Abstract: An oil tank for a gas turbine engine is provided. The oil tank includes an oil cavity defined within structural walls of a nacelle of the gas turbine engine, the oil cavity having an oil inlet and an oil outlet. At least one of the structural walls has an interior side facing the oil cavity and an exterior side. The interior side includes a plurality of upstanding protrusions extending into the oil cavity and fully immersed in oil when the gas turbine engine is in use during steady state operation. The exterior side includes a plurality of fins extending therefrom and exposed to an ambient air stream during steady state operation of the gas turbine engine.

Abstract: An oil tank for a gas turbine engine is provided. The oil tank includes an oil cavity defined within structural walls of a nacelle of the gas turbine engine, the oil cavity having an oil inlet and an oil outlet. At least one of the structural walls has an interior side facing the oil cavity and an exterior side. The interior side includes a plurality of upstanding protrusions extending into the oil cavity and fully immersed in oil when the gas turbine engine is in use during steady state operation. The exterior side includes a plurality of fins extending therefrom and exposed to an ambient air stream during steady state operation of the gas turbine engine.

Abstract: Intercooling systems and methods for an aircraft engine are provided. An intercooling system includes: a first inlet configured to receive a first air flow of ambient air into the aircraft engine; a second inlet separate from the first inlet and configured to receive a second air flow of ambient air into the aircraft engine separately from the first air flow of ambient air; and a heat exchanger configured to facilitate heat transfer between at least a portion of the first air flow compressed by a compressor section of the aircraft engine and the second air flow.

Abstract: An oil tank for a gas turbine engine. The oil tank includes an oil cavity defined within structural walls of a nacelle of the gas turbine engine, the oil cavity having an oil inlet and an oil outlet. At least one of the structural walls has an interior side facing the oil cavity and an exterior side. The interior side includes a plurality of upstanding protrusions extending into the oil cavity and fully immersed in oil when the gas turbine engine is in use during steady state operation. The exterior side includes a plurality of fins extending therefrom and exposed to an ambient air stream during steady state operation of the gas turbine engine.

Abstract: Intercooling systems and methods for an aircraft engine are provided. An intercooling system includes: a first inlet configured to receive a first air flow of ambient air into the aircraft engine; a second inlet separate from the first inlet and configured to receive a second air flow of ambient air into the aircraft engine separately from the first air flow of ambient air; and a heat exchanger configured to facilitate heat transfer between at least a portion of the first air flow compressed by a compressor section of the aircraft engine and the second air flow.

Abstract: A gas turbine engine is provided, with a compressor section including a fan driven by an engine shaft about a rotation axis, the engine shaft defining a bore extending axially therethrough from a hot gas inlet to a hot gas outlet, the hot gas inlet located downstream of the compressor section, a nose cone mounted to the fan and defining a cavity therewithin, a first impeller and a second impeller mounted within the cavity, the first impeller having an inlet facing a forward direction of the gas turbine engine, the inlet of the first impeller in fluid flow communication with an air inlet defined in an outer surface of the nose cone, the second impeller having an inlet facing a rearward direction of the gas turbine engine, the inlet of the second impeller being in fluid flow communication with the hot gas outlet of the engine shaft.

Abstract: A gas turbine engine includes a supply air conduit fluidly connected to an inlet of a combustion chamber to convey supply air to the combustion chamber, an exhaust conduit fluidly connected to an exit of the combustion chamber to convey exhaust gases away from the combustion chamber, and a recuperator defining a first flow path and a second flow path therethrough, the second flow path being in heat transfer communication with the first flow path, the first flow path defining part of the supply air conduit, the second flow path defining part of the exhaust conduit. Methods of operating the engine are also provided.

Abstract: A gas turbine engine is provided, with a compressor section including a fan driven by an engine shaft about a rotation axis, the engine shaft defining a bore extending axially therethrough from a hot gas inlet to a hot gas outlet, the hot gas inlet located downstream of the compressor section, a nose cone mounted to the fan and defining a cavity therewithin, a first impeller and a second impeller mounted within the cavity, the first impeller having an inlet facing a forward direction of the gas turbine engine, the inlet of the first impeller in fluid flow communication with an air inlet defined in an outer surface of the nose cone, the second impeller having an inlet facing a rearward direction of the gas turbine engine, the inlet of the second impeller being in fluid flow communication with the hot gas outlet of the engine shaft.

Abstract: A gas turbine engine includes a supply air conduit fluidly connected to an inlet of a combustion chamber to convey supply air to the combustion chamber, an exhaust conduit fluidly connected to an exit of the combustion chamber to convey exhaust gases away from the combustion chamber, and a recuperator defining a first flow path and a second flow path therethrough, the second flow path being in heat transfer communication with the first flow path, the first flow path defining part of the supply air conduit, the second flow path defining part of the exhaust conduit. Methods of operating the engine are also provided.

