Abstract: Suction surfaces of blades of this radial turbine each have: a leading edge side of blade tip including a leading edge and the boundary between the suction surface and the tip; and a trailing edge side of blade tip including a trailing edge and the boundary between the suction surface and the tip. The leading edge side of blade tip forms a concave curved surface which is recessed towards the side opposite to the rotation side in a radial view. The trailing edge side of blade tip forms a convex curved surface which protrudes towards the rotation side in a radial view.

Abstract: A turbine includes a housing including an inlet, an outlet, and a shroud section having a shroud surface extending between the inlet and the outlet; and a turbine impeller housed in the housing and including a hub and a plurality of blades disposed on an outer peripheral surface of the hub, each of the blades having a side edge extending along the shroud surface. The side edge of each of the blades has a side-edge upstream portion disposed on a side of the inlet, and a side-edge downstream portion disposed on a side of the outlet. The shroud surface has a shroud upstream portion disposed on the side of the inlet and extending along the side-edge upstream portion, and a shroud downstream portion disposed on the side of the outlet and extending along the side-edge downstream portion.

Abstract: A centrifugal compressor (P) is provided with: a casing (10) which forms an impeller inlet flow path (11), an impeller flow path (12), an impeller outlet flow path (13), and a scroll (14); and an impeller (3) which is arranged in the impeller flow path (11), wherein the casing (10) is provided with a casing body (15) and a heat conduction inhibiting part (16) which is disposed to heat conduction paths to the impeller inlet flow path (11) from at least the impeller outlet flow path (13) and the scroll (14) so as to inhibit heat conduction to the impeller inlet flow path (11) from at least the impeller outlet flow path (13) and the scroll (14).

Abstract: A compressor impeller includes: a compressor impeller body portion including a boss portion and a plurality of vane portions disposed at intervals in a circumferential direction on a peripheral surface of the boss portion; and a heat shield portion disposed on a side of a back surface of the boss portion and configured to rotate with the compressor impeller body portion

Abstract: A rotating machine includes a rotating body configured to rotate around a central axis, and a casing configured to accommodate at least a part of the rotating body, and the casing, includes a main section made of a metallic material, and a high-porosity section made of the same material as the main section and having a porosity higher than the main section.

Abstract: A variable geometry turbocharger includes: a turbine rotor; and a variable nozzle mechanism for adjusting a flow of exhaust gas to the turbine rotor from a scroll flow passage formed on a radially outer side of the turbine rotor. The variable nozzle mechanism includes: a nozzle vane disposed in an exhaust gas flow passage for guiding the exhaust gas to the turbine rotor from the scroll flow passage; a support wall forming a flow passage wall on a first side of the exhaust gas flow passage with respect to an axial direction of the turbine rotor and supporting the nozzle vane rotatably in a cantilever fashion; and a non-support wall forming a flow passage wall on a second side of the exhaust gas flow passage with respect to the axial direction. Of an end surface of the nozzle vane on a side of the non-support wall, an edge portion on a side of a pressure surface includes a non-support-wall side linear portion formed to have a linear shape.

Abstract: A fixed vane turbocharger includes: an impeller; a housing including, inside thereof, an impeller housing space which accommodates the impeller, a scroll flow passage formed on a radially outer side of the impeller, and a communication flow passage which brings the impeller housing space and the scroll flow passage into communication; and at least one fixed vane unit disposed in the communication flow passage and fixed to a portion of the housing on an inner side of the scroll flow passage with respect to a radial direction of the impeller. Each of the at least one fixed vane unit includes at least two vane portions and a coupling portion coupling the two vane portions, and is formed of a single sheet metal member.

Abstract: A turbine for a turbocharger includes: a turbine impeller coupled to a compressor impeller via a rotational shaft; a turbine casing disposed so as to cover the turbine impeller, the turbine casing including a scroll flow passage and a scroll outlet portion disposed on an inner side, in a radial direction, of the scroll flow passage, for guiding exhaust gas from the scroll flow passage to the turbine impeller; and a back-surface side member disposed so as to face a back surface of the turbine impeller. The back-surface side member includes a protruding portion disposed on an impeller facing surface which faces the back surface of the turbine impeller, the protruding portion protruding toward the back surface and extending in a circumferential direction.

Abstract: A turbine impeller includes: a hub portion coupled to an end of a rotational shaft; a plurality of main blades disposed at intervals on a peripheral surface of the hub portion; and a short blade disposed between two adjacent main blades among the plurality of main blades. An inter-blade flow channel is formed between the two adjacent main blades so that a fluid flows through the inter-blade flow channel from an outer side toward an inner side of the turbine impeller in a radial direction. In a meridional plane, a hub-side end of a leading edge of the short blade is disposed on an inner side, in the radial direction, of a hub-side end of a leading edge of the main blade.

Abstract: A turbine blade configured to be coupled to a rotational shaft and rotated around an axis includes: a hub having a hub surface which is inclined with respect to the axis in a cross section along the axis; a rotor blade disposed on the hub surface; and at least one rib formed on a blade surface of the rotor blade, the at least one rib extending in a direction which intersects with a span direction of the rotor blade in a meridional plane of the rotor blade.

