Abstract: A blade outer air seal (BOAS) of a gas turbine engine has a segmented support ring to support a segmented turbine shroud. The support ring has a cooling air distribution system which includes a plurality of inlet cavities extending axially and inwardly to communicate with an inner cooling air passage within the respective support segments. The inlet cavities each are formed with two recesses defined in respective adjacent two support segments.

Abstract: A blade outer air seal (BOAS) of a gas turbine engine has a segmented support ring to support a segmented turbine shroud. The support ring has a cooling air distribution system which includes a plurality of inlet cavities extending axially and inwardly to communicate with an inner cooling air passage within the respective support segments. The inlet cavities each are formed with two recesses defined in respective adjacent two support segments.

Abstract: An arrangement for sealing a turbine shroud gas path duct interface of a turbine engine comprises a static shroud surrounding a rotatable airfoil array and an annular duct downstream of the shroud with respect to a gas flow passing through the gas path. The shroud and the duct define a portion of the gas path for directing the gas flow, having an axially extending interface gap between the shroud and duct. An annular seal in use engages both the shroud and the duct, thereby sealing the annular gap.

Abstract: An airfoil for a gas turbine engine including a tip extension disposed at the tip of the airfoil body. The tip extension extends from the suction side surface and/or the pressure side surface and defines a tip thickness that is larger than a true thickness of the airfoil body. The true thickness is defined within a plane perpendicular to a root axis and extending transversely to the airfoil chord around a midpoint thereof. The tip extension includes a side transitional surface forming a curve extending tangentially from the side surface and/or the pressure side surface. The tip thickness increases over a radial dimension in the plane that is at least 2 times the true thickness.

Abstract: A gas turbine engine has a compressor assembly and a turbine assembly rotationally mounted on a shaft, the turbine assembly being driven by hot gases discharged from a combustion chamber disposed between the compressor and turbine assemblies, the compressor having a centrifugal impeller for pressurizing and impelling air into the combustion chamber. The engine also includes an impeller shroud covering the bladed portion of the centrifugal impeller, the impeller shroud having a support bracket having a thin and curved load-isolating profile for supporting a strut that secures the impeller shroud to a case of the engine.

Abstract: There is provided a system and a method for controlling a tip clearance between a turbine casing and turbine blade tips of an aircraft engine. At least one operational parameter of the aircraft engine is obtained. Based on the at least one operational parameter, a current value of the tip clearance and a target value of the tip clearance are determined. A limiting factor to be applied to the target value of the tip clearance is computed. The limiting factor is applied to the target value of the tip clearance to obtain a tip clearance demand for the aircraft engine. A tip clearance control apparatus of the aircraft engine is controlled based on a difference between the current value of the tip clearance and the tip clearance demand.

Abstract: A method of manufacturing a turbine shroud segment for a gas turbine engine comprises: metal injection molding (MIM) a shroud segment body with a groove defined in a first lateral side thereof and with a flow restrictor projecting integrally from an opposite second lateral side thereof. The groove is oversized relative to the flow restrictor to provide for a clearance fit between the flow restrictor and the groove of adjacent turbine shroud segments when assembled together in a ring formation. The shroud segment body with the integrated flow restrictor are then subjected to debinding and sintering operations.

Abstract: A turbine shroud segment has a body having a radially outer surface and a radially inner surface extending axially between a leading edge and a trailing edge and circumferentially between a first and a second lateral edge. A first serpentine channel is disposed axially along the first lateral edge. A second serpentine channel is disposed axially along the second lateral edge. The first and second serpentine channels each define a tortuous path including axially extending passages between a front inlet proximate the leading edge and a rear outlet at the trailing edge of the body.

Abstract: A turbine shroud segment has a body having a radially outer surface and a radially inner surface extending axially between a leading edge and a trailing edge and circumferentially between a first and a second lateral edge. A first serpentine channel is disposed axially along the first lateral edge. A second serpentine channel is disposed axially along the second lateral edge. The first and second serpentine channels each define a tortuous path including axially extending passages between a front inlet proximate the leading edge and a rear outlet at the trailing edge of the body.

