Abstract: A rotary machine blade (31) equipped with a clearance flow suppression blade section (34), the lean angle of which has one or more inflection points, and which is formed such that when the direction from a positive-pressure surface (31a) to a negative-pressure surface (31b) is taken as the normal direction, an inflection point (P1) of the lean angle positioned farthest toward the blade end (33) changes from the negative to the positive direction in the direction away from the blade end (33).

Abstract: An inclination angle between a direction perpendicular to a rotational axis and a tangential direction of a radially outer edge of a radially outermost concave arc portion, which is located outermost in the radial direction of an impeller among at least one concave arc portion, has a distribution along the circumferential direction of a scroll passage, and when a circumferential position in the scroll passage from a tongue of a scroll part to an outlet of the scroll passage is represented by a central angle about the rotational axis by using the tongue as a reference, the distribution of the inclination angle has a local minimum value or a minimum value in a range of the central angle of 30° to 210°.

Abstract: A centrifugal compressor includes: an impeller; a compressor inlet tube configured to guide air to the impeller; a scroll flow passage disposed on a radially outer side of the impeller; a bypass flow passage branching from the scroll flow passage via a branch port, the bypass flow passage connecting to the compressor inlet tube not via the impeller; and a bypass valve capable of opening and closing a valve port disposed in the bypass flow passage. The branch port has a non-circular shape when viewed along a normal N1 of the branch port passing through a center of the branch port.

Abstract: A rotary machine comprises a hub including: a blade-facing hub portion including a first blade-facing surface which faces a spherical hub-side end surface of a variable blade and which has a first spherical region having a spherical shape; an upstream hub portion disposed upstream of the blade-facing hub portion in an axial direction of the hub and having a first outer-peripheral surface being adjacent to the first blade-facing surface in the axial direction; and a downstream hub portion disposed downstream of the blade-facing hub portion in the axial direction and having a second outer peripheral surface being adjacent to the first blade-facing surface in the axial direction.

Abstract: A vaned diffuser provided on a downstream side of an impeller of a centrifugal compressor. The vaned diffuser includes: a diffuser passage forming portion having a hub-side surface and a shroud-side surface and forming an annular diffuser passage on a downstream side of the impeller; and a plurality of diffuser vanes provided in the diffuser passage at intervals in a circumferential direction of the impeller. A fillet is formed in a connection portion between each of the diffuser vanes and at least one of the hub-side surface and the shroud-side surface. Also, where R is a radius of the fillet and b is a vane height of each of the diffuser vanes, and a maximum value of R/b on a downstream side of a throat position of the diffuser passage is larger than a maximum value of R/b on an upstream side of the throat position of the diffuser passage.

Abstract: A centrifugal compressor includes an impeller, a compressor inlet pipe for guiding air to the impeller, a scroll passage disposed on an outer peripheral side of the impeller, and a bypass passage connecting the compressor inlet pipe and the scroll passage and bypassing the impeller. In a cross-section perpendicular to an axis of the compressor inlet pipe, when A1 is a connection portion on a downstream side in a rotational direction of the impeller of connection portions between an inner wall surface of the compressor inlet pipe and an inner wall surface of the bypass passage, C is a virtual circle constituting the inner wall surface of the compressor inlet pipe, and L1 is a tangent line of the virtual circle C at the connection portion A1, the inner wall surface of the bypass passage is formed from the connection portion A1 along the tangent line L1.

Abstract: A rotor includes: a hub; and a plurality of blades disposed on the hub. Each of the plurality of blades has a suction surface, a pressure surface, a leading edge, a trailing edge, a tip-side edge, and a hub-side edge. The suction surface has a first curved surface portion curved convexly toward the trailing edge such that the trailing edge is inclined to a pressure surface side in a first region which is a partial region, in a blade height direction of the blade, of a region connected to the trailing edge.

Abstract: A compressor housing accommodating a compressor wheel for compressing intake air supplied to an engine has therein an outer cooling passage extending along a circumferential direction on an outer circumferential side of a scroll passage of a spiral shape through which the intake air compressed by the compressor wheel flows, and an inner cooling passage extending along the circumferential direction on an inner circumferential side of the scroll passage. The inner cooling passage is separated from the outer cooling passage by a separation wall extending along the circumferential direction.

Abstract: A pipe connection structure according to an embodiment of the present invention includes: two inlet pipes through which a gas is capable of flowing; a connection pipe to which respective outlet-side end portions of the two inlet pipes are connected at a distance; and an outlet pipe connected to the connection pipe at an opposite side to a side where the two inlet pipes are connected to the connection pipe, the outlet pipe being capable of being in communication with the two inlet pipes via a space section inside the connection pipe. The two inlet pipes include a first inlet pipe disposed on a first side and a second inlet pipe disposed on a second side, in a width direction of the connection pipe, across a middle of connection positions of the two inlet pipes to the connection pipe. The outlet pipe is connected to a position offset toward the second side in the width direction of the connection pipe.

Abstract: A centrifugal compressor includes an impeller and a casing, the casing includes a scroll part forming a scroll flow passage and a diffuser part forming a diffuser flow passage. The diffuser part includes: a first diffuser portion belonging to a first angular range in a circumferential direction of the impeller; and a second diffuser portion belonging to a second angular range downstream of the first angular range in a flow direction of the scroll flow passage, of the angular range in the circumferential direction of the impeller, the second diffuser portion having an outer radius R2 which is defined along a reference circle centered at a rotational center of the impeller. An outer radius R1 of the first diffuser portion in the first angular range is smaller than the outer radius R2 of the second diffuser portion in the second angular range.