Abstract: An object is to provide a turbine housing with a simple structure whereby it is possible to reduce flow resistance of exhaust gas and improve efficiency of a turbocharger. A turbine housing made by casting has an opening part formed on a hub side of a scroll part, the opening part having a radius R2 which satisfies a relationship R1<R2, provided that R1 is a radial directional distance from an axis of a turbine wheel to a tip of a shroud part and R2 is a radial directional distance from the axis to an inner peripheral edge of a hub-side wall surface of the scroll part. A roughness of a flow-path surface in a region A is smaller than in a region B, provided that the region A is a predetermined range from the tip of the shroud part and the region B is a predetermined range adjacent to the region A, among flow-path surfaces of the shroud part and the scroll part facing a scroll flow path on an outer side, in a radial direction, of the tip of the shroud part.

Abstract: When A is a flow-path cross-sectional area of the scroll part, and R is a distance from a centroid of a flow-path cross-section of the scroll part to a rotational axis of the turbine rotor blade, the scroll part is configured so that a first graph, having a horizontal axis representing an angular position ? in a circumferential direction of the scroll part and a vertical axis representing ratio A/R of the flow-path cross-sectional area A to the distance R, at least partially has a concave distribution. The scroll part includes a first section belonging to a first angular range in the circumferential direction, and a second section belonging to a second angular range downstream of the first angular range in the circumferential direction and having a smaller throat width than a throat width of the first section in an axial direction of the turbine rotor blade.

Abstract: The present invention includes: a turbine wheel 24 that is attached to a rotating shaft 14 and that has a plurality of turbine blades in the circumferential direction; scroll passages 15Aa, 15Ab that are formed in a spiral shape on the outside of the turbine wheel 24, and that are formed by being divided into a plurality of sections in the circumferential direction, the passages communicating with each other at the position of the turbine wheel 24 disposed between respective tongue sections 15Ac, 15Ad; and threads 51 that are provided on an back facing surface 41 disposed so as to oppose the back surface of the turbine wheel 24, the back surface being on the axially opposite side from the turbine blade side, and the linear parts extending from starting points 51a near the tongue sections 15Ac, 15Ad toward the rotating shaft 14 side so as to control the passage of fluid between the back surface and the back facing surface 41.

Abstract: A turbine casing includes: a shroud of a cylindrical shape defining an operational flow path between the shroud and a hub of a turbine rotor; a scroll outer peripheral wall continuing from an end side of the shroud and extending along a circumferential direction of the shroud; and a partition wall disposed inside the scroll outer peripheral wall and dividing an inside of the scroll outer peripheral wall into a first scroll flow path and a second scroll flow path disposed adjacent to each other in an axial direction of the shroud. The shroud, the scroll outer peripheral wall, and the partition wall are formed integrally by casting. The partition wall has a widening section which partially increases a communication area between at least two of the first scroll flow path, the second scroll flow path, and the operational flow path, in the circumferential direction of the shroud.

Abstract: An object is to is to reduce a leakage flow by reducing a clearance between an end surface of a nozzle vane, forming a variable nozzle mechanism of a variable geometry turbocharger, and a wall surface facing the end surface, and prevent the nozzle vane from being stuck due to contact of the end surface.

Abstract: A turbine is provided with a turbine rotor blade, and a turbine housing having a scroll part extending along a circumferential direction of the turbine rotor blade. The scroll part is configured such that an A/R ratio of a flow passage area A to a distance R between an axis of the turbine rotor blade and a flow passage center of the scroll part has a concave distribution at least in a part of a graph where an abscissa represents a circumferential position around the axis of the turbine rotor blade and an ordinate represents the A/R ratio.

Abstract: An expansion turbine including a turbine housing, a plurality of variable nozzles inside the turbine housing at intervals in a circumferential direction of the expansion turbine, the variable nozzles being configured to be rotatable about a rotation shaft, and a turbine wheel disposed rotatably inside the turbine housing, the turbine wheel including a plurality of turbine blades disposed downstream of the variable nozzles. The turbine housing has a first wall surface which faces tips of the turbine blades, and a second wall surface which faces the first wall surface across a flow path of the working fluid. A blade height of the variable nozzles at an outlet side is greater than a blade height of the turbine blades at an inlet side.

Abstract: This turbocharger (1A) is provided with: a rotating shaft (4); a turbine wheel (2); a compressor wheel (3); a bearing housing (6) provided with journal bearings (5A, 5B) for rotatably supporting a shaft (4), and a thrust bearing (8) for supporting the rotating shaft (4) in the center axis (C) direction thereof; and a turbine housing (31) in which the turbine wheel (2) is accommodated. A fluid supply section (70A) for supplying a fluid to the turbine wheel (2) is provided within the turbine housing (31) and said fluid presses the turbine wheel (2) toward a first end (4a) side.

Abstract: A turbocharger includes a gripping unit gripping a turbine-housing side flange portion and a bearing-housing side flange portion to couple a turbine housing and a bearing housing. In a state where the turbine housing and the bearing housing are coupled by the gripping unit, an elastic force in a direction to separate the turbine-housing side flange portion and the bearing-housing side flange portion from each other is applied to each of the turbine housing and the bearing housing.

Abstract: A rotating machine includes a rotating body configured to rotate around a central axis, and a casing configured to accommodate at least a part of the rotating body, and the casing, includes a main section made of a metallic material, and a high-porosity section made of the same material as the main section and having a porosity higher than the main section.