Abstract: A cooled turbine shroud segment for a gas turbine engine, having an axially extending shroud ring segment with an inner surface, an outer surface, an upstream flange and a downstream flange. The flanges mount the shroud ring within an engine casing. A perforated cooling air impingement plate is disposed on the outer surface of the shroud ring between the upstream flange and the downstream flange, with an impingement plenum defined between the impingement plate and the outer surface. Axially extending cooling bores in the ring segment extend between the impingement plenum and an outlet. A trough adjacent the outlet directs cooling air from the outlet towards a downstream stator vane to cool the stator vane.

Abstract: A blade outer air seal (BOAS) assembly includes a static turbine shroud formed by BOAS segments and a support ring formed by BOAS support segments. Each BOAS support segment supports one or more BOAS segments. The BOAS assembly further includes an anti-rotation apparatus for restricting relative circumferential movement between the turbine shroud and the support ring. The anti-rotation apparatus includes a stopper provided at least in one of the BOAS support segments and a cast anti-rotation tab integrated with at least one of the BOAS segments supported on that at least one BOAS support segment. The stopper and cast anti-rotation tab circumferentially abut each other.

Abstract: A multi-stage axial compressor with an inner wall including a step portion for each of the compressor stages. Each step portion is defined along a respective stage. Each step portion may extend over at least a majority of an axial length of the stage. Each step portion may optionally include a point aligned with a maximum thickness of the airfoil portions of the rotor blades and a point aligned with a maximum thickness of the stator vanes. Adjacent step portions are connected by a transition portion converging toward a central axis of the compressor from the upstream step to the downstream step. Each transition portion has a steeper slope than that of the adjacent step portions. A method of directing flow through a multi-stage axial flow compressor is also discussed.

Abstract: A turbine shroud segment for a gas turbine engine having an annular gas path extending about an engine axis. The engine has a turbine rotor mounted for rotation about the axis and having a plurality of blades extending into the gas path. The turbine shroud segment includes a body extending axially between a leading edge and a trailing edge and circumferentially between a first and second lateral edges. The body has a radially outer surface and a radially inner surface. The radially outer surface includes a textured surface exposed to a cooling flow. The radially inner surface defines an outer flow boundary surface of the gas path next to a tip of one of the blades. A cooling flow passageway is defined in the body and extends axially between one or more cooling inlets receiving the cooling flow from the textured surface and one or more cooling outlets.

Abstract: An impeller shroud assembly for a gas turbine engine includes an annular impeller shroud disposed about an axial centerline. The impeller shroud includes a shroud inducer portion and a shroud exducer portion disposed radially outward of the shroud inducer portion and extending to an outer radial end of the impeller shroud. The shroud inducer portion and the shroud exducer portion defining an impeller-facing surface of the impeller shroud. The impeller shroud has a pivot point defined between the shroud inducer portion and the shroud exducer portion. The impeller shroud assembly further includes a clearance control device connected to the shroud exducer portion of the impeller shroud proximate the outer radial end. The clearance control device is configured to pivot the shroud exducer portion of the impeller shroud about the pivot point between a first axial position and a second axial position.

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.

Abstract: There is provided a method of assembling a gas turbine engine using a concentricity ring to compensate for assembly tolerances. The blade tips of the gas turbine during turbine rotation define a tip surface of rotation concentric the shaft axis. Due to cumulative tolerances in part manufacture and assembly, the shaft axis is invariably radially eccentric the engine axis at the axial position of the turbine an assembly eccentricity within the range between zero and a predetermined allowable assembly tolerance.

Abstract: A rotor containment structure for gas turbine engine comprises an inner containment layer having a single integral body defining an annular structure about the rotor, and having a support on the inner surface of the inner containment layer for at least one shroud segment. An outer containment layer provides containment strength to contain blade fragments and defining an annular structure about the inner containment layer. Air passage through the outer containment layer for air to pass from an exterior of the outer containment layer to an interior of the outer containment layer; and the inner containment layer being connected at a first end to the outer containment layer with a gap defined between the inner surface of the outer containment layer and the outer surface of the inner containment layer, the gap being in fluid communication with the air passage such that air flows through the gap, beyond a free second end of the inner containment layer.