Abstract: Apparatus and methods for heating pre-combustor air in a gas turbine engine are disclosed. In one embodiment, a gas turbine engine configured for heating the pre-combustor air comprises a compressor for pressurizing air received in the gas turbine engine; an electric heater configured to heat the compressed air; a combustor in which the heated compressed air is received, mixed with fuel and ignited for generating combustion gas; and a turbine for extracting energy from the combustion gas. Joule heating may be used to heat the compressed air upstream of the combustor.

Abstract: The gas turbine engine can have a rotor rotatably mounted to an engine casing, the rotor having compressor blades, and an alternator, the alternator having an armature with a winding forming part of the rotor and a magnetic field generator forming part of the engine casing, with an air gap between the magnetic field generator and the armature, the winding being electrically connected to a resistor embedded in at least one of the compressor blades.

Abstract: A method of applying a nanocrystalline metal coating to a titanium or titanium alloy blade of a gas turbine engine is described. The method includes selecting an intermediate bond coat from the group consisting of nickel, nickel alloy, P, B, Tl and combinations thereof, and applying the intermediate bond coat to at least a portion of the blade. A nanocrystalline metal coating having an average grain size of between 10 nm and 500 nm is then applied to the portion of the blade overtop of the intermediate bond coat.

Abstract: An assembly of a shaft and a rotor disk comprises a shaft configured to rotate at a first angular speed S1 about a shaft rotational axis. A bladed rotor includes a disk adapted to support blades, the disk having a rotor rotational axis, the disk being integrally and monolithically formed with at least one rotor gear, the rotor gear being concentric with the disk about the rotor rotational axis. A gear train includes a shaft gear fixed to the shaft, the gear train having at least one gear meshed with the rotor gear for imparting a rotation to the bladed rotor at angular speed S2, wherein the angular speed S1?the angular speed S2.

Abstract: A fan blade of a gas turbine engine is disclosed which is composed of an airfoil having a leading edge and a trailing edge, and a root with a platform and a blade fixing for engaging a fan hub. The fan blade is composed of a core substrate selected from the group consisting of composites and polymers, and an entirety of the airfoil and the root of the fan blade has a nanocrystalline metal outer layer thereon which forms an outer surface fully enveloping the fan blade. The nanocrystalline metal layer formed of a nanocrystalline metal coating has an average grain size of between 10 nm and 500 nm, and the nanocrystalline metal outer layer forms a structural element of the fan blade.

Abstract: Apparatus and methods for heating pre-combustor air in a gas turbine engine are disclosed. In one embodiment, a gas turbine engine configured for heating the pre-combustor air comprises a compressor for pressurizing air received in the gas turbine engine; an electric heater configured to heat the compressed air; a combustor in which the heated compressed air is received, mixed with fuel and ignited for generating combustion gas; and a turbine for extracting energy from the combustion gas. Joule heating may be used to heat the compressed air upstream of the combustor.

Abstract: A stator airfoil of a gas turbine engine according to one embodiment includes at least two winglets projecting transversely from opposed sides of a stator airfoil, respectively. Each winglet includes a leading edge axially and outwardly extending from one of the opposed sides of the stator airfoil and a trailing edge extending from the stator airfoil to join with the leading edge of the winglet. The winglets therefore provide a wide trailing edge thereof to aerodynamically manage boundary layers and micro-shocks of a working fluid.

Abstract: A rotor assembly having a plurality of scoops disposed in a circumferential array, the scoops extending from an inner surface of the outer wall of the flow path along a radial distance smaller than a radial distance between the inner and outer walls of the flow path. Each of the scoops forms a closed channel from an inlet to an outlet with the inlet and outlet being axially spaced from one another, the outlet being upstream of and adjacent the annular blade path. A gas turbine engine and method of reducing tip vortices in a rotor assembly are also discussed.

Abstract: A rotor assembly having a wear member secured to an inner surface of the outer wall of the flow path. The wear member is made of material abradable by the blades. The wear member is located upstream of the blades. A downstream end of the wear member is abradably shaped by the blades upon rotation. An inner surface of the wear member is directed radially inwardly along a direction of flow in the flow path for deflecting a boundary layer of the flow into the annular blade path. A gas turbine engine and a method reducing tip vortices in a rotor assembly are also discussed.

Abstract: A fan blade of a gas turbine engine, and a method of producing same, is disclosed which is composed of a core substrate and a nanocrystalline metal coating provided on at least a portion of the airfoil of the fan blade. The method includes the steps of providing a fan blade core having an airfoil and then applying a nanocrystalline metal coating over at least a portion of the fan blade core.

Abstract: A stator airfoil of a gas turbine engine according to one embodiment includes at least two winglets projecting transversely from opposed sides of a stator airfoil, respectively. Each winglet includes a leading edge axially and outwardly extending from one of the opposed sides of the stator airfoil and a trailing edge extending from the stator airfoil to join with the leading edge of the winglet. The winglets therefore provide a wide trailing edge thereof to aerodynamically manage boundary layers and micro-shocks of a working fluid.