Abstract: A gas turbine engine compressor includes a rotor defining a central axis of rotation and a plurality of blades which project into an annular compressor gas flow passage, and a shroud circumferentially surrounding the rotor and having a radially inner surface adjacent to the blade tips. Bleed holes extend through the shroud adjacent the blade tips, each of the bleed holes having an inlet end disposed in the shroud radially inner surface and an outlet end disposed in a shroud radially outer surface. Bleed air removed from the annular gas flow passage flows through the bleed holes from the inlet to the outlet ends. The outlet end of each bleed hole is located circumferentially upstream of the inlet end relative to a direction of rotational flow in the annular gas flow passage driven by a direction of rotation of the rotor.

Abstract: A cooling device includes a plurality of passages extending through outer platforms of turbine vane segments for directing cooling air in a choked flow condition towards a downstream turbine shroud.

Abstract: An active tip clearance control (ATCC) system of a gas turbine engine includes an ejector to selectively drive an air flow passing through the ATCC system. A high pressure air flow as a motive flow of the ejector is controlled by a valve according to engine operation requirements.

Abstract: The gas turbine engine shroud comprises a plurality of circumferentially-disposed and concentric shroud segments. Each shroud segment has an arc-shaped platform with opposite ends, each end comprising an inter-segment seal slot, at least one slot extending substantially across each corresponding end and having a lengthwise-variable depth.

Abstract: A compressor bleed valve system for bleeding air from a gas turbine engine compressor comprises a bladder inflatable between at least a collapsed position and an expanded position for selectively opening and closing a compressor airbleed passage.

Abstract: A compressor comprises a casing having an inner surface surrounding a rotor assembly, the rotor assembly having a plurality of circumferentially spaced radially outwardly extending rotor blades, each blade having leading and trailing edges and a tip, the compressor further comprising at least one plasma actuator for suppressing rotating stall inception of the compressor, the at least one plasma actuator being mounted adjacent to the blade tips.

Abstract: Inlets are provided at a front end of inter-blade cavities for allowing coolant to flow therein to cool down the undersurface of the blade platforms as well as the rim of the disc of a rotor assembly.

Abstract: A blade containment of a gas turbine engine comprises a casing defining an annular wall radially spaced from and immediately surrounding a plurality of blades radially extending from a rotor, and at least one layer of metal wires wrapped around and directly attached to the annular wall.

Abstract: A vane assembly for a gas turbine engine comprising a number of radial loading elements disposed between lugs of the vane ring and the vane support, such as to generate a radial load force against the vane ring. The radial load force prevents unwanted relative movement between the vane ring and the vane support during operation of the gas turbine engine.

Abstract: A gas turbine engine expansion joint comprises first and second members having confronting faces defining a gap therebetween. At room temperature, the gap varies in accordance with the temperature distribution profile of the first and second members during normal engine operation.

Abstract: The interturbine duct (ITD) directs hot combustion gases from a high pressure turbine stage outlet to a low pressure turbine stage inlet in a gas turbine engine. The ITD comprises an outer wall and a heat resistant non-metallic resilient annular seal provided around an end of the outer wall that is adjacent to the high pressure turbine stage outlet.

Abstract: A segmented shroud ring surrounds a circumferential array of blades of a gas turbine engine rotor. The shroud ring has a plurality of shroud segments disposed circumferentially one adjacent to another. The circumferentially adjacent shroud segments have confronting sides defining an inter-segment gap therebetween. The inter-segment gaps are sealed by a sealing band mounted to the radially outer surface of the segmented shroud ring so as to extend across the inter-segment gaps around the full circumference of the shroud ring. Impingement jet holes may be defined in the sealing band for cooling the shroud segments.

Abstract: A system and method for particle separation in a gas turbine engine centrifugal impeller bleed air system using a tangential velocity component of the compressor bleed air to centrifuge the particles radially outwardly and convey the particles circumferentially, away from a clean air outlet and towards a particle outlet where the particles are extracted from the bleed air.

Abstract: An active tip clearance control (ATCC) apparatus of an aircraft gas turbine engine is situated within a pressurized core case of the engine. First and second portions of bypass air flow passing through the respective compressed core compartment and the ATCC apparatus, are isolated from one another in order to improve both the ATCC performance and bypass air duct performance.

Abstract: An oil cooled runner, for a rotary seal between an engine case and a shaft rotationally mounted to the case, includes an annular runner ring having a platform with a radially outer seal engagement surface and a radially inner surface, and an oil distributor having a radially inner portion in communication with a source of liquid lubricant and an outer lubricant casting cone with a rim disposed radially inwardly from the inner surface of the platform.

Abstract: An apparatus and method is provided for improving efficiency of a transonic gas turbine engine compressor by bleeding off a shockwave-induced boundary layer from the gas flow passage of the compressor using an array of bleed holes having a downstream edge aligned with a foot of an oblique shock wave which originates on the leading edge of an adjacent transonic rotor blade tip.

Abstract: A compressor comprises a casing having an inner surface surrounding a rotor assembly, the rotor assembly having a plurality of circumferentially spaced radially outwardly extending rotor blades, each blade having leading and trailing edges and a tip, the compressor further comprising at least one plasma actuator for suppressing rotating stall inception of the compressor, the at least one plasma actuator being mounted adjacent to the blade tips.

Abstract: An oil purge system for a mid turbine frame (MTF) of a gas turbine engine has an oil transfer tube surrounded by a heat shield tube. The oil transfer and heat shield tubes extend at their respective inner ends downwardly from an oil port of a bearing housing and terminate at their respective outer ends projecting outwardly from an annular wall of an outer case of the MTF. Oil leaked from the oil port is purged by pressurized air through an annular cavity formed between the oil transfer and heat shield tubes, and is discharged out of the MTF.

Abstract: An apparatus for adjusting a thrust load on a rotor assembly of a gas turbine engine includes an impeller rear cavity defined between a rear face of an impeller of the rotor assembly and a stationary wall spaced axially apart from the rear surface of the impeller. A pressurized air flow with a tangential velocity is introduced into the impeller rear cavity at a tip of the impeller to pressurize the cavity. Means are provided in the cavity for directly interfering with the tangential velocity of the pressurized air flow to affect an average static pressure of the pressurized air flow within the cavity in order to adjust the thrust load on the rotor assembly caused by the average static pressure in the cavity.

Abstract: A method of cooling a shroud ring in a turbine section of gas turbine engine includes identifying a series of alternating high temperature regions and lower temperature regions of a circumferential temperature distribution about the inner surface of the shroud ring, and impinging cooling air on to an outer surface of the shroud ring. More cooling air is impinged onto regions which correspond to the high temperature regions on the shroud ring than to regions corresponding to the lower temperature regions of the shroud ring.