Abstract: An impeller for a centrifugal compressor includes a plurality of blades arranged around a hub, and on a trailing edge of the blade, a blade angle at a first position on a shroud side from a center position in a span direction of the blade is larger than a blade angle at a second position on a hub side from the center position.

Abstract: The present invention provides a casing for a radial compressor including: a scroll portion which is disposed on an outer circumferential side of an impeller and an intake portion and extends in a circumferential direction, has a discharge port opening in a circumferential direction and a scroll flow path through which the gas from the impeller flows toward the discharge port, and includes a resin material having a gradually increasing external shape dimension; and a plurality of ribs which connect an outer circumferential surface of the intake portion and an outer surface of the scroll portion. The plurality of ribs are provided at intervals in the circumferential direction, an installation interval gradually decreases toward the discharge port in the circumferential direction, and a length dimension in a radial direction on the outer surface of the scroll portion gradually decreases.

Abstract: A scroll shape of a compressor forms into a spiral shape a flow path of fluid discharged from a diffuser provided on a downstream side of the compressor in a fluid flow direction. The scroll shape has a scroll outer diameter that is not constant in a circumferential direction. An increase degree of a ratio A/R is set to be increased in a range from a winding start position to a winding end position of a scroll portion where A is a passage cross-sectional area of the scroll portion and R is a radius from a center of the compressor to a center of a passage cross section of the scroll portion.

Abstract: A scroll casing forms a scroll flow passage of a centrifugal compressor, and, provided that, in a cross section of the scroll flow passage, Eo is an outer end of the scroll flow passage in a radial direction of the centrifugal compressor, Ef is a front end of the scroll flow passage in an axial direction of the centrifugal compressor, and Mw is a middle point of a maximum flow-passage width Wmax of the scroll flow passage in the radial direction, a flow passage height H of the scroll flow passage in the axial direction gradually increases from a position of the outer end Eo to a position of the front end Ef with respect to the radial direction, and the scroll flow passage has a recirculation flow suppressing cross section in which the front end Ef is disposed on an inner side, in the radial direction, of the middle point Mw, in a section disposed at least partially in a region closer to a scroll start than a connection position of the scroll start and a scroll end.

Abstract: The present invention provides a casing for a radial compressor including: a scroll portion which is disposed on an outer circumferential side of an impeller and an intake portion and extends in a circumferential direction, has a discharge port opening in a circumferential direction and a scroll flow path through which the gas from the impeller flows toward the discharge port, and includes a resin material having a gradually increasing external shape dimension; and a plurality of ribs which connect an outer circumferential surface of the intake portion and an outer surface of the scroll portion. The plurality of ribs are provided at intervals in the circumferential direction, an installation interval gradually decreases toward the discharge port in the circumferential direction, and a length dimension in a radial direction on the outer surface of the scroll portion gradually decreases.

Abstract: A rotary machine satisfies at least one of Dr1<Dh1?Dr2 or Dc1?Dt1>Dc2. Dr1, Dh1, Dr2, Dc1, Dt1, and Dc2 are distances from a rotational center axis of a hub to an upstream end of a first blade-facing surface facing a hub-side end surface of a variable blade, an upstream end of the hub-side end surface when the blade angle is maximum, a downstream end of a first outer peripheral surface adjacent to an upstream side of the blade-facing surface, an upstream end of a second blade-facing surface facing a tip-side end surface of the variable blade, an upstream end of the tip-side end surface when the blade angle is minimum, and a downstream end of a first inner peripheral surface adjacent to an upstream side of the second blade-facing surface, respectively.

Abstract: A compressor impeller includes an impeller body which includes a boss portion and a plurality of compressor blades disposed on an outer peripheral surface of the boss portion, and a connection portion which is disposed on a side of a back surface of the impeller body and is configured to be connectable to one end of a rotational shaft. A ratio D1/D2 satisfies 0.18 or less, where D1 is a diameter of the boss portion on leading edges of the compressor blades, and D2 is a maximum outer diameter of the compressor blades.

Abstract: A rotary machine blade (31) equipped with a clearance flow suppression blade section (34), the lean angle of which has one or more inflection points, and which is formed such that when the direction from a positive-pressure surface (31a) to a negative-pressure surface (31b) is taken as the normal direction, an inflection point (P1) of the lean angle positioned farthest toward the blade end (33) changes from the negative to the positive direction in the direction away from the blade end (33).

Abstract: A centrifugal compressor includes an impeller including a hub and a plurality of blades disposed on an outer peripheral surface of the hub at intervals in a circumferential direction, and a casing accommodating the impeller and defining an inlet passage for introducing air along an axial direction of the impeller. An inner peripheral surface of the inlet passage includes a narrowed portion, and an inclined portion connected to a downstream side of the narrowed portion and having a radial distance from a rotational axis of the impeller gradually increasing toward the vicinity of tips of leading edges of the blades. Further, 0.01R1???0.1R1 is satisfied, where R1 is radial distance between a downstream end of the inclined portion and the rotational axis, R2 is radial distance between a downstream end of the narrowed portion and the rotational axis, and ? is constriction amount which is a difference between R1 and R2.

Abstract: A centrifugal compressor includes an impeller rotatably disposed and having a plurality of first blades and a shroud cover disposed on a leading edge side of the first blades partially in a rotational axis direction of the impeller and connecting the first blades circumferentially adjacent to each other. The shroud cover is shaped such that a position of at least one of an upstream edge or a downstream edge of the shroud cover in the rotational axis direction changes along a circumferential direction of the shroud cover.