A turbo blower operable in a surge area and, more particularly, a turbo blower operable in a surge area is provided. The turbo blower increases consistency of performance thereof and efficiency by preventing suspension thereof due to a temporarily generated surge by operating even in a surge area for a predetermined time in addition to a normal area in which the turbo blower normally operates.

A turbomachine includes a casing having an inlet end opposite an outlet end along a longitudinal axis of the casing; a shaft assembly provided within the casing, the shaft assembly extending from the inlet end to the outlet end; a plurality of rotating impellers extending radially outward from the shaft assembly; and a communication channel defined between two adjacent impellers to permit a backflow of fluid from a diffuser channel of a downstream impeller to a return channel of an adjacent upstream impeller.

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.

The present disclosure relates to a diffuser for a radial compressor. The diffuser may comprise a diffusor duct portion formed by first and second side walls that are arranged so as to diverge at least partially from one another in a direction of flow, a blade ring having a number of blades arranged at least partially in the diffusor duct portion with each blade having a pressure side and a suction side delimited by a blade leading edge and by a blade trailing edge of the respective blade, a number of pressure equalizing openings incorporated into at least one of the first and second side walls of the diffuser duct portion in a region where the first and second side walls diverge from one another with each of the pressure equalizing openings being arranged between the pressure side of one blade and the suction side of an adjacent blade of the blade ring, and a first annular duct arranged behind the pressure equalizing openings and fluidically connected to the diffuser duct portion via at least two of the pressure equalizing openings, such that a number of regions between two adjacent blades of the blade ring in the diffuser duct portion are fluidically connectable together.

A centrifugal compressor includes a compressor housing, an impeller wheel which compresses intake gas from an intake-air inlet, a plurality of guide vanes disposed circumferentially along an inner circumferential wall of the intake-air channel between the intake-air inlet and the impeller wheel to swirl the intake gas around the rotational axis, a central intake-air flow path formed at an inner side of the guide vanes to allow the intake gas to flow to the impeller wheel without passing through the guide vanes, and a guide-vane moving mechanism which simultaneously changes the inclination angle of the guide vanes. Guide vanes generate swirl flow at an inner circumferential housing portion of an impeller wheel to improve a surge margin and to restrict decrease in a choke flow rate.

A system includes a dynamic compressor, a variable frequency drive (VFD), and a controller. The dynamic compressor includes a motor having a driveshaft rotatably supported within the dynamic compressor, and a compression mechanism connected to the driveshaft and operable to compress a working fluid upon rotation of the driveshaft. The VFD includes a sensor configured to sense a current provided to the motor. The controller is connected to the motor and includes a processor and a memory. The memory stores instructions that program the processor to operate the motor using the VFD to compress the working fluid, receive signals representing the current from the VFD to the motor, and determine when a surge event has occurred based at least in part on the received signals representing the current from the VFD to the motor.

A system for bleeding air from a core flow path of a gas turbine engine is disclosed. In various embodiments, the system includes a bleed valve having a bleed valve inlet configured to receive a bleed air from a first access point to the core flow path and a bleed valve outlet; and an air motor having a first air motor inlet configured to receive the bleed air from the bleed valve outlet and a first air motor outlet configured to exhaust the bleed air, the air motor configured to pump the bleed air from the core flow path of the gas turbine engine.

A centrifugal compressor having a casing that houses an impeller allowing rotation about a rotational axis C, a gas channel, a treatment hollow part provided inside the casing, a first channel open to the gas channel on the downstream side of the blade leading edge of the impeller, a second channel open to the gas channel at the upstream side of the blade leading edge, a guide vane that imparts a swirl component in an opposite rotational direction of the impeller to gas discharged from the second channel, a constricting part that constricts the gas channel, and a rectifying part that rectifies gas in a direction that minimizes the swirl component about the rotational axis C and also increases the component in the direction of the rotational axis C.

The centrifugal compressor (1) includes: an impeller (3); and a casing (2) accommodating the impeller (3). The casing (2) includes: an inlet (6); an impeller-accommodating portion (14) in which the impeller (3) is disposed; an annular chamber (11) formed around the inlet (6); a downstream groove (13) communicating a downstream end portion of the annular chamber (11) with the impeller-accommodating portion (14); and an upstream groove (12) communicating an upstream end portion of the annular chamber (11) with the inlet (6). In addition, the downstream groove (13) is provided in a predetermined range in a circumferential direction of the impeller (3) so as to communicate with a high-pressure part to occur in part of the impeller-accommodating portion (14), and the upstream groove (12) is provided over the entire circumference of the inlet (6).

Embodiments provided herein are directed to systems and methods of re-injecting vaporized flash refrigerant from an economizer into a two-stage compressor. The injection can be through an injection port positioned after the first compression stage. The location of the injection may have a relatively low static refrigerant pressure. The injection port and/or an injection pipe of the economizer may be configured to pre-condition the vaporized flash refrigerant so that a flow velocity and/or direction of the vaporized flash refrigerant flow can be match a flow velocity and/or direction of the refrigerant in the refrigerant conduit.