Abstract: A recuperator inserted in the exhaust duct of a gas turbine engine includes a casing surrounding a core having spiral cross channels. Inlet and outlet openings are defined in the casing for the passage of hot exhaust gases through the exhaust channels in the core. Feeder members extend radially across the outlet opening for passing the pre-combustion stage air through the air channels of the core, and header members extend radially across the inlet opening of the casing for receiving and redirecting air from the air channels in the core towards the combustor section. The feeder and header members each have a tapered configuration from the casing to the axial center of the casing so as to maintain a relatively constant pressure over the radial extent of the respective feeders and headers.

Abstract: A fan for a turbofan gas turbine engine, the fan comprising a rotor hub and a plurality of radially extending fan blades integral with the hub to form an integrally bladed rotor. Each fan blade defines a leading edge. A hub radius (RHUB) is the radius of the leading edge at the hub relative to a centerline of the fan. A tip radius (RTIP) is the radius of the leading edge at a tip of the fan blade relative to the centerline of the fan. The ratio of the hub radius to the tip radius (RHUB/RTIP) is at least less than 0.29. In a particular embodiment, this ratio is between 0.25 and 0.29. In another particular embodiment, this ratio is less than or equal to 0.25.

Abstract: A combustor assembly includes a hot skin of a combustion chamber wall having an inner face exposed to the combustion chamber and an opposite outer face, a receiving skin having a securing portion affixed to the hot skin outer face in an air-tight manner and a receiving flange, extending from the securing portion, that is offset from the hot skin outer face to form a female recess, a cold skin having a cold wall portion spaced from the hot skin and forming a cooling cavity therebetween, a securing portion extending from a first end of the cold wall portion affixed to the hot skin outer face in an air-tight manner and a male flange extending from a second end of the cold wall portion opposite the first end, the male flange snugly received in the female recess and forming a sliding engagement therebetween.

Abstract: A system and method for controlling the operation of a gas turbine engine supplying power to an aircraft. The engine is controlled according to a reading of an amount of power drawn from the supplied power. The reading is fed directly to a control system, which issues commands for controlling engine parameters comprising an acceleration reference signal, load shedding, variable geometry positioning, and fuel flow. The control system may further issue commands for controlling the amount of power drawn. The control system may further use the reading to monitor the engine's condition.

Abstract: A multi spool gas turbine engine with a differential having a selectively rotatable member which rotational speed determines a variable ratio between rotational speeds of driven and driving members of the differential. The driven member is engaged to the first spool and a rotatable shaft independent of the other spools (e.g. connected to a compressor rotor) is engaged to the driving member. First and second power transfer devices are engaged to the first spool and the selectively rotatable member, respectively. A circuit interconnects the power transfer devices and allows a power transfer therebetween, and a control unit controls the power being transferred between the power transfer devices. Power can thus be transferred between the first spool and the selectively rotatable member to change the speed ratio between the first spool and the rotatable shaft.

Abstract: There is described a method for controlling an engine and a system architecture for an engine. The system architecture comprises a first electric machine having a single rotor dual stator configuration for operating as a starter-generator for the engine; a second electric machine having a single rotor dual stator configuration for operating as a motor; a dual channel motor drive unit coupled to the second electric machine; a dual channel power control unit coupled to the first electric machine and the motor drive unit; a dual channel full authority digital engine control (FADEC) coupled to the dual channel power control unit and the dual channel motor drive unit; and at least two accessories coupled to the second electric machine and driven by motive power from the single rotor of the second electric machine.

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 slinger combustor has an annular combustor shell defining a combustion chamber having a radially inner fuel inlet for receiving a spray of fuel centrifuged by a fuel slinger. The combustion chamber has a fuel atomization zone extending radially outwardly from the fuel inlet and merging into a radially outwardly flaring expansion zone leading to a combustion zone. A plurality of nozzle air inlets are defined in the fuel atomization zone of the combustor shell. The nozzle air inlets have a nozzle axis intersecting the stream of fuel and a tangential component in a direction of rotation of the fuel slinger. A plurality of dilution holes are defined in the combustor shell and have a dilution axis intersecting the combustion zone. The dilution axis of at least some of the dilution holes has a tangential component opposite to the direction of rotation of the fuel slinger.

Abstract: A gas turbine engine comprises an annular combustor chamber formed between an inner liner and an outer liner. An annular upstream zone is adapted to receive fuel and air from an annular nozzle. An annular mixing zone is located downstream of the upstream zone. The mixing zone has a reduced radial height relative a downstream combustion zone of the combustion chamber, the mixing zone defined by straight wall sections.

Abstract: A rotary engine with an outer body having an insert located in the peripheral offset from the rotor cavity such that a portion of the peripheral wall extends between the insert and the cavity. The insert has a pilot subchamber defined therein and the portion of the peripheral wall has at least one opening defined therethrough in communication with the at least one outlet opening of the insert and with the cavity. A method of combusting fuel into a rotary engine is also discussed.

