Abstract: A thermal management system includes a thermal circuit having a thermal transport bus with a thermal fluid flowing therethrough. The thermal transport bus includes first and second bus segments. First and second thermal loads are on the first and second bus segments, respectively, and have different first and second inlet temperature requirements. The thermal management system includes a plurality of heat exchangers in thermal communication with the first and second thermal loads. The heat exchangers include a first heat exchanger and one or more second heat exchangers. The first heat exchanger is on one of the first or second bus segments for rejecting heat to engine fuel. The thermal fluid is split between each of the first and second bus segments such that only a portion of the thermal fluid flows through the first heat exchanger to accommodate the different first and second inlet temperature requirements.

Abstract: A gas turbine engine for an aircraft includes: an engine core; fan; turbomachinery bearings; power gearbox; and a heat management system configured to provide lubrication and cooling to the power gearbox and turbomachinery bearings and including at least one air-lubricant heat exchanger to dissipate a first amount of heat to a first heat sink, and at least one fuel-lubricant heat exchanger to dissipate a second amount of heat to a second heat sink, wherein the heat management system is configured to provide a first proportion of heat generated by the power gearbox and the turbomachinery and dissipated to air at 85% of a core shaft maximum take-off speed in the range of 0.25 to 0.70, and a second proportion of heat generated by the power gearbox and the turbomachinery and dissipated to air at 65% of the core shaft maximum take-off speed in the range of 0.60 to 1.

Abstract: There is provided an air pressurisation system comprising: a blower compressor coupled to a spool of a gas turbine engine and configured to receive inlet air from a bypass duct of the gas turbine engine; an air treatment apparatus to mix air from the air cycle line with air from the bypass line to control a temperature of air for discharge to an airframe system; and a core bleed line configured to provide a second inlet flow of air from a compressor of the gas turbine engine to the air treatment apparatus in an augmented air supply mode of the air pressurisation system; wherein the core bleed line is configured to provide the second inlet flow of air directly to the bypass line or mix the second inlet flow of air with air from the blower compressor upstream of the bypass line.

Abstract: A gas turbine engine includes a bypass duct, an inlet cowl, and a heat-exchanger assembly. The bypass duct is configured to direct air through a flow path to provide thrust to propel the gas turbine engine. The inlet cowl is located in the bypass duct and configured to collect a portion of the air flowing in the bypass duct. The heat-exchanger assembly is removably coupled with the inlet cowl and configured to receive the portion of the air from the inlet cowl.

Abstract: A gas turbine engine comprises at least one radially extending bleed passage optionally in fluid communication with at least one generally circumferentially extending plenum. The passage has an upstream inlet in fluid communication with a bleed passage and an outlet for releasing air from the plenum. The upstream leading edge of the inlet or the downstream trailing edge of the inlet has a non-uniform profile.

Abstract: A turbine engine for an aircraft. The turbine engine includes a combustor and a steam system. Fuel and steam are injected into the combustor to mix with compressed air to generate a fuel and air mixture. The fuel and air mixture is combusted in the combustor to generate combustion gases. The steam system is fluidly coupled to the combustor as the steam source to provide steam to the combustor. The steam system includes a hot gas path and a steam hot gas path component. The hot gas path is fluidly coupled to the combustor to receive the combustion gases and to route the combustion gases through the steam system. The steam hot gas path component includes a wall having a combustion-gas-facing surface facing the hot gas path and a hydrophobic coating formed on the combustion-gas-facing surface.

Abstract: A bleed arrangement of a gas turbine engine of an aircraft includes a core casing having one or more bleed openings define therein. The core case separates a core flowpath from a bypass flowpath of the gas turbine engine. A slider is positioned radially inboard of a case inner surface of the core casing relative to an engine central longitudinal axis. The slider is configured to be moved circumferentially between a closed position blocking the one or more bleed openings and an open position in which at least a portion of a core airflow is diverted from the core flowpath into the bypass flowpath as bleed airflow.

