A vehicle exhaust system includes a first component that receives exhaust gas output from an engine and a second component that is fluidly coupled to the first component to define an upstream portion of a vehicle exhaust system. A vehicle frame member includes an internal acoustic volume. A pipe connects the internal acoustic volume in parallel to the upstream portion of the vehicle exhaust system.

A silencer having an outer housing; and a central perforated tube through which air flows. The silencer further includes an additional perforated structure located between the central perforated tube and the outer housing, a first chamber is formed between the central perforated tube and the additional perforated structure, and the additional perforated structure is configured such that at least one second chamber is formed, which is at least partially located radially outside of the first chamber, where the second chamber is communicated with the first chamber by perforates. The disclosure further relates to a vehicle engine having the silencer. The silencer is compact in structure, and has a better broadband silencing effect.

A vehicle exhaust system includes a tubular component defining a primary exhaust gas flow path. At least one opening defined by the tubular component extends through an inner surface and an outer surface of the tubular component. A patch covers the at least one opening. The patch includes a plate disposed on the tubular component. The plate defines at least one flow channel to receive exhaust gases from the at least one opening and impart at least one directional change to the received exhaust gases. The plate further defines at least one outlet opening adapted to receive exhaust gases from the flow channel. A secondary exhaust gas flow path is defined through the at least one opening in the tubular component, the flow channel defined by the plate, and the outlet opening defined by the plate.

The dual inlet exhaust design for the flying device incorporates easy-to-assemble designs with low number of components, suitable for limited space and small volume requirements, good performance. The exhaust is designed as a three-chamber cylinder with two coaxial inlet pipes running through the two chambers on both sides, extending into the middle compartment. The width of the two inlet tubes in the middle compartment is different. The inlet pipe at the two compartments on both sides has a bore. The outlet tube is located in the middle compartment, deviating to the side with a smaller expansion inlet, with the longitudinal axis of the outlet tube passing through the inlet tube.

An exhaust gas purification device includes a pre-oxidation catalyst disposed in an exhaust gas passage and a muffler that is provided in such a manner as to surround the pre-oxidation catalyst, and discharges exhaust gas while reducing noise. The muffler has an inlet which is connected to an upstream side exhaust pipe and an outlet which is connected to a downstream side exhaust pipe. The exhaust gas purification device includes a downstream side purification device that is disposed in the exhaust gas passage, and accommodates a second oxidation catalyst and a particulate matter removing filter. The exhaust gas is discharged to the atmosphere after the exhaust gas flows through the downstream side purification device.

An exhaust-gas system for a vehicle having an internal combustion engine includes a Helmholtz resonator and two exhaust-gas lines extending toward the resonator. The resonator has two neck openings to a resonator volume. Each neck opening is coupled to one of the exhaust-gas lines, and the resonator is tuned to damp a dominant engine order.

Provided is a tail pipe in which a silencing effect at a discharge port is obtained. One aspect of the present disclosure is a tail pipe including: an inner tube including a discharge port configured such that an exhaust gas is discharged therefrom; an outer tube arranged so as to form a space between the outer tube and the inner tube by surrounding an outer peripheral surface of the inner tube, an upstream end of the outer tube in a flow direction of the exhaust gas being closed; and at least one communication hole allowing communication between an interior of the inner tube and the space.

A muffler devised particularly for a small, reciprocating-piston two-stroke internal combustion engine of the type used on unmanned aerial vehicles. The muffler comprises a body incorporating an inlet, an outlet, and a plurality of chambers for exhaust gas flow from the inlet to the outlet. The body is configured to present a compact profile for installation on the engine. The chambers are so configured that adjacent chambers communicate to facilitate exhaust gas flow from the inlet to the outlet via flow passages. The various chambers comprise an inner chamber, an outer chamber, and one or more intervening chambers disposed between the inner and outer chambers. The various chambers are disposed one about another in annular formation. This arrangement creates a long flow path from the inlet to the outlet incorporating various directional changes.

A variable valve for a muffler may include an actuator; a valve tube having an inlet into which exhaust gas is flowed, and a first outlet and a second outlet into which the exhaust gas is discharged, and installed in a middle of a tail pipe into which the exhaust gas is discharged from a muffler; and a valve body in a ball shape rotatably installed in the valve tube, and rotatable by a rotational force delivered from the actuator to block the inlet, or to communicate the inlet with a selected one of the first outlet and the second outlet according to a rotated state of the valve body.

An exhaust structure of a vehicle is provided that can ensure an arrangement space for a mounted component below a floor panel and prevent thermal damage to the mounted component by reducing sizes of an engine and an exhaust silencer. An exhaust structure of a vehicle includes: an engine disposed in an engine bay formed in a front part of a vehicle; a silencer that reduces noise of exhaust gas from the engine and discharges the exhaust gas outside; an exhaust pipe that couples the engine and the silencer; and a battery unit disposed behind the engine and below a floor panel, the silencer being disposed between the engine and the battery unit.