Abstract: An impeller for increasing the pressure of a fluid circulating in an annular fluid path, the impeller comprising: a plurality of centrifugal compressor vanes circumferentially interspaced around the axis of the annular fluid path, the plurality of compressor vanes extending from an axially-oriented inlet to a radially-oriented outlet, and each having an inner edge and a free edge, the free edge of the plurality of compressor vanes coinciding with an outer limit of the annular fluid path, and a hub having a solid-of-revolution shape centered around an axis, the hub having an outer hub surface forming an inner limit to the annular fluid path and to which the inner edge of the plurality of centrifugal vanes is secured, the outer hub surface having a portion which leans forward, forming an axial recess therein.

Abstract: A gas turbine engine includes an annular plenum defined with an outer skin and a perforated inner skin for receiving selective air flow to impinge a support case which supports shrouds of the rotor assemblies of the engine therein for active tip clearance control of the rotor assemblies. In one embodiment a bobbin-type transfer tube for supplying cooling air into the plenum, is provided between an outer case of the engine an the plenum such that the thermally induced relative movement of the outer case and the plenum is permitted.

Abstract: A rotor blade for a gas turbine engine includes a leading edge tip rib projecting outwardly from an airfoil of the blade at a tip region thereof. The tip rib continuously surrounds a leading edge of the airfoil and extends rearwardly from the leading edge along respective pressure and suction side surfaces to thereby alter the blade tip leakage vortex structure and strength, resulting in a stage efficiency benefit.

Abstract: A turbine blade for a gas turbine engine with an airfoil portion defined by a perimeter wall surrounding at least one enclosure, the perimeter wall having a plurality of cooling holes defined therethrough and providing fluid communication between the at least one enclosure and a gaspath of the gas turbine engine. The plurality of cooling holes includes at least one row of holes selected from the group consisting of a first row, a second row, a third row and a fourth row, with the first, second, third and fourth rows of holes respectively including the holes numbered PA-1 to PA-10, PB-1 to PB-3, HA-1 to HA-9, and SA-1 to SA-8 located such that a central axis thereof extends through the respective point 1 and point 2 having a nominal location in accordance with the X, Y, Z Cartesian coordinate values set forth in Table 3.

Abstract: A turbine blade for a gas turbine engine with an airfoil portion defined by a perimeter wall surrounding at least one enclosure, the perimeter wall having a plurality of cooling holes defined therethrough and providing fluid communication between the at least one enclosure and a gaspath of the gas turbine engine. The plurality of cooling holes includes at least one row of holes selected from the group consisting of a first row, a second row, a third row and a fourth row, with the first, second, third and fourth rows of holes respectively including the holes numbered PA-1 to PA-10, PB-1 to PB-3, HA-1 to HA-9, and SA-1 to SA-8 located such that a central axis thereof extends through the respective point 1 and point 2 having a nominal location in accordance with the X, Y, Z Cartesian coordinate values set forth in Table 3.

Abstract: A gas turbine engine including a compressor rotor and a turbine rotor connected by a compressor shaft portion connected to the compressor rotor and a turbine shaft portion connected to the turbine rotor. The compressor shaft portion and the turbine shaft portion are connected axially together by a shaft coupling, between the compressor rotor and the turbine rotor, and at least a bearing rotatably coupled to the compressor shaft portion adjacent the shaft coupling. The compressor shaft and/or the turbine shaft are provided with openings permitting cooling air to enter air passages in the area of the shaft coupling and surrounding the end of the turbine shaft portion, in order to dissipate heat originating at the turbine rotor and thus reducing the thermal stresses at the bearing.

Abstract: A method of designing a fuel nozzle of a gas turbine engine to reduce fretting thereof during use, including establishing an initial nozzle design, determining a first natural frequency of that design and a running frequency range of the gas turbine engine, and increasing a first transverse dimension of the stem member of the nozzle across a length of a portion thereof adjacent the inlet end until the first natural frequency of the nozzle is outside the running range, while a second transverse dimension of the portion remains at least substantially unchanged across the length thereof.

Abstract: A gas turbine engine case having a working fluid flow, includes inner and outer case portions defining an annular duct for directing the working fluid flow, and a plurality of struts positioned within the annular duct and extending between the inner and outer case portions. The struts are welded to the inner and outer case portions with a first weld along a peripheral line of the respective struts and with second weld, of fillet type, in selected locations for additionally connecting a portion of each strut to the respective inner and outer case portions.

Abstract: The method is used for making an annular gas turbine engine case from a preform. The method comprises comprising flowforming at least one section of the preform, and then outwardly bending at least one portion of the perform.

Abstract: A modular fuel nozzle tip for a gas turbine engine includes a body defining one or more fuel conveying passages extending therethrough, an annular cap having a radially inner shoulder surface interfacing with the peripheral end surface of the body to define a plurality of air channels extending through the head portion of the modular fuel nozzle tip. At least two fasteners fasten the annular cap to the body.