Abstract: A gas turbine engine has a compressor section, a combustor, and a turbine section. An associated fluid is to be cooled and an associated fluid is to be heated. A transcritical vapor cycle heats the fluid to be heated, and cools the fluid to be cooled. The transcritical vapor cycle includes a gas cooler in which the fluid to be heated is heated by a refrigerant in the transcritical vapor cycle. An evaporator heat exchanger at which the fluid to be cooled is cooled by the refrigerant in the transcritical vapor cycle. A compressor upstream of the gas cooler compresses the refrigerant to a pressure above a critical point for the refrigerant. An expansion device expands the refrigerant downstream of the gas cooler, with the evaporator heat exchanger being downstream of the expansion device, and such that the refrigerant passing through the gas cooler to heat the fluid to be heated is generally above the critical point.

Abstract: An oil supply system includes a first oil receptacle collecting oil from a transmission and a second oil receptacle collecting oil from the rest of a drive system using gravity. Oil supply pump(s) supply oil from the oil receptacle(s) to the different consumers. A vacuum pump generates a negative pressure in the first oil receptacle and in the transmission casing connected to the first oil receptacle. A gas check valve prevents gas from flowing between the oil receptacles when a pressure differential is applied to the oil receptacles by the vacuum pump. An oil check valve prevents oil from flowing between the oil receptacles when the pressure differential is applied. An oil regulating valve may control the oil flow between the first and second oil receptacles. The oil supply system provides a simpler configuration without scavenging pump(s).

Abstract: A shaft bearing assembly having a shaft supported in a bearing housing is described. The shaft bearing assembly includes a pressure reduction device for generating an underpressure inside the bearing housing. The pressure reduction device is operated by employing an incompressible fluid. Further, a method of reducing a pressure inside a bearing housing supporting a shaft is described. The method includes using an incompressible fluid for operating a pressure reduction device for generating an underpressure inside the bearing housing.

Abstract: A fuel delivery system for a gas turbine engine includes a fuel source; a draw pump downstream of the fuel source for generating a liquid fuel flow from the fuel source; a main fuel pump downstream of the draw pump; and a fuel oxygen reduction unit downstream of the draw pump and upstream of the main fuel pump.

Abstract: A fuel supply circuit including a supply duct in which a first flow (Fl) is able to circulate, at least one supply pump for circulating the fuel from a tank to a metering unit, and a recirculation duct for a second flow upstream of the pump, wherein the ducts (20, 60) discharge in different directions upstream of the pump; the circuit includes a dispensing device including an internal flow duct for the first flow (Fl), an external flow channel for the second flow and at least one passage orifice for the second flow, which communicates fluidically with the channel; and the at least one orifice (810) and the duct are coaxial and respectively discharge upstream of the pump.

Abstract: An insert for supplying a fluid to splines of a drive shaft, the insert comprising an insert wall extending between a first end and a second end of the insert, a chamber surrounding the insert wall for storing a fluid, a piston having a surface configured to be exposed to the fluid, the piston configured to move between a first position and a second position within the chamber, and the piston biased toward the first position, and wherein an increase in supply of the fluid in the chamber causes the piston to move toward the second position and a decrease in supply of the fluid in the chamber causes the piston to move toward the first position.

Abstract: An apparatus is provided for a gas turbine engine. This apparatus includes a vane array and a heat exchanger integrated with the vane array. The vane array includes an inner platform, an outer platform and a plurality of vanes. The inner platform extends circumferentially about a centerline and forms an inner peripheral boundary of a flowpath through the vane array. The outer platform extends circumferentially about the centerline and forms an outer peripheral boundary of the flowpath through the vane array. The vanes extend across the flowpath between the inner platform and the outer platform. The heat exchanger includes a passage following a tortuous trajectory along a first wall of the vane array.

Abstract: A multi-engine aircraft includes first and second gas turbine engines for providing motive power to the aircraft, each of the first and second engines comprising an air system, an air pressure line extending between and fluidly connecting the air systems of the first and second engines, and a pressure wave damper communicating with the air pressure line extending between the first and second engines.

Abstract: A gas turbine engine according to one aspect of the present invention includes: an oil tank storing lubricating oil; and a cylindrical external case accommodating a compressor, a combustor, and a turbine. The oil tank is arranged along an outer peripheral surface of the external case so as to surround the external case.

