Abstract: A machine includes a liquid lubrication system and a shaft, the shaft being rotatable about a rotation axis, the shaft including a first part, a second part engaged coaxially with the first part, and a journal bearing between the first part and the second part, the first part being rotatable relative to the second part about the rotation axis, a helical feature disposed between the first part and the second part and configured to define a helical pump between the first part and the second part, the pump being hydraulically connected to the liquid lubrication system, the journal bearing being disposed adjacent to the helical feature.

Abstract: A turbofan engine comprising an outer bypass duct, an annular bypass flow path between the outer bypass duct and a core engine, an engine component forming an airflow obstruction adjacent the outer bypass duct, an air cooler having a tube, the tube having at least a sinuous portion extending in the annular bypass flow path, the sinuous portion extending along the outer bypass duct, downstream of the airflow obstruction, the sinuous portion configured for exchanging heat between a fluid circulating in the tube and air circulating in the bypass flow path during operation of the turbofan engine.

Abstract: A fan assembly for a gas turbine engine is described which includes a fan and a leading edge assembly mounted to the fan. The leading edge assembly includes a plurality of leading edge extensions projecting from a central core and circumferentially spaced apart to align with leading edges of the fan blades. The leading edge extensions define cavities between the leading edges and the extensions. The cavities extend radially at least partially within the leading edge extensions, and receive heated pressurized air from the engine in operation. Elongated slots extend radially along a downstream edge of the leading edge extensions, and are defined axially between the downstream edge and the leading edges of the blades. The slots provide fluid flow communication between the cavities and at least pressure surfaces of the fan blades.

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 includes a fan assembly, a compressor assembly, a combustion chamber, a turbine assembly, a bypass duct conveying rearward a bypass airstream driven by the fan assembly when the gas turbine engine is in use, a fairing extending across at least a portion of the bypass duct downstream of the fan assembly, and a heat exchanger having an inlet fluidly connected to the compressor assembly and an outlet fluidly connected to a pneumatic actuator of the gas turbine engine. The fairing has a leading edge and a trailing edge. The heat exchanger is disposed adjacent the trailing edge of the fairing.

Abstract: A machine includes a liquid system and a shaft. The shaft is rotatable about a rotation axis and includes a first part and a second part engaged coaxially with the first part. The first part is rotatable relative to the second part about the rotation axis to define a liquid pump between the first part and the second part. The pump is hydraulically connected to the liquid system. A method of cooling the machine is also provided.

Abstract: An active tip clearance control system of a gas turbine engine and an associated method are disclosed. The system comprises a Coanda effect fluidic device configured to control a flow of clearance control fluid to a turbine section of the gas turbine engine for active tip clearance control.

Abstract: Multi-engine aircraft power plants and associated operating methods are disclosed. An exemplary multi-engine power plant comprises a first turboshaft engine and a second turboshaft engine configured to drive a common load such as a rotary wing of an aircraft; and a heat exchanger in thermal communication with an exhaust gas of the first turboshaft engine and in thermal communication with pre-combustion air of the second turboshaft engine. The heat exchanger is configured to permit heat transfer from the exhaust gas of the first turboshaft engine to the pre-combustion air of the second turboshaft engine.

Abstract: The pump can have a pump body, a main cavity having an inlet and an outlet, a rotor rotatably mounted in the main cavity and configured to pump fluid from the inlet to the outlet as it rotates, a separator cavity disposed adjacent the main cavity and configured to sustain a vortex, a fluid passage fluidly connecting the main cavity to the separator cavity, the fluid passage preserving momentum of fluid from the main cavity to the separator cavity to contribute to the vortex.

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 duct for a gas turbine engine, the duct has a wall defining a flow passage for an airflow, the wall defining a baseline surface, the duct comprising an off-take port for drawing a portion of the airflow out of the duct, the off-take port including a projected portion projecting away from the baseline surface into the flow passage, a conduit opening defined within the projected portion for receiving the portion of the airflow, and an off-take conduit communicating with the conduit opening for directing the portion of the airflow away from the duct, the projected portion having a hump upstream of the conduit opening relative to a direction of the airflow and a scoop downstream of the opening relative to the direction of the airflow.

Abstract: A method of installing a segment of a recuperator within an exhaust duct of a gas turbine engine, including positioning the segment such that its exhaust inlet is in fluid flow communication with the turbine section and its exhaust outlet is adapted to deliver an exhaust flow to atmosphere, engaging its air inlet to a plenum in fluid flow communication with the compressor discharge, and engaging its air outlet to another plenum containing the combustor. One of engaging the air inlet and engaging the air outlet includes forming a rigid connection providing sealed fluid flow communication with the corresponding plenum, and the other of engaging the air inlet and engaging the air outlet includes forming a floating connection providing sealed fluid flow communication with the corresponding plenum. The floating connection allows relative movement of the segment within the exhaust duct.

