An exhaust muffler includes a first muffler section connected to an exhaust pipe and a second muffler section connected to the first muffler section. Exhaust gases delivered from the exhaust pipe are discharged from the first muffler section and the second muffler section out of the exhaust muffler. The first muffler section includes a tubular member made up of an inner pipe to which the exhaust pipe is connected and an outer pipe covering the inner pipe, and a connector connecting the tubular member and the second muffler section to each other. The first muffler section has a first expansion chamber defined therein between the inner pipe and the outer pipe. The inner pipe houses therein a valve for changing an amount of exhaust gases passing through the inner pipe. The first muffler section includes a curved portion that is curved vertically as viewed in side elevation of the vehicle. The exhaust muffler has a second expansion chamber defined in the second muffler section rearward and upward of the first muffler section, the second expansion chamber having a cross-sectional area larger than a cross-sectional area of the first expansion chamber. There is thus provided an exhaust device for an internal combustion engine, which includes a muffler compact in a longitudinal direction thereof.

Methods and systems are provided for diagnostics of an exhaust tuning valve during vehicle-off conditions. In one example, the engine may be reverse rotated, unfueled while the position of the exhaust is varied and an intake air flow is estimated at each position of the exhaust tuning valve. The exhaust tuning valve may be diagnosed based on a change in air flow with the variation in the position of the exhaust tuning valve.

An exhaust system for an internal combustion automotive engine, comprising: a left exhaust tract connected or to be connected to a left group of cylinder of the internal combustion automotive engine and a right exhaust tract connected or to be connected to a right group of cylinder of the internal combustion automotive engine, the left and right exhaust tracts, each comprising a branching structure defining a tract inlet, at least one exhaust outlet directly or indirectly opening into atmosphere, and an interconnecting outlet interconnecting said left and right exhaust tracts, wherein said interconnecting outlets are interconnected with each other by a common exhaust gas cleaning and/or silencing device downstream said interconnecting outlets such that exhaust gas flows coming from said interconnecting outlets are unified within said common exhaust gas cleaning and/or silencing device.

Exhaust systems for handling multiple effluent streams are described. Some embodiments include pressure drops to prevent perturbations from one effluent source from affecting a second effluent source. Some embodiments incorporate an exhaust assembly with multiple inlets and pumps and a single outlet. The exhaust assembly includes shared auxiliary components like purge and cooling systems.

A system for regulating performance characteristics of a vehicle includes an engine configured to output an exhaust gas. The system further comprises an emissions system in fluid communication with the engine, the emissions system configured to clean the exhaust gas. The system further comprises a valve system in fluid communication with the emissions system, the valve system configured to regulate a flow of the exhaust gas. The valve system comprises a vane movable between a forward open position, a closed position, and a rear open position. The valve system further comprises a biasing member configured to bias the vane in the forward open position. The valve system further comprises a bypass channel configured to provide a bypass flow path for the exhaust gas to control a backpressure on the vane.

A muffler valve device for a vehicle may include a chamber fixed at a surface of the wall, a guide rod provided in the chamber and attached at the surface of the wall, a fixing member attached at one end portion of the guide rod and fixing the chamber, a valve disposed slidably on the guide rod between the surface of the wall and the fixing member, and an elastic member located between the valve and the fixing member to provide an elastic force to the valve.

A marine propulsion device includes an internal combustion engine powering the marine propulsion device and an engine compartment containing the engine. A primary exhaust passageway routes exhaust gas away from the engine and out of the engine compartment. A sound enhancement assembly communicates with the primary exhaust passageway. The sound enhancement assembly includes a sound enhancement device tuned to amplify exhaust sounds of a predetermined frequency and a sound duct downstream of the sound enhancement device that transmits the amplified exhaust sounds to an area outside the engine compartment. The sound enhancement device isolates the sound duct from the exhaust gas. A method for modifying sounds produced by an exhaust system of the internal combustion engine is also disclosed.

Methods and systems are provided for diagnostics of an exhaust tuning valve during vehicle-off conditions. In one example, the engine may be reverse rotated, unfueled while the position of the exhaust is varied and an intake air flow is estimated at each position of the exhaust tuning valve. The exhaust tuning valve may be diagnosed based on a change in air flow with the variation in the position of the exhaust tuning valve.

An exhaust gas flap, especially for the exhaust gas stream of an internal combustion engine, includes a flap tube (24), a flap diaphragm (26). The flap diaphragm (26) is carried in the interior of the flap tube (24) on a pivot shaft (18), rotatable about a pivot axis (A). The flap diaphragm (26) has at least one flap diaphragm part (28, 30) and a mounting area (40) enclosing the pivot shaft (18) in at least some areas. A wing stop (42, 44) is provided at an inner circumferential area of the flap tube (24) in association with at least one flap diaphragm part (28, 30). A recess (60, 62, 64, 66) at the flap diaphragm (26), receiving a circumferential end area (48, 50) of a wing stop (42, 44), is provided in at least one axial end area of the mounting area (40).

Disclosed is a silencer for fuel cell vehicles. The silencer for fuel cell vehicles includes a housing having an inlet configured to receive air and hydrogen flowing into the housing therethrough, an outlet, and a condensation water drain hole configured to discharge condensation water to the outside therethrough, a distribution plate disposed in the housing and having distribution holes to distribute air and hydrogen flowing into the housing, a rotary plate disposed in the housing closer to the outlet than the distribution plate, a motor connected to the rotary plate to rotate the rotary plate, and an anti-freezing unit extending from one end of the rotary plate to the condensation water drain hole.