A golf car includes an engine and a shroud that covers a cylinder body. The shroud communicates with a muffler cover, which covers a muffler. A silencer is provided at an outlet of the muffler. An elastic exhaust duct is connected to an exit end portion of the muffler cover. An undercover is located lower than the engine, and defines an underside of an engine room. The undercover includes an opening at a more rearward position than the muffler in a side view. The exhaust duct is routed above the undercover, includes a rearward end portion at the opening, and is fitted to the opening. Holders hold sound absorbing members on an inner circumferential surface of the exhaust duct.

The present disclosure provides an acoustic metamaterial-based muffler for exhaust noise reduction, including an exhaust flow body that is provided with an inlet through which exhaust gas of an internal combustion engine flows in on one side, and an outlet through which the exhaust gas flows out on the other side, and a flow passage for guiding a movement of the exhaust gas therein; and a plurality of noise reduction units that are sequentially disposed along a discharge direction of the exhaust gas inside the exhaust flow body to reduce noise in a specific frequency band in exhaust noise of the exhaust gas caused by the movement of the exhaust gas on the inside of the exhaust flow body.

The present disclosure provides an acoustic metamaterial-based muffler for exhaust noise reduction, including an exhaust flow body that is provided with an inlet through which exhaust gas of an internal combustion engine flows in on one side, and an outlet through which the exhaust gas flows out on the other side, and a flow passage for guiding a movement of the exhaust gas therein; and a plurality of noise reduction units that are sequentially disposed along a discharge direction of the exhaust gas inside the exhaust flow body to reduce noise in a specific frequency band in exhaust noise of the exhaust gas caused by the movement of the exhaust gas on the inside of the exhaust flow body.

A muffler assembly unit for an exhaust system of an internal combustion engine, especially in a vehicle, includes a muffler (42) with a muffler housing (10). The muffler housing (10) is elongated along a longitudinal axis of the housing. A housing jacket (40) encloses the muffler housing (10). At least one air guiding bulge (34) is provided on the housing jacket (40).

A muffler assembly unit for an exhaust system of an internal combustion engine, especially in a vehicle, includes a muffler (42) with a muffler housing (10). The muffler housing (10) is elongated along a longitudinal axis of the housing. A housing jacket (40) encloses the muffler housing (10). At least one air guiding bulge (34) is provided on the housing jacket (40).

A muffler for an exhaust system has a muffler housing with an inlet chamber fluidically connected an outlet chamber. The inlet chamber has an inlet pipe for supplying an exhaust gas stream into the inlet chamber, and the outlet chamber has an outlet pipe for discharging the exhaust gas stream from the outlet chamber, wherein the inlet pipe and the outlet pipe each have a first pipe portion and a second pipe portion. The inlet pipe and the outlet pipe in the respective first pipe portions are circumferentially impermeable to the exhaust gas stream and are circumferentially porous in the respective second pipe portions. The first pipe portions each have a predetermined length, such that a ?/4 resonator is formed between the respective first pipe portions and walls of the muffler housing associated with the respective first pipe portions.

A muffler for an exhaust system has a muffler housing with an inlet chamber fluidically connected an outlet chamber. The inlet chamber has an inlet pipe for supplying an exhaust gas stream into the inlet chamber, and the outlet chamber has an outlet pipe for discharging the exhaust gas stream from the outlet chamber, wherein the inlet pipe and the outlet pipe each have a first pipe portion and a second pipe portion. The inlet pipe and the outlet pipe in the respective first pipe portions are circumferentially impermeable to the exhaust gas stream and are circumferentially porous in the respective second pipe portions. The first pipe portions each have a predetermined length, such that a ?/4 resonator is formed between the respective first pipe portions and walls of the muffler housing associated with the respective first pipe portions.

A golf car includes an engine and a shroud that covers a cylinder body. The shroud communicates with a muffler cover, which covers a muffler. A silencer is provided at an outlet of the muffler. An elastic exhaust duct is connected to an exit end portion of the muffler cover. An undercover is located lower than the engine, and defines an underside of an engine room. The undercover includes an opening at a more rearward position than the muffler in a side view. The exhaust duct is routed above the undercover, includes a rearward end portion at the opening, and is fitted to the opening. Holders hold sound absorbing members on an inner circumferential surface of the exhaust duct.

A golf car includes an engine and a shroud that covers a cylinder body. The shroud communicates with a muffler cover, which covers a muffler. A silencer is provided at an outlet of the muffler. An elastic exhaust duct is connected to an exit end portion of the muffler cover. An undercover is located lower than the engine, and defines an underside of an engine room. The undercover includes an opening at a more rearward position than the muffler in a side view. The exhaust duct is routed above the undercover, includes a rearward end portion at the opening, and is fitted to the opening. Holders hold sound absorbing members on an inner circumferential surface of the exhaust duct.

A muffler, connected to an engine through an exhaust pipe, includes a shell serving as a muffler body, an inlet pipe configured to introduce exhaust gas from the engine into the shell, an outlet pipe configured to discharge the exhaust gas out of the shell, and a cap configured to be attached to a narrowed portion of the inlet pipe and control the direction in which the exhaust gas flows out. The cap is provided with an opening through which the exhaust gas passes and which regulates the direction in which the exhaust gas flows out.