Abstract: A valve has a housing having an inlet and an outlet. A valve element is biased towards a closed position in which the valve element restricts fluid flow from the inlet to the outlet. The valve element is axially movable by fluid pressure at the inlet towards an open position in which the inlet is in fluid flow communication with the outlet. The valve further has a damping chamber having a metering orifice in fluid communication with the inlet. The damping chamber has an axially facing surface defined by the valve element and having a variable volume varying from a minimum volume when the valve element is in its closed position to a maximum volume when the valve element is in its open position.

Abstract: An aircraft engine that includes an engine core having a core compressor and a core turbine for receiving a core flow, a bypass conduit for receiving a bypass flow, a heat exchanger having at least one first passage and at least one second passage in heat exchange relationship with one another, and a turbocharger having a turbocharger compressor and a turbocharger turbine in driving engagement with each other. An inlet of the turbocharger compressor is in fluid communication with an environment of the aircraft engine. An outlet of the turbocharger compressor is fluidly connected to the bypass conduit through the at least one first passage of the heat exchanger. The core compressor is fluidly connected to an inlet of the turbocharger turbine through the at least one second passage of the heat exchanger such that the turbocharger turbine is located downstream of the heat exchanger relative to a flow circulating in the at least one second passage.

Abstract: A gas turbine fuel system including a main fuel line providing fuel flow from a fuel tank to a combustor, and at least one pump, including an ejector pump, pumping fuel from the fuel tank to the combustor via a fuel metering unit. The fuel metering unit directs a portion of the fuel into a motive flow line which returns a portion of the fuel to the ejector pump. First and second heat exchangers are disposed in serial flow communication within the main fuel line between the pump and the fuel metering unit. The first heat exchanger is a fuel-to-fuel heat exchanger.

Abstract: A cooling system for a gas turbine engine comprises a closed circuit containing a change-phase fluid, at least one heat exchanger configured to receive a first coolant from a first engine system for the change-phase fluid in the closed circuit to absorb heat from the first coolant, whereby the cooling system is configured so that the change-phase fluid at least partially vaporizes when absorbing heat from the at least one heat exchanger. The closed circuit has a cooling exchanger adjacent to an annular wall of a bypass duct, the cooling exchanger configured to be exposed to a flow of cooling air in the bypass duct for the change-phase fluid to release heat to the cooling air and condense at least partially, the cooling exchanger having conduits configured to feed the vaporized change-phase fluid from a heat exchange with the at least one heat exchanger to the cooling exchanger, and to direct condensed change-phase fluid by gravity from the cooling exchanger to the at least one heat exchanger.

Abstract: An active tip clearance control system of a gas turbine engine and an associated method are disclosed. The system comprises a Coanda effect fluidic device configured to control a flow of clearance control fluid to a turbine section of the gas turbine engine for active tip clearance control.

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 method for providing an anti-icing airflow, including extracting a compressed airflow from a core flow path of an engine, heating the compressed airflow, mixing the heated compressed airflow with air extracted from a bypass flow path to create the anti-icing airflow having a higher temperature and pressure than that of the air extracted from the bypass flow path, and circulating the anti-icing airflow away from the bypass flow path. Also, an assembly located at least in part inside a turbofan engine and including a heat exchanger, a flow mixing device having a first inlet in the bypass flow path, a second inlet and an outlet, a first conduit providing fluid communication between the heat exchanger and a compressed air portion of the core flow path, a second conduit providing fluid communication between the heat exchanger and the second inlet, and a third conduit in fluid communication with the outlet.

Abstract: An air-to-air cooler has a heat exchanger integrated to a housing. A first passage extends through the housing for directing a flow of cooling air through the heat exchanger. A second passage extends through the housing for directing a flow of hot air to be cooled through the heat exchanger. The first passage has a cooling air outlet tube disposed downstream of the heat exchanger. The cooling air outlet tube extends across the second passage between the heat exchanger and a hot air inlet of the second passage. The hot air inlet is disposed to cause incoming hot air to flow over the cooling air outlet tube upstream of the heat exchanger. An ejector drives the flow of cooling air through the first passage of the air-to-air cooler. A portion of the hot air flow may be used to drive the ejector.