An exhaust passage including a protrusion which is less likely to receive heat from a gas and hence has high heat-resistance reliability is provided. An exhaust passage includes an exhaust pipe, and a protrusion continuously formed over a range of a part of an inner surface of the exhaust pipe in a circumferential direction thereof, the protrusion being inclined toward a direction in which the exhaust pipe extends, and being configured in such a manner that a cross-sectional area of the exhaust pipe becomes smaller toward a downstream side thereof, in which the exhaust passage further includes a convex part on an inner surface of the protrusion.

A turbine includes: an inner diameter side exhaust flow path; an outer diameter side exhaust flow path having a flow path cross-sectional area smaller than a flow path cross-sectional area of the inner diameter side exhaust flow path; an inner diameter side bypass flow path connecting the inner diameter side exhaust flow path and a discharge flow path; and an outer diameter side bypass flow path connecting the outer diameter side exhaust flow path and the discharge flow path, the outer diameter side bypass flow path having a flow path cross-sectional area larger than a flow path cross-sectional area of the inner diameter side bypass flow path.

Methods and systems are provided for a turbocharger. In one example, a method may include bypassing exhaust gases flowing to the turbocharger in response to a catalyst temperature being less than a threshold temperature. The bypassing includes opening a bypass valve and adjusting a position of one or more turbine nozzle vanes.

An exhaust manifold for use with an internal combustion engine including a body, one or more fluid passageways defined by the body, and a valve in fluid communication with at least one of the one or more fluid passageways. The valve of the exhaust manifold being adjustable between an open configuration and a closed configuration. The exhaust manifold also includes an actuator in operable communication with the valve and configured to adjust the valve between the open and closed configurations, and a heat shield at least partially positioned between the actuator and the one or more fluid passageways.

The present invention relates to a valve arrangement (100) for a multi-channel turbine (10), having a housing section (300) with a first volute (320), with a second volute (340) and with a connecting region (360) between the first volute (320) and the second volute (340), and having a valve body (110) for closing off the connecting region (360) in a closed position of the valve body (110). A wall region (370) of the housing section (300), which wall region is arranged in the connecting region (360) and is situated opposite the valve body (110) in the closed position, is configured to be optimized in terms of flow to increase, during operation of the valve arrangement (100), a rate of flow transfer of exhaust gas between the first volute (320) and the second volute (340) in an open position of the valve body (110).

A straddled vehicle having an engine unit supported by a vehicle body frame. The engine unit includes an engine body, a turbocharger, and an exhaust device. The exhaust device includes an exhaust pipe and a muffler that are connected to each other to form a portion of an exhaust passage, to allow the exhaust gas passed through the turbocharger to pass therethrough, and a first catalyst and a second catalyst that are arranged in this order along a direction in which the exhaust gas flows through the exhaust pipe. The exhaust pipe has an upstream end thereof connected to the turbocharger, a downstream end thereof connected to the muffler, and a corner section that is bent in at least a part thereof between a downstream end of the first catalyst and an upstream end of the second catalyst, the catalysts not being arranged in the corner section.

A straddled vehicle having an engine unit supported by a vehicle body frame. The engine unit includes an engine body, a turbocharger, and an exhaust device. The exhaust device includes an exhaust pipe and a muffler that are connected to each other to form a portion of an exhaust passage, to allow the exhaust gas passed through the turbocharger to pass therethrough, and a first catalyst and a second catalyst that are arranged in this order along a direction in which the exhaust gas flows through the exhaust pipe. The exhaust pipe has an upstream end thereof connected to the turbocharger, a downstream end thereof connected to the muffler, and a corner section that is bent in at least a part thereof between a downstream end of the first catalyst and an upstream end of the second catalyst, the catalysts not being arranged in the corner section.

The disclosure relates to a valve assembly 10 for controlling a volute connecting opening 324 of a multi-channel turbine 500. The valve assembly 10 comprises a housing portion 300, a valve body 100 and an internal lever 200. The housing portion 300 defines a first volute channel 312, a second volute channel 314 and a volute connecting region 320. The housing portion 300 further comprises a cavity 340. The cavity 340 is separated from the volutes 312, 314 and can be accessed from outside the housing portion 300 via a housing opening 342 which extends from outside the housing portion 300 into the cavity 340. The volute connection region 320 is located between the first volute channel 312 and the second volute channel 314 and defines a volute connecting opening 324. The valve body 100 is inserted in the cavity 340 of the housing portion 300 and comprises at least one fin 120. The internal lever 200 is coupled with the valve body 100 and configured to pivotably move the valve body 100 between a first position and a second position. In the first position of the valve body 100, the fin 120 blocks the volute connecting opening 324.

A turbine assembly comprising a housing comprising first and second volutes which define a respective first and second flow passage. A circumferential outlet portion of each volute is defined by first and second tongues. The housing further comprises a first aperture in which a vane assembly is received. The vane assembly comprises a plurality of vanes circumferentially distributed about a turbine wheel-receiving bore, each vane comprising a leading edge and a trailing edge. Each vane has a fixed orientation. The vanes comprise a first vane and a second vane. The first vane having its leading edge disposed in closest proximity to a tip of the first tongue. The second vane having its leading edge disposed in closest proximity to a tip of the second tongue. The leading edge of each vane at least partly overlaps the tip of the proximate tongue circumferentially.

A turbine includes: a housing including an accommodating portion accommodating a turbine impeller; a first turbine scroll flow path communicating with the accommodating portion; a second turbine scroll flow path communicating with the accommodating portion and having a volume larger than a volume of the first turbine scroll flow path; a valve seat having a first port and a second port, the first port communicating with the first turbine scroll flow path, the second port communicating with the second turbine scroll flow path and having an opening area smaller than an opening area of the first port; a valve configured to contact the valve seat; and a shaft holding the valve and arranged on a side opposite to the first port with respect to the second port.