Abstract: A turbofan aircraft propulsion assembly includes a retractable heat exchanger. The heat exchanger can be deployed in a secondary flow path of the propulsion assembly so as to cool a fluid circulating in a circuit of a transfer module of the heat exchanger using a secondary flow circulating in the secondary flow path.

Abstract: The present invention provides a propulsion apparatus that generates a propulsion force of a flying body, comprising: a propulsion rotor; a motor configured to pivotally support and rotate the propulsion rotor; power generation unit configured to generate power for driving the motor; and a housing configured to store the power generation unit, wherein the housing is arranged outside an airframe of the flying body, and the motor is connected to the housing.

Abstract: A gas turbine engine assembly includes a gas turbine engine with a combustion section, a fuel delivery system, and a thermal energy management system. The fuel delivery assembly provides a fuel to the combustion section of the gas turbine engine. The thermal energy management system includes a thermal transport bus, a heat source heat exchanger, and a heat sink heat exchanger. The thermal transport bus has a portion of the fuel configured to flow therethrough. The fuel is disposed as a heat exchange fluid of the thermal energy management system. The heat source heat exchanger is in thermal communication with the flow of fuel through the transport bus. The heat sink heat exchanger is in thermal communication with the flow of fuel through the transport bus.

Abstract: An oil supply device of an aircraft gas turbine includes: a lubrication extraction pipe including a first end and a second end, the first end communicating with a compressor of the gas turbine, an ejection port being provided at the second end and directed to a lubricated member; an oil tank configured to store oil; an oil pipe including a first end and a second end, the first end communicating with the oil tank, the second end communicating with the lubrication extraction pipe; and an electric pump interposed on a portion of the oil pipe and configured to suck the oil from the oil tank and supply the oil to an inside of the lubrication extraction pipe.

Abstract: A fan drive gear system for a gas turbine engine includes a gear system that provides a speed reduction between a fan drive turbine and a fan and a mount flexibly supporting portions of the gear system. A lubrication system supporting the fan drive gear system provides lubricant to the gear system and removes thermal energy produced by the gear system. The lubrication system includes a capacity for removing thermal energy equal to less than about 2% of power input into the gear system.

Abstract: In accordance with at least one aspect of this disclosure, there is provided a system for an aircraft engine. In embodiments, the system includes an accessory box and a fuel accessory located in an interior space within the accessory box, where a vent is defined through a wall of the accessory box. In embodiments, the vent includes a plurality of holes or slots in an outer wall of the accessory box for passage of gaseous fuel from the interior space. In embodiments, the vent is configured for passive ventilation of the interior space.

Abstract: The present invention relates to a bypass air/fluid heat exchanger (2) for a turbofan engine. According to the invention, this exchanger (2) comprises: —an annular outer shroud (3) with two walls, an inner wall (32) and an outer wall (31), —an annular inner shroud (4) concentric with the outer shroud (3), —a series of OGV guide vanes (5) which connect said outer shroud to said inner shroud, —and a circulation circuit (6) for circulating said fluid, the two shrouds delimiting a bypass air flow path, the fluid circulation circuit (6) is formed in the body of the outer shroud (3) and in the body of at least one of the OGV guide vanes (5), this circulation circuit (6) opening at the two respective ends thereof into an inlet opening (34) and into an outlet opening (35), formed through said outer wall (31) of the outer shroud, and the two shrouds (3, 4), the OGV guide vanes (5) and the circulation circuit (6) of said fluid are integral.

Abstract: An insert for supplying a fluid within a drive shaft, the insert extending along an axis of rotation and comprising an insert wall having a rigid inner insert wall portion and an elastically deformable outer insert wall portion a reservoir defined by the insert wall for storing a fluid, a nozzle positioned at the first end of the insert wall, and wherein the elastically deformable outer insert wall portion is configured to move between an expanded state, when the fluid is supplied to the reservoir, and an unexpanded state, when rotation of the insert and supply of fluid to the reservoir are ceased, and movement of the elastically deformable outer insert wall portion to the unexpanded state forces the fluid to be discharged through the nozzle.

Abstract: A gas turbine engine includes: a casing that accommodates a compressor and the like; bearings; a main lubricator including an oil mist generator that generates oil mist by mixing oil with compressed air extracted from the compressor and a first supply passage through which the oil mist is guided to the bearings; and a starting lubricator including a second supply passage through which a gas flowing out from a gas source is guided to a connection portion of the first supply passage, the connection portion being connected to the second supply passage, and an opener that starts supply of the gas from the gas source. The main lubricator supplies the oil mist to the bearings through the first supply passage by the pressure of the compressed air extracted from the compressor. When the opener starts the supply of the gas, the starting lubricator supplies the oil mist to the bearings by the pressure of the gas flowing out from the gas source.

