A blower apparatus includes a motor portion having a central axis extending in a vertical direction; an impeller arranged above the motor portion, joined to a rotating portion of the motor portion, and arranged to rotate to send a gas from above radially outward; an impeller cover portion including an inner surface arranged to cover an outer circumference of the impeller and an upper side of an outer edge portion of the impeller, and further including an air inlet defined in a center thereof; a body cover portion joined to the impeller cover portion, arranged to cover an outer circumference of the motor portion, and arranged to define a tubular space between the body cover portion and a housing tubular portion defining an outer surface of the motor portion and extending in the vertical direction to assume a tubular shape; and a plurality of guide vanes arranged in a circumferential direction in the tubular space, and each of which is arranged to extend in a radial direction between an inner surface of the body cover portion and the housing tubular portion. Each of the guide vanes includes a guide vane upper portion arranged on an upper side, and a guide vane lower portion arranged on a lower side of the guide vane upper portion. The guide vane upper portion is inclined to a greater degree with respect to an axial direction than the guide vane lower portion. A lower end of the guide vane is arranged forward of an upper end of the guide vane with respect to a rotation direction of the impeller. The lower end of at least one of the guide vanes is arranged above a lower end of the housing tubular portion.

Disclosed are a fan motor and a vacuum cleaner which include a blowing fan and a plurality of diffuser blades disposed at a radially outer side of the blowing fan and circumferentially spaced apart from each other. Outer end portions of the plurality of diffuser blades include a spoiler portion formed obliquely to an outward direction with respect to an extending direction of the diffuser blades, so that a flow separation of air flowing across an outer surface of the diffuser blade is reduced. Accordingly, the suction force of the fan motor increases.

A compressor comprising: a casing; an upstream impeller and a downstream impeller for rotation in the casing; a diaphragm comprised of an internal portion and an external portion; an upstream diffuser fluidly coupled to an outlet of the upstream impeller; a return channel fluidly coupled to the upstream diffuser and to an inlet of the downstream impeller, the return channel has a plurality of return-channel blades connecting the internal and external diaphragm portions; and a downstream diffuser fluidly coupled to an outlet of the downstream impeller is disclosed. A first coolant passage is in the internal diaphragm portion and extends around an inner core, the first coolant passage being in heat-exchange relationship with the upstream diffuser and the return channel. A second coolant passage and third coolant passage are separated by a second inner core in the external diaphragm portion and in a heat-exchange relationship with the return channel and the downstream diffuser.

An electrical fan and an electric appliance are provided. The fans has a driving structure, an impeller, a wind hood and a diffuser. The impeller has a cover plate installed on the driving structure. The wind hood is covered on the impeller and has an air inlet and an air outlet communicated to each other. The diffuser is located at one end of the impeller facing the air outlet. The diffuser has a first protrusion connected to the driving structure. The first protrusion protrudes in a direction of the wind hood. The diameter of an end of the first protrusion adjacent the cover plate is smaller than the diameter of an end away from the cover plate. The diffuser has an inner ring arm connected to the first protrusion and an outer ring arm sleeved outside the inner ring arm.

A system for an aircraft is provided. The system includes a compressing device and at least one heat exchanger. The compressing device includes a compressor, a turbine downstream of the compressor, and an electric motor coupled to the turbine and the compressor. Further, the compressor includes a high rotor backsweep. The system can be an air conditioning system.

Centrifugal compressors can incorporate a side stream flow of intermediate pressure vapor between stages of that compressor. The side stream flow can be controlled by a side stream injection port controlled by a throttle ring disposed between stages of the compressor. The throttle ring can allow or obstruct flow through the side stream injection port. The throttle ring can extend and retract in a direction substantially perpendicular to the direction of flow from the first stage impeller to the second stage impeller. A method of operating a centrifugal compressor can include actuating a throttle ring by rotating a drive ring to adjust a flow of interstage fluid into the second stage impeller.

A compressor includes an impeller having a rotational axis. An annular diffuser is provided around the rotational axis to surround the impeller in order to decelerate the fluid discharged from the impeller in a centrifugal direction with respect to the rotational axis. The annular diffuser includes first vanes and second vanes. The first vanes are arranged in a first blade row extending in a circumferential direction around the rotational axis such that two adjacent vanes among the first vanes do not define a throat therebetween viewed along the rotational axis. The second vanes are arranged in a second blade row which extends in the circumferential direction and which is provided farther than the first blade row in the centrifugal direction from the rotational axis. A number of the second vanes is two times or more as large as a number of first vanes.

A fan (radial or axial fan), with an impeller and with a preguide device in the flow path in front of the impeller, preferably in front of the inlet region of an inlet nozzle, has the preguide device as a preguide grid with webs and/or guide vanes which are arranged and shaped such that flow influencing in the circumferential direction occurs for a substantially swirl-free inflow.

Three-dimensional (3D) return vane for a multistage centrifugal compressor. The return channel vane extends upstream to a region proximate the bend apex of the return channel. In each point of the return channel vane, the angle “beta” is defined as the acute angle between the tangent to the local camberline and the local circumferential direction. At each normalized position between leading edge and trailing edge, the local twist of the return channel vane is defined as the algebraic difference between the angles beta at the two points at hub and shroud having said normalized position. When moving in streamwise direction from leading edge to trailing edge, the twist first decreases, reaching an algebraic minimum, then increases, reaching an algebraic maximum, then decreases again. However, the absolute twist of the algebraic minimum is larger than the absolute twist of the algebraic maximum.

A radial compressor for a compressor arrangement comprising the radial compressor and an axial compressor includes an inlet flow channel bounded by a radially inner hub contour and a radially outer housing contour, in which inlet guide blades are arranged. Via the inlet flow channel a medium to be compressed is supplied to an impeller having moving blades. The inlet flow channel runs diagonally to an axis of rotation of the impeller.