Abstract: A method of operating a gas turbine engine includes an engine core with a turbine, compressor, fuel combustor, and core shaft; a fan upstream of the engine core; a gearbox that receives an input from the core shaft and outputs drive to the fan; an oil loop system supplying oil to the gearbox; and a heat exchange system including: air-oil and fuel-oil heat exchangers, and wherein the oil loop system branches such that part of the oil flows along each branch and the air-oil and fuel-oil heat exchangers are parallel on different branches; and a modulation valve allows the oil sent via each branch to be varied, the method including controlling the heat exchange system wherein, under cruise conditions, a heat transfer ratio of: rate ? of ? heat ? transfer ? from ? oil ? to ? air rate ? of ? heat ? transfer ? from ? oil ? to ? fuel is in the range from 0 to 0.67.

Abstract: A combined cycle power plant comprises a gas turbine engine comprising a compressor to produce compressed gas, a combustor to produce combustion gas from compressed gas and fuel, and a turbine to receive combustion gas to produce rotational shaft power; a steam system generates steam from water using the combustion gas exiting the turbine; a first stage fuel-gas heater receives the fuel before entering the combustor and receive feedwater from the steam system to transfer heat from the feedwater to the fuel; and a second stage fuel-gas heater receives at least a portion of the fuel from the first stage fuel-gas heater to transfer heat to the fuel from a heat transfer medium before the fuel enters the combustor. A method comprises operating a gas turbine engine, operating a steam cycle, extracting compressed air for cooling the gas turbine engine, and transferring heat to fuel from the compressed air.

Abstract: A method for combined cooling and heating in an aircraft, the aircraft including an engine configured to use dihydrogen as fuel, the dihydrogen being stored in liquid form in a tank and being used in gas form in the engine, the dihydrogen being conveyed from the tank to the engine by a main pipe. The method includes the steps of branching off a part of the flow of dihydrogen in a bypass pipe, in parallel with a predefined segment of the main pipe, circulating a first heat transfer fluid in a first closed circuit, carrying out a first heat exchange between the first heat transfer fluid and the dihydrogen circulating in the bypass pipe and carrying out at least one secondary heat exchange. Each secondary heat exchange is carried out between the first heat transfer fluid and a working fluid used in the aircraft which needs to be cooled.

Abstract: A combustion section of a turbine engine having a primary combustion chamber and a secondary combustion chamber. The primary combustion chamber is defined, at least in part, by a combustor liner and a dome wall. A primary fuel nozzle having an outlet is located at the dome wall, wherein the outlet of the primary fuel nozzle is fluidly coupled with the primary combustion chamber. At least one opening located in an outer liner axially aft of the dome wall fluidly couples the secondary combustion chamber and the primary combustion chamber. A set of secondary fuel nozzles are fluidly coupled with the secondary combustion chamber.

Abstract: A gas turbine cogeneration system includes a denitration control part for outputting to a denitration device a control command to set the amount of NOx emissions at a heat recovery steam generator outlet not more than a boiler outlet target value. The denitration control part is configured to generate the control command with reference to at least a first addition amount of a reducing agent obtained by calculation based on a NOx parameter which is a parameter correlated with the amount of NOx emissions at a turbine outlet.

Abstract: Various systems, devices, and methods that may be used for increasing the efficiency of a gas turbine cycle are discussed. As an example, a method is discussed that includes using one or more blowers to increase efficiency in a turbine cycle where such blowers may be powered, for example, using energy from a stream of combustion products, from a pressurized fuel source, and/or from an electric motor. Upon reading, one of ordinary skill in the art will recognize a large variety of additional embodiments.

Abstract: A turbine engine with an axis is provided. This turbine engine includes a fan section, a turbine engine core, a bypass flowpath, a recovery system and a core flowpath. The turbine engine core is configured to power the fan section. The turbine engine core includes a core compressor section, a core combustor section and a core turbine section. The bypass flowpath is fluidly coupled with and downstream of the fan section. The recovery system includes an evaporator module and a condenser module. The condenser module is arranged radially outboard of and axially overlaps the bypass flowpath. The core flowpath extends sequentially through the core compressor section, the core combustor section, the core turbine section, the evaporator module and the condenser module.