Abstract: An aircraft propulsion assembly includes a turbine engine surrounded by a nacelle with an annular air-intake lip extending around the turbine engine by two annular walls, inner and outer, respectively, intended for being swept across by air flows at least when the aircraft is in flight. The inner and outer walls each includes or supports at least one network of pipes forming heat exchangers. The inner wall pipe network having liquid outlet connected with a liquid intake of the outer wall pipe network. The propulsion assembly further includes means for circulating the liquid, connected to at least one liquid intake of the network of pipes of the inner wall.

Abstract: A turbofan engine is provided. The turbofan engine includes a fan comprising a plurality of rotatable fan blades, each fan blade defining a fan tip speed; a turbomachine operably coupled to the fan for driving the fan, the turbomachine comprising a compressor section, a combustion section, and a turbine section in serial flow order and together defining a core air flowpath; and a gear box, wherein the turbomachine is operably coupled to the fan through the gear box, wherein a gear ratio of the gear box is greater than or equal to 1.2 and less than or equal to 3.0; wherein during operation of the turbofan engine at a rated speed the fan tip speed is greater than or equal to 1000 feet per second. In exemplary embodiments, during operation of the turbofan engine at the rated speed the fan pressure ratio is less than or equal to about 1.5.

Abstract: The present invention relates to a method for quantitative measurement of catechol estrogen bound protein in blood sample. By detecting adduction levels of binding sites of the catechol estrogen on the protein in blood sample, the catechol estrogen bound protein in the blood sample can be detected quantitatively and a limit of quantitation can be decreased.

Abstract: A gas turbine engine includes a fan rotor driven by a fan drive turbine about an axis through a gear reduction to reduce a speed of the fan rotor relative to a speed of the fan drive turbine. A fan case surrounds the fan rotor, and a core engine with a compressor section, including a low pressure compressor. The fan rotor delivers air into a bypass duct defined between the fan case and the core engine. A rigid connection is between the fan case and the core engine including a plurality of radial struts rigidly connected to the fan case, and to the core engine. A plurality of non-structural fan exit guide vanes and the non-structural fan exit guide vanes are provided with an acoustic feature to reduce noise. The non-structural fan exit guide vanes are rigidly mounted to at least one of the fan case and the core engine.

Abstract: An oil supply system and a method for operating the same to provide oil to a gas turbine engine in a variety of harsh operating conditions is provided. The oil supply system includes a main oil tank and an auxiliary oil tank which share oil through a tank sharing valve that may be closed if a depressurization event occurs in the main oil tank. The oil supply system further includes an auxiliary supply conduit and an auxiliary oil pump for providing oil to the gas turbine engine in the event of main oil tank depressurization or in negative gravity conditions where the oil within the auxiliary oil tank rises to the top of the tank and uncovers the oil pump supply.

Abstract: An oil system of a gas turbine engine, has first and second oil circuits. The oil circuits include. Respectively, first and second oil reservoirs, first and second oil consumers of the engine, and first and second heat exchangers for temperature control. The first oil consumer is impinged with oil from the first oil reservoir. The second oil consumer is impinged with oil from the second oil reservoir. The first oil consumer is connected to the first oil reservoir, and the second oil consumer is connected to the second oil reservoir. The operating temperature of oil in the first oil circuit is lower than in the second oil circuit. The first oil reservoir is connected to the second oil reservoir. Oil from each oil reservoir can be guided into the other oil reservoir via the connection.

Abstract: A mid-turbine frame (MTF) assembly having: an outer case circumferentially extending around a central axis; an outer ring secured to the outer case and disposed radially inwardly of the outer case relative to the central axis; an inner case structurally connected to the outer case and disposed radially inwardly of the outer ring relative to the central axis; a main plenum circumferentially extending around the central axis and located between the outer case and the outer ring, the main plenum having an inlet fluidly connectable to a source of cooling air, a first outlet fluidly connected to a secondary plenum between the main plenum and the inner case, a second outlet configured to be fluidly connected to a rotor cavity of the low-pressure turbine, and a third outlet configured to be fluidly connected to a plenum surrounding a containment ring of the low-pressure turbine.

