disclosed inventive concept provides a further achievement in efforts to produce a tunable exhaust sound for a vehicle. The system provides a tunable exhaust system including a tunable resonator and a pair of tunable mufflers. The tunable resonator includes a housing including first, second and third expansion chambers. A pair of bank-by-bank exhaust conduits extends through the housing. At least one of the conduits includes a band of peripheral perforations within the first expansion chamber. The band is formed at an angle relative to the long axis of the conduit on which it is formed. The mufflers include inlet and outlet pipes. At least one of the outlet pipes includes a variable exhaust gas flow assembly. The variable exhaust gas flow assembly includes a vane shaft, an exhaust gas regulating vane attached to the vane shaft, and a vane actuator for regulating the position of the vane shaft.

An exhaust muffler for an exhaust system of an internal combustion engine, especially for a vehicle, includes a muffler housing with a flow volume (42), through which exhaust gas can flow, an exhaust gas inlet (28) and an exhaust gas outlet (36). A first resonator chamber (44) is open towards the flow volume (42) via a first resonator neck (68). A second resonator chamber (46) is open towards the flow volume (42) via a second resonator neck (74). A resonator pipe (52) provides the first resonator neck (68) and the second resonator neck (74).

An acoustic attenuator for damping pressure vibrations in an exhaust system of an engine, the acoustic attenuator having a body which is provided with a gas inlet and a gas outlet at opposite ends thereof, and a gas passage duct arranged between the inlet and the outlet inside the body, where in the body encloses a first resonator chamber and a second resonator chamber. The body is provided with a common inlet communicating with the first and the second resonator chambers, and the resonator chambers are arranged to extend from the common inlet towards the opposite ends of the body.

An apparatus for engine exhaust sound attenuation includes a housing, a plurality of baffle plates arranged within the housing. The baffle plates are disposed apart from each other to define a plurality of intermediate chambers. The plurality of intermediate chambers includes a first resonant chamber proximate to the outlet chamber, a second resonant chamber proximate to the inlet chamber, a first intermediate chamber proximate to the second resonant chamber, and a second intermediate chamber proximate to the first intermediate chamber and the first resonant chamber. An inlet tube and an outlet tube are included. A first tube directs a flow of exhaust from the inlet chamber to one of the plurality of intermediate chambers via an interior of the first tube. Additionally, a second tube directs the flow of exhaust from a second one of the plurality of intermediate chambers to the outlet chamber via an interior of the second tube.

An acoustic damper includes a low porosity layer section and a housing. The low porosity layer section is formed in a liner of a gas turbine combustor and has an arrangement of elongated generally S-shaped slots formed therein. The housing has a plurality of feed apertures. The housing is coupled to the low porosity layer section thereby defining a cavity such that air outside the housing is configured to flow through the apertures and through the elongated generally S-shaped slots in the low porosity layer section, thereby transforming acoustic energy into thermal energy and aiding in providing an acoustic dampening effect for the gas turbine combustor during operation thereof.

A silencer for an exhaust gas system of a motor vehicle has an external housing that has at least one inlet opening and at least one outlet opening for exhaust gas. The silencer includes a silencer chamber and a filter monolith through which exhaust gas flows, and which is circumferentially surrounded by the silencer chamber. Also disclosed is a motor vehicle with at least one silencer.

A muffler generates a sporty and rhythmic sound for a vehicle. The muffler includes a housing, first and second baffles, an inlet pipe, and left and right exhaust pipes. The first and second baffles the housing interior into left, intermediate, and right chambers. The left and right chambers include a sound absorber and the inlet pipe extends from a front of the housing into the intermediate chamber. A first end of the left exhaust pipe is in the intermediate chamber, a second end of the left exhaust pipe penetrates the left chamber and extends out of the housing, and a plurality of first through-holes is in a portion of the left exhaust pipe in the left chamber. A first end of the right exhaust pipe is in the intermediate chamber, a second end of the right exhaust pipe penetrates the right chamber and extends out of the housing, and a plurality of second through-holes is in a portion of the right exhaust pipe in the right chamber. Exhaust gas introduced through the inlet pipe is discharged from the housing through the left and right exhaust pipes.

A muffler for a vehicle, where the muffler comprises a partition wall that divides the interior in a first chamber and a second chamber, where an inlet pipe comprising a perforated section arranged in the first chamber and a closed section arranged in the first chamber, where the outlet opening of the inlet pipe is arranged in the second chamber, a first outlet pipe comprising an inlet opening arranged in the first chamber and an outlet opening arranged outside of the muffler, where the muffler comprises a second outlet pipe having an inlet opening arranged in the second chamber, and where the second outlet pipe is provided with an exhaust valve adapted to open or close the exhaust gas flow through the second outlet pipe. The advantage of the invention is that a muffler with an improved low frequency noise attenuation and low backpressure is provided.

The disclosed inventive concept provides a further achievement in efforts to produce a tunable exhaust sound for a vehicle. The system provides a tunable exhaust system including a tunable resonator and a pair of tunable mufflers. The tunable resonator includes a housing including first, second and third expansion chambers. A pair of bank-by-bank exhaust conduits extends through the housing. At least one of the conduits includes a band of peripheral perforations within the first expansion chamber. The band is formed at an angle relative to the long axis of the conduit on which it is formed. The mufflers include inlet and outlet pipes. At least one of the outlet pipes includes a variable exhaust gas flow assembly. The variable exhaust gas flow assembly includes a vane shaft, an exhaust gas regulating vane attached to the vane shaft, and a vane actuator for regulating the position of the vane shaft.