Abstract: An exhaust turbocharger turbine wheel can include a hub that includes a nose, a backdisk with a shaft joint portion, and a rotational axis; blades that extend from the hub to define exhaust flow channels where each of the blades includes a leading edge, a trailing edge, a hub profile, a shroud profile, a pressure side, and a suction side; where the backdisk includes an outer perimeter radius measured from the rotational axis of the hub, an intermediate radius at the shaft joint portion measured from the rotational axis of the hub, and an annular recess disposed between the intermediate radius and the outer perimeter radius and defined in part by three-dimensional bolster regions, where each of the three-dimensional bolster regions includes a footprint and a height measured at least in part in a direction of the rotational axis of the hub.

Abstract: A turbocharger system includes a valve member with at least one valve passage. The valve member is supported for rotation about an axis of rotation between a first position, a second position, and a third position. The axis of rotation is oriented transverse to flow within a first volute passage and a second volute passage. The valve passage, with the valve member in the first position, provides a cross flow path between the first volute passage and the second volute passage and provides a bypass flow path from at least one of the first and second volute passages and a bypass passage. In the second position, the valve passage provides the cross flow path, and the valve member substantially prevents flow along the bypass flow path. The valve member, in the third position, substantially prevents flow along the cross flow path and the bypass flow path.

Abstract: An exhaust turbocharger turbine wheel can include a hub that includes a nose, a backdisk with a shaft joint portion, and a rotational axis; blades that extend from the hub to define exhaust flow channels where each of the blades includes a leading edge, a trailing edge, a hub profile, a shroud profile, a pressure side, and a suction side; where the backdisk includes an outer perimeter radius measured from the rotational axis of the hub, an intermediate radius at the shaft joint portion measured from the rotational axis of the hub, and an annular recess disposed between the intermediate radius and the outer perimeter radius and defined in part by three-dimensional bolster regions, where each of the three-dimensional bolster regions includes a footprint and a height measured at least in part in a direction of the rotational axis of the hub.

Abstract: A turbocharger has a meridionally divided scroll comprising a first scroll and a second. A dividing wall that separates the two scrolls from each other has an evolutive thickness distribution as a function of angular location about a rotational axis of the turbine. In an embodiment, the dividing wall has a V-shape, and the included angle of the V-shaped dividing wall varies from a maximum value at a 0° angular location to a minimum value at a 360° angular location. As such, the thickness of the dividing wall correspondingly varies from a maximum value at the 0° angular location to a minimum value at the 360° angular location.

Abstract: A turbocharger system includes a valve member with at least one valve passage. The valve member is supported for rotation about an axis of rotation between a first position, a second position, and a third position. The axis of rotation is oriented transverse to flow within a first volute passage and a second volute passage. The valve passage, with the valve member in the first position, provides a cross flow path between the first volute passage and the second volute passage and provides a bypass flow path from at least one of the first and second volute passages and a bypass passage. In the second position, the valve passage provides the cross flow path, and the valve member substantially prevents flow along the bypass flow path. The valve member, in the third position, substantially prevents flow along the cross flow path and the bypass flow path.

Abstract: A turbocharger system includes a valve member disposed between plural volute passages of a turbine section and a wastegate. The valve member is supported for rotation about an axis of rotation between various positions. The valve member, in a first position, provides a cross flow path between the first volute passage and the second volute passage and provides a bypass flow path from at least one of the first and second volute passages to the wastegate. In a second position, the valve member provides the cross flow path and substantially prevents flow along the bypass flow path. In a third position, the valve member substantially prevents flow along the cross flow path and the bypass flow path. The valve member includes at least internal one valve passage and plural apertures that fluidly connect or alternatively fluidly disconnect the volute passages and wastegate in the first, second, and third positions.

Abstract: A turbocharger has a meridionally divided scroll comprising a first scroll and a second. A dividing wall that separates the two scrolls from each other has an evolutive thickness distribution as a function of angular location about a rotational axis of the turbine. In an embodiment, the dividing wall has a V-shape, and the included angle of the V-shaped dividing wall varies from a maximum value at a 0° angular location to a minimum value at a 360° angular location. As such, the thickness of the dividing wall correspondingly varies from a maximum value at the 0° angular location to a minimum value at the 360° angular location.

