A compressor includes: a shroud surface; a front-side inner peripheral surface formed on a front side of the shroud surface in the axial direction and disposed outward of a front end of the shroud surface in the radial direction; and at least one projection protruding from the front-side inner peripheral surface inward in the radial direction. A rear end of the at least one projection is configured to be connected to the front end of the shroud surface. The at least one projection is formed in a plate shape, and in a cross-sectional view along an axis of the impeller, has an inclined front edge extending obliquely to the axis of the impeller from a front end of the projection toward a rear side.

A centrifugal compressor for a chiller system includes a casing having an inlet portion and an outlet portion, a recirculation structure including a recirculation path and a recirculation discharge cavity, an impeller disposed downstream of the recirculation discharge cavity, a plurality of recirculation discharge guide vanes disposed to surround the recirculation discharge cavity, and a diffuser disposed in the outlet portion downstream of the impeller. The recirculation structure is configured to impart a swirl to a flow of refrigerant into the inlet portion. The recirculation path supplies the refrigerant from the diffuser to the recirculation discharge cavity. The recirculation path includes a recirculation pipe that introduces the refrigerant toward the plurality of recirculation discharge guide vanes. An annular groove is disposed between the recirculation pipe and the plurality of recirculation discharge guide vanes. An annular plate is disposed between the annular groove and the recirculation discharge cavity.

A fan case assembly adapted for use with a gas turbine engine includes a fan track liner and an annular case. The fan track liner extends circumferentially at least partway about a central axis of the gas turbine engine. The annular case is configured to support the fan track liner at a radial position relative to the central axis. The fan case assembly further includes an air recirculation duct configured to redirect air around the fan track liner.

An internal gear pump or motor includes inner and outer rotors that mesh together. An internal electric motor or generator may include a stator supported by a support element that passes through bearings of the outer rotor and the inner rotor may act as a rotor of the electric motor or generator. With or without the stator, the support element may support bearings of the inner rotor. The support element may be, for example, an eccentric shaft. Fluids may be supplied via the support element, if present, for cooling, lubrication or to flush a working fluid out of portions of the pump or motor, such as bearings. Flushing may also occur via channels in the housing with or without the presence of the support element. Axial faces of one of a pair of adjacent elements, for example the inner rotor and the outer rotor, may include portions for improved axial sealing and wearing in of the other of the pair. Fluid may enter and exit chambers between the inner and outer rotors by radial ports

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.

A compressor housing includes: when an intake side in an axial direction of the centrifugal compressor is defined as a front side, and a side opposite to the intake side in the axial direction is defined as a rear side, a shroud surface including a surface facing a tip of an impeller blade of the impeller with a predetermined gap; a front-side inner peripheral surface formed on the front side of the shroud surface in the axial direction and positioned on an outer side in a radial direction than a front end of the shroud surface; and plurality of grooves formed in the front-side inner peripheral surface at intervals in a circumferential direction wherein each of the plurality of grooves includes: an inclined portion whose depth gradually increases toward a rotation direction of the impeller; and a stepped portion formed at a downstream end of the inclined portion in the rotation direction.

A fan frame body with damping structure and a fan thereof. The fan frame body includes a fan frame main body having a first opening, a second opening, a flow way and a base section. The first and second openings are respectively positioned at the upper and lower ends of the fan frame main body. The flow way is disposed between the first and second openings in communication with the first and second openings. The base section is disposed at the second opening. A bearing cup and multiple static blades are perpendicularly disposed on the base section. Two ends of the static blades are respectively connected with the base section and the fan frame main body. Multiple damping structures are annularly disposed on an inner wall of the fan frame main body. The damping structures are raised body structures or recess structures.

An example centrifugal compressor includes a housing that defines an inlet chamber and includes first and second openings that define a recirculation passage in fluid communication with the inlet chamber. An impeller is disposed within the housing and is rotatable about a longitudinal axis to draw fluid into the inlet chamber. The first and second openings are at different axial locations along the longitudinal axis. A plurality of inlet guide vanes are rotatable and situated in the inlet chamber. The centrifugal compressor includes a ring and a controller for moving the ring along the longitudinal axis between a first position and a second position when rotating the inlet guide vanes. The ring obstructs at least one of the first and second openings more in the second position than in the first position.

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≤σ≤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 σ is constriction amount which is a difference between R1 and R2.

A sealing ring element of a turbomachine includes: a sealing portion with a first area and a second area, with the inner surface of a first area being at the same radial distance from the axis of the turbomachine. The sealing portion includes an annular cavity which opens into an inner surface of the second area and extends into the first area, the annular cavity defining an upstream lateral wall and/or a downstream lateral wall forming an angle which is strictly between 0 and 90°.