Abstract: A gas turbine engine includes rotor having a hub, and a plurality of blades extending generally radially from the hub. Each of the blades has an airfoil portion. The airfoil portion has a leading edge and a trailing edge defining a chordwise direction, and a root and a tip defining a spanwise direction. Only a sub-set of the blades has a cutback at at least one of the trailing edge and the leading edge. A method of designing and a method of assembling a rotor having noise reduction properties in a gas turbine engine is also presented.

Abstract: A compressor diffuser for a gas turbine engine includes a plurality of diffuser pipes each having a diverging tubular body defining a flow passage extending fully therethrough. The tubular body includes a first portion extending in a first direction, a second portion extending in a second direction different from the first direction, and a curved portion interconnecting the first portion and the second portion. At least one splitter vane extends into the flow passage and disposed at least partially within the curved portion of the tubular body.

Abstract: A centrifugal compressor having at least a diffuser is disclosed. The diffuser has an annular diffuser body having circumferentially spaced apart diffuser passages defining fluid paths through the diffuser body. The diffuser also has a plurality of diffusion members mounted to the annular diffuser body. Each diffusion member has a member inlet in fluid communication with a diffuser passage and a member outlet. Each diffusion member defines an aerodynamic throat disposed between the member inlet and the member outlet. The diffuser also has a fluid injection assembly with multiple injection conduits. Each injection conduit extends between a conduit inlet configured to receive a flow of compressible fluid from a supply and a conduit outlet communicating with a corresponding diffusion member downstream of the aerodynamic throat. The compressible fluid is injected through the conduit outlet into the diffusion members.

Abstract: The centrifugal compressor described includes an impeller shroud which encloses the impeller and has a curved shroud surface that extends between an inducer portion and an exducer portion. The compressor includes one or more circumferential grooves in the shroud body within the exducer portion. Each groove has opposed wall segments spaced apart therefrom. The wall segments are inclined at a nonzero groove angle relative to a normal of the shroud surface in a direction opposite the fluid flow path along the shroud surface.

Abstract: A compressor for a gas turbine engine having a bleed air recirculation system includes a plurality of bleed holes extending through the shroud at a first axial location thereon substantially adjacent the blade tips. The bleed holes have a closed outer perimeter along their complete length. An annular bleed cavity surrounds the shroud and is in communication with outlet openings of the bleed holes. The bleed holes provide communication between said main gas flow passage and the bleed cavity. The bleed cavity includes exit passages having outlets disposed in said shroud at a second axial location which is upstream of both the first axial location and the leading edge of the blades of the rotor. Bleed air is passively bled from the main gas flow passage via the bleed holes, recirculated through the bleed cavity and re-injected back into the main gas flow passage at the second axial location.

Abstract: A rotor for a gas turbine engine includes a plurality of radially extending blades, each having a remote blade tip defining an outer tip surface, and a leading edge defined between opposed pressure and suction side airfoil surfaces. A shroud circumferentially surrounds the rotor, and a radial distance between an inner surface of the shroud and the outer tip surface of the blades defines a radial tip clearance gap therebetween. The tip of each of the blades has a pressure side edge formed at the intersection between the outer tip surface and the pressure side airfoil surface, and a suction side edge formed at the intersection between the outer tip surface and the pressure side airfoil surface. The suction side edge has a larger radius of curvature than the pressure side edge, thereby reducing the amount of tip leakage flow through the radial tip clearance gap.