Abstract: A lubrication system for an attritable engine includes a bearing chamber, a fluid filtering inlet configured to receive a fluid, and a fluid filtering outlet located downstream of the fluid filtering inlet and configured to deliver the fluid to the bearing chamber. The lubrication system also includes a lattice, integral and conformal with the attritable engine, configured to filter the fluid, and located between the fluid filtering inlet and the fluid filtering outlet. The lubrication system also includes a metering port, configured to meter the fluid and located downstream of the lattice and upstream of the fluid filtering outlet.

Abstract: An oil system, has: a pump driving an oil flow in an oil conduit, the pump having an outlet pump pressure; a heat exchanger providing heat exchange between the oil flow and one or more fluid; a component downstream of the heat exchanger, the component having a maximum oil pressure requirement and a minimum oil pressure requirement; and a flow restrictor in fluid flow communication with the oil conduit, the flow restrictor having an orifice sized to provide a restrictor pressure differential across the flow restrictor, the restrictor pressure differential being equal to at least the outlet pump pressure minus pressure differentials through the heat exchanger and the oil conduit from an outlet of the pump to the component minus the maximum oil pressure requirement, and at most the outlet pump pressure minus the pressure differentials through the heat exchanger and the oil conduit minus the minimum oil pressure requirement.

Abstract: An assembly is provided for an aircraft propulsion system. This assembly includes a gas turbine engine and a vapor absorption refrigeration system. The gas turbine engine includes a turbine section. The vapor absorption refrigeration system is configured to be driven by waste heat energy received from the turbine section. The vapor absorption refrigeration system includes a condenser.

Abstract: An oil scavenge system for a gas turbine engine comprising an oil tank and at least one bearing chamber. The oil scavenge system comprises at least one primary scavenge pump, a manifold, a secondary scavenge pump, a deaerator and a filter unit. The at least one primary scavenge pump is configured to pump oil from the at least one bearing chamber to the manifold whilst raising the pressure of the oil from a starting pressure to a first pressure elevated with respect to the starting pressure. The manifold is pressurised to substantially maintain the oil at said first pressure. The secondary scavenge pump is configured to pump oil from the manifold at the first pressure and to raise the pressure of the oil to a second pressure elevated with respect to the first pressure before pumping the oil to the deaerator and through the filter unit to the oil tank.

Abstract: A gas turbine engine includes a buffer system that communicates a buffer supply air to a portion of the gas turbine engine. The buffer system includes a first bleed air supply having a first pressure, a second bleed air supply having a second pressure that is greater than the first pressure, and a valve that selects between the first bleed air supply and the second bleed air supply to communicate the buffer supply air to the portion of the gas turbine engine.

Abstract: An oil system for a gas turbine engine and a method of supplying oil to the system. The oil system includes a main oil tank connected by oil lines with a supplementary oil storage tank, which has an actuator, and that are connected to one oil pump for supplying oil to the gas turbine engine. The supplementary oil storage tank is equal in size or larger than a steady state oil gulp of the system. The method includes supplying oil from a main oil tank through a pipe line using an oil pump, detecting the oil level in the oil system and determining if additional oil is required or requires removing using a sensor and an electronic controller, and transmitting a signal to an actuator to supply or remove oil to and from the pipe lines in the oil system from or into a supplementary oil storage tank.

Abstract: A turbine engine strut stage extends through a gaspath upstream of a guide vane stage. A carbon seal system seals a bearing compartment and has: a carbon seal mounted to the case and a seal runner on the spool; and a seal carrier carrying the carbon seal. The engine passes buffer air along a buffer air supply path internally through one or more first struts of the stage of struts. The engine drains oil along an oil drain path internally through one or more second struts of the stage of struts.

Abstract: A local thermal energy consumer assembly and a local thermal energy generator assembly to be connected to a thermal energy circuit comprising a hot and a cold conduit. The local thermal energy consumer assembly is connected via a flow controller to the hot conduit. The local thermal energy generator assembly is connected via a flow controller to the cold conduit. The flow controller is selectively set in pumping mode or a flowing mode based on a local pressure difference between heat transfer liquid of the hot and cold conduits.

Abstract: A thermal management system for a gas turbine engine includes a heat exchanger including a first coolant passage for a first coolant medium and a second coolant passage for a second coolant medium that is different than the first coolant medium. A first hot flow passage is in thermal communication with the first coolant passage. A second hot flow passage is in thermal communication with the second coolant passage all within a common housing. A first valve controls a flow of a hot medium into at least one of the first hot flow passage or the second hot flow passage. A controller configured to operate the first valve to direct the flow of hot medium into one of the first hot flow passage and the second hot flow passage for transferring thermal energy from the flow of hot medium into one of the first coolant medium and the second coolant medium.