Abstract: A turbocharger including a turbocharger housing, a rotor and a heat shroud. The turbocharger housing includes a turbine housing affixed to a bearing housing. The rotor includes an axial turbine wheel with a hub, and a shaft extending through the bearing housing. The hub defines a back-disk surface that faces the bearing housing, and the bearing-housing defines an outer surface facing the turbine hub. The turbine housing forms a radial scroll, and the heat shroud forms a curved portion turning that radial scroll direction to an axial direction. The heat shroud establishes a back-disk cavity between a bearing-housing turbine-end-wall outer surface, the turbine-wheel back-disk surface, the curved portion of the heat shroud, and a cylindrical outer surface of a turbine-end portion of the shaft. The heat shroud includes flat ribs within the back-disk cavity to impede the circumferential flow of exhaust gas within the back-disk cavity.

Abstract: A turbocharger turbine having housing walls defining a diffuser. Within the diffuser, a center body within the diffuser is supported by de-swirl vanes extending from the diffuser wall. The center body forms a de-swirl passageway having an increasing mean diameter of flow from an upstream end of the center body to a leading edge of the de-swirl vanes. A trailing edge of the de-swirl vanes is near the downstream end of the center body. Annular-type guide vanes surround the center body within the de-swirl passageway. A wastegate system is configured to vent wastegate flow into the diffuser through injection ports on the de-swirl vanes, annular guide vanes and/or center body.

Abstract: A turbocharger system includes a valve member with at least one valve passage. The valve member is supported for rotation about an axis of rotation between a first position, a second position, and a third position. The axis of rotation is oriented transverse to flow within a first volute passage and a second volute passage. The valve passage, with the valve member in the first position, provides a cross flow path between the first volute passage and the second volute passage and provides a bypass flow path from at least one of the first and second volute passages and a bypass passage. In the second position, the valve passage provides the cross flow path, and the valve member substantially prevents flow along the bypass flow path. The valve member, in the third position, substantially prevents flow along the cross flow path and the bypass flow path.

Abstract: A turbocharger turbine having housing walls defining a diffuser. Within the diffuser, a center body within the diffuser is supported by de-swirl vanes extending from the diffuser wall. The center body forms a de-swirl passageway having an increasing mean diameter of flow from an upstream end of the center body to a leading edge of the de-swirl vanes. A trailing edge of the de-swirl vanes is near the downstream end of the center body. Annular-type guide vanes surround the center body within the de-swirl passageway. A wastegate system is configured to vent wastegate flow into the diffuser through injection ports on the de-swirl vanes, annular guide vanes and/or center body.

Abstract: A turbocharger including a turbocharger housing, a rotor and a heat shroud. The turbocharger housing includes a turbine housing affixed to a bearing housing. The rotor includes an axial turbine wheel with a hub, and a shaft extending through the bearing housing. The hub defines a back-disk surface that faces the bearing housing, and the bearing-housing defines an outer surface facing the turbine hub. The turbine housing forms a radial scroll, and the heat shroud forms a curved portion turning that radial scroll direction to an axial direction. The heat shroud establishes a back-disk cavity between a bearing-housing turbine-end-wall outer surface, the turbine-wheel back-disk surface, the curved portion of the heat shroud, and a cylindrical outer surface of a turbine-end portion of the shaft. The heat shroud includes flat ribs within the back-disk cavity to impede the circumferential flow of exhaust gas within the back-disk cavity.

Abstract: A turbocharger turbine having housing walls defining a diffuser. Within the diffuser, a center body within the diffuser is supported by de-swirl vanes extending from the diffuser wall. The center body forms a de-swirl passageway having an increasing mean diameter of flow from an upstream end of the center body to a leading edge of the de-swirl vanes. A trailing edge of the de-swirl vanes is near the downstream end of the center body. Annular-type guide vanes surround the center body within the de-swirl passageway. A wastegate system is configured to vent wastegate flow into the diffuser through injection ports on the de-swirl vanes, annular guide vanes and/or center body.

Abstract: A turbocharger turbine having housing walls defining a diffuser. Within the diffuser, a center body within the diffuser is supported by de-swirl vanes extending from the diffuser wall. The center body forms a de-swirl passageway having an increasing mean diameter of flow from an upstream end of the center body to a leading edge of the de-swirl vanes. A trailing edge of the de-swirl vanes is near the downstream end of the center body. Annular-type guide vanes surround the center body within the de-swirl passageway. A wastegate system is configured to vent wastegate flow into the diffuser through injection ports on the de-swirl vanes, annular guide vanes and/or center body.