Abstract: In certain embodiments, a rotorcraft includes a first engine, a second engine, a primary engine-start system for the first engine, a fast-start engine-start system for the first engine, and a computer system. The computer system is configured to detect a failure of the second engine during a reduced engine operation (REO) flight mode in which the first engine has been intentionally shut down inflight and the second engine is to remain operational, and to automatically initiate, in response to detecting the failure of the second engine during the REO flight mode, an automatic restart of the first engine using the fast-start engine-start system.

Abstract: Liquid fuel systems and methods are provided. A liquid fuel system includes a mixing unit and a plurality of liquid fuel supply systems. Each liquid fuel supply system is fluidly coupled to the mixing unit. The liquid fuel system further includes a controller communicatively coupled to the mixing unit and the plurality of liquid fuel supply systems. The controller includes memory and one or more processors. The memory stores instructions that when executed by the one or more processors cause the liquid fuel system to perform operations including providing one or more liquid fuels from the plurality of liquid fuel supply systems to the mixing unit. The operations further include mixing, with the mixing unit, the one or more liquid fuels to create a liquid fuel mixture. The operations further include providing the liquid fuel mixture to a combustion section of a turbomachine.

Abstract: A method for checking a closing point for a bleed-off valve for a gas turbine engine includes determining a modulation characteristic curve for the bleed-off valve, determining a nominal closing point value for the bleed-off valve on the modulation characteristic curve, operating the gas turbine engine and increasing an engine power of the gas turbine engine until the gas turbine engine parameter reaches a predetermined testing value, and determining a bleed-off valve measured value and a gas turbine engine measured value when the gas turbine engine parameter reaches the predetermined testing value. The gas turbine engine measured value is different than the nominal closing point value. The method further includes determining an extrapolated closing point value and checking the closing point for the bleed-off valve by comparing the bleed-off valve measured value or the gas turbine engine measured value to the extrapolated closing point value.

Abstract: A propulsion system for an aircraft includes a core engine that includes a core flow path where air is compressed in a compressor section, communicated to a combustor section, mixed with a gaseous fuel and ignited to generate an exhaust gas flow that is expanded through a turbine section. A fuel system supplies a fuel to the combustor through a fuel flow path, a first heat exchanger thermally communicates a first heat load into a cooling flow, a turboexpander where a heated cooling flow from the first heat exchanger is expanded to generate shaft power and cooled to provide a cooled cooling flow, and a second heat exchanger thermally communicates a second heat load to the cooled cooling flow that is communicated from the turboexpander, cooling flow from the second heat exchanger is communicated to the combustor section.

Abstract: A system is provided for a powerplant. This powerplant system includes a core compressor section, a core combustor section, a core turbine section and a core flowpath extending longitudinally through the core compressor section, the core combustor section and the core turbine section between an inlet into the core flowpath and an exhaust from the core flowpath. The powerplant system also includes a first rotating assembly, a second rotating assembly and a clutch. The first rotating assembly includes a first compressor rotor and a first turbine rotor. The first compressor rotor is arranged in the core compressor section. The first turbine rotor is arranged in the core turbine section. The second rotating assembly includes a second compressor rotor and a second turbine rotor. The second turbine rotor is arranged in the core turbine section. The clutch is configured to selectively couple the first rotating assembly to the second rotating assembly.

Abstract: A propulsion system for an aircraft includes a propulsor rotor, an engine core, a housing, a flowpath and a heat exchange system. The engine core is configured to power rotation of the propulsor rotor. The housing includes an inner structure and an outer structure. The outer structure is radially outboard of and axially overlaps the inner structure. The flowpath is downstream of the propulsor rotor and radially between the inner structure and the outer structure. The heat exchange system includes a duct, an exterior orifice, an interior orifice, a flow regulator and a heat exchanger disposed within the duct. The exterior orifice is formed by the outer structure and disposed along an exterior of the housing. The interior orifice is formed by the outer structure and disposed along the flowpath. The flow regulator is configured to selectively fluidly couple the exterior orifice and the interior orifice to the duct.