Abstract: A lubricated enclosure for an aircraft turbine engine, including a drained roller bearing provided with drainage orifices, as well as a lubricant ejector intended to limit the retention of lubricant in a critical zone of the enclosure, the ejector being intended to be passed through by a primary lubricant flow in order to drive a secondary lubricant flow located around a nozzle of the ejector housed in the critical zone of the enclosure. The enclosure includes a device for establishing communication between the drainage orifices and the ejector, such that the lubricant that escapes from the drainage orifices supplies the ejector in order to form the primary flow.

Abstract: A fuel system for a gas turbine engine includes a first electric motor, a main fuel pump driven by the first electric motor to provide a fuel flow, and an actuator operable by a second electric motor. A first motor controller governs operation of the first electric motor. A second motor controller governs operation of the second electric motor. The second motor controller is operable to control operation of the first electric motor in response the first motor controller being incapable of governing operation of the first electric motor.

Abstract: The invention relates to a lubrication device (1) for a turbo machine, comprising: a rotor (2) rotating around an axis, at least one lubrication chamber (6) formed in the rotor (2), a stator (22) in which the rotor (2) is rotatably mounted, a bearing (11) for rotationally guiding the rotor (2), mounted between the rotor (2) and the stator, lubricating fluid supply means which supply at least the chamber (6) and the bearing (11), the lubricating fluid supply means comprising a nozzle (23) mounted on the stator provided with an ejection nozzle (34) at a free end of the nozzle (23), said nozzle (34) being configured to project the lubricating fluid into the chamber (6), characterized in that the nozzle (23) has a movable part (27) including said ejection nozzle (34), said movable part (27) being movable between a retracted position in which the ejection nozzle (34) is remote from the chamber (6) or at least partially located outside the chamber (6), and an extended position in which the nozzle (34) is closer

Abstract: A ventilated chamber (19), subject to an irruption of air at a pressure higher than that in a surrounding chamber (20) through labyrinth seals separating them and evacuation of excess air through an evacuation duct (30), comprises a motor-driven compressor (32) in the evacuation duct to facilitate suction and evacuation, even when the engine speed does not allow a large overpressure in the chamber (20).

Abstract: A fan drive gear system for a turbofan engine is disclosed and includes a gear assembly and a front center body. The front center body is an annular case that supports the gear assembly. The front center body includes a passage portion that defines a portion of a core flow path, a forward flange configured for attachment to a first case structure forward of the front center body, and a gutter portion disposed on a radially inner side of the front center body for collecting lubricant exhausted from the geared assembly.

Abstract: The gas turbine engine comprises a gas generator (66), comprised of a compressor section (11), and a power turbine section (65). The power turbine section (65) comprises a power turbine rotor (81) supported by a power turbine shaft (93), which is mechanically uncoupled from the gas generator (66). The power turbine shaft (93) has an axial cavity (511) therein, fluidly coupled to a bearing sump (521) fluidly coupled to the compressor section (11) and housing at least one bearing (106) supporting a shaft of the gas generator (66). An air venting path (527) extends from said axial cavity (511) and leads in a combustion gas flow path (515) downstream of the power turbine rotor (81).

Abstract: A turbine engine of an aircraft includes: a primary air flow duct; a secondary air flow duct which is located around the primary duct, the secondary duct including a stator including a plurality of blades distributed around a main axis of the turbine engine and inter-blade platforms located between radially internal ends or between radially external ends of two adjacent blades, each platform including a wall partially delimiting the secondary duct; and a fluid circuit which includes a heat exchanger formed by at least one of the platforms. The platform includes a line that has an inlet port of the fluid and a fluid outlet port. The fluid circuit includes a distributor associated with each port of the at least one platform with the rest of the fluid circuit and of which each distributor is axially offset with respect to the platform along the main axis.

Abstract: A control device is configured to control a temperature of a shaft seal portion around a rotating shaft of a rotating machine by adjusting an amount of cooling air to be supplied to the shaft seal portion. The control device is configured to calculate a sensitivity indicated using the temperature of the shaft seal portion with respect to a flow rate of the cooling air supplied to the shaft seal portion and control the flow rate of the cooling air so that the sensitivity has a predetermined target value based on the sensitivity which has been calculated. When the sensitivity is calculated, the flow rate is varied in a predetermined range having a certain flow rate as a center. The sensitivity is calculated from variation in the temperature of the shaft seal portion with respect to variation in the flow rate.

Abstract: An oil tank filling system for filling the oil tank of a gas turbine engine that includes an aft core cowl. The system includes an oil tank that has an oil tank top and an oil tank bottom and is located within a core of the engine, an oil access port located on the aft core cowl, and an oil tank filling pipe that leads from the oil access port to a tank filling port located at or adjacent the oil tank bottom. The system is configured so that oil that is supplied to the oil access port flows to and into the oil tank using gravitational force. A method of filling the oil tank of a gas turbine engine and a gas turbine engine that includes the oil tank filling system.

Abstract: A gas turbine engine has a fan drive turbine for driving a gear reduction. The gear reduction drives a fan rotor. A lubrication system supplies oil to the gear reduction, and includes a lubricant pump to supply an air/oil mixture to an inlet of a deaerator. The deaerator includes a separator for separating oil and air, delivering separated air to an air outlet, and delivering separated oil back into an oil tank. The separated oil is first delivered into a pipe outwardly of the oil tank, and then into a location beneath a minimum oil level in the tank. Air within the oil tank moves outwardly through an air exit into the deaerator. A method of designing a gas turbine engine is also disclosed.

Abstract: A lubrication system is disclosed. In various embodiments, the lubrication system includes a storage tank configured to store a lubricant; a flow management valve configured to direct the lubricant to a starvation tolerant component and to a valve exit conduit; and a main pump configured to receive the lubricant from the storage tank and to pump the lubricant to the flow management valve and to a starvation intolerant component.

Abstract: A gas turbine engine for an aircraft including a unit supplied with oil from a first oil circuit and a second oil circuit. The first oil circuit and the second oil circuit each are fluidly coupled with at least one inlet and with at least one outlet of the unit and with at least one inlet and with at least one outlet of an oil tank. The first oil circuit and the second oil circuit are configured to receive oil from the oil tank and to direct the received oil to the unit. The oil tank is incorporating offset outlets to each of the oil circuits. The offset outlet of the second oil circuit is positioned higher in the oil tank than the offset outlet of the first oil circuit.

Abstract: Systems and methods for conditioning a fluid using bleed air from a bypass duct of a turbofan engine are disclosed. The system comprises a heat exchanger configured to facilitate heat transfer between a flow of bleed air from the bypass duct of the turbofan engine and the fluid, and a fluid propeller configured to drive the bleed air through the heat exchanger. The fluid propeller is disposed downstream of the heat exchanger.

Abstract: A turbojet includes an inlet casing, a low pressure compressor, a high pressure spool, a low pressure turbine, and an exhaust casing. The inlet casing and the low pressure compressor define an air inlet channel that divides downstream into a primary flow channel and a secondary flow channel. A low pressure shaft is supported by a first roller bearing, borne by the inlet casing, a second bearing borne by the intermediate casing, a third bearing borne by the exhaust casing, and an additional ball bearing borne by the intermediate casing and arranged between the first bearing and the second bearing. Such a configuration of bearings makes it possible to withstand an increased level of load and to be compatible with an increase in the rate of dilution.

Abstract: Aspects of the disclosure are directed to a gas turbine engine, having a fan that rotates about a central longitudinal axis. The gas turbine engine may comprise a nacelle having an outer wall that radially circumscribes the fan. The gas turbine engine may further comprise a fan drive gear system that drives the fan, and a rotating shaft that is coupled to and drives the fan drive gear system. The gas turbine engine may further comprise an air vent line in fluid communication with a bearing compartment to remove air from the bearing compartment and provide the removed air to a deoiler that removes oil droplets from the removed air and provides deoiler filtered air. A vent output line receives the deoiler filtered air and discharges the deoiler filtered air along a radially interior surface of the nacelle outer wall.

Abstract: A gas turbine engine comprising: an inner core nacelle; an outer fan nacelle; a bypass duct between the inner core nacelle and the outer fan nacelle; at least one bifurcation that extends between the inner core nacelle and the outer fan nacelle; and a cooling system, wherein the cooling system comprises at least one pipe for conveying a fluid to be cooled, the at least one pipe forming part of a fluid system of the engine, wherein the at least one pipe passes through the at least one bifurcation, and wherein at least a portion of one or more of the pipes is arranged to bring the fluid to be cooled into a heat exchanging relationship with a fluid, e.g. air, flowing in the bypass duct.