A system has first and second fuel stores for first and second fuels, an engine, a fuel distribution system, first and second flow rates of the fuel contributing to a total flow rate of fuel; and a controller for controlling the relative fractions of the total flow rate of fuel to the engine according to the required power output of the engine such that the relative fraction of the total flow rate of fuel to the engine represented by the second flow rate increases with increasing required power output of the engine. The fuels are selected such that using only the second fuel results in a lower engine temperature than using only the first fuel, for the same mechanical power and/or the second fuel has a lower specific energy than the first and/or the second fuel produces more water during combustion than the first fuel per unit of fuel energy.

An emission reduction system for a combined cycle power plant including a gas turbine and heat recovery steam generator (HRSG) can comprise a stationary emission converter in fluid communication with and disposed upstream of the HRSG, and a diversion system operably coupled to an exhaust passage of the gas turbine, the exhaust passage defining an exhaust path for exhaust gas of the gas turbine through the heat recovery steam generator, the diversion system operable to define a primary exhaust path excluding the stationary emission converter and a start-up exhaust path including the stationary emission converter.

Apparatuses for generating carbon particles and exhaust gas used by gas turbine systems are disclosed. One apparatus may include a decarbonization component combusting or reacting a mixture of a fuel and a mixing gas to generate the carbon particles and the exhaust gas and an exhaust conduit to receive the exhaust gas generated by the decarbonization component. The apparatus may also include a mixing duct in fluid communication with the exhaust conduit and the gas turbine system. The mixing duct may receive the exhaust gas and provide the exhaust gas to the gas turbine system to be used to produce a working fluid within the gas turbine system. The apparatus may further include a carbon particle collection component for receiving and storing the generated carbon particles.

A combustor assembly comprising a deflector wall in which a plurality of openings is defined through the deflector wall and around the fuel nozzle opening. The plurality of openings defines a first set of openings at a first radius, a second set of openings at or greater than a second radius greater than the first radius, and a third set of openings at one or more of a third radius between the first radius and the second radius. The first set of openings defines one or more of a first angle relative to the radial direction between approximately 60 degrees and approximately 100 degrees. The second set of openings defines one or more of a second angle between approximately zero and approximately 30 degrees. The third set of openings defines one or more of a third angle between the first angle and the second angle.

An emission reduction system for a combined cycle power plant including a gas turbine and heat recovery steam generator (HRSG) can comprise a stationary emission converter in fluid communication with and disposed upstream of the HRSG, and a diversion system operably coupled to an exhaust passage of the gas turbine, the exhaust passage defining an exhaust path for exhaust gas of the gas turbine through the heat recovery steam generator, the diversion system operable to define a primary exhaust path excluding the stationary emission converter and a start-up exhaust path including the stationary emission converter.

An aircraft has first and second fuel sources containing fuels with different characteristics, and one or more gas turbine engines powered by the fuels and each having a staged combustion system having pilot and main fuel injectors and being operable in pilot-only and pilot-and-main ranges of operation. The gas turbine engines each have a fuel delivery regulator arranged to control fuel delivery to the pilot and main fuel injectors. The method includes: obtaining a proposed mission description; obtaining nvPM impact parameters for the gas turbine engines, the impact parameters being associated with each operating condition of the proposed mission; calculating an optimised set of one or more fuel characteristics for each flight condition of the proposed flight defined in the flight description based on the nvPM impact parameters; and determining a fuel allocation based on the optimised set of one or more fuel characteristics.

An aircraft has first and second fuel sources containing fuels with different characteristics, and one or more gas turbine engines powered by the fuels and each having a staged combustion system having pilot and main fuel injectors and being operable in pilot-only and pilot-and-main ranges of operation. The gas turbine engines each have a fuel delivery regulator arranged to control fuel delivery to the pilot and main fuel injectors. The method includes: obtaining a proposed mission description; obtaining nvPM impact parameters for the gas turbine engines, the impact parameters being associated with each operating condition of the proposed mission; calculating an optimised set of one or more fuel characteristics for each flight condition of the proposed flight defined in the flight description based on the nvPM impact parameters; and determining a fuel allocation based on the optimised set of one or more fuel characteristics.

The present invention relates to an aircraft comprising at least one wing, at least one flight propulsion drive, and a retainer, particularly an engine pylon, which interconnects the wing and the flight propulsion drive. The aircraft comprises at least one heat exchanger for cooling exhaust gas of the fight propulsion drive and/or at least one water removal channel having at least one removal apparatus for removing water from exhaust gas of the flight propulsion drive, especially after the exhaust gas has flowed through the heat exchanger. The removal apparatus is disposed on, more particularly in, the retainer or is connected to the wing by means of the retainer, and/or the flight propulsion drive is fastened to the retainer by means of at least one flight propulsion drive suspension means, and the heat exchanger is fastened, independently thereof, to the retainer by means of at least one heat exchanger suspension means.

An aircraft propulsion system includes first and second engines and first and second electrical machines coupled to the first and second engines respectively. The first electrical machine is arranged to be driven by electrical power in order to at least partially drive the first engine. The second electrical machine is arranged to be driven by the second engine to generate electrical power. An electrical network allows transmission of electrical power between the electrical machines. A controller is arranged to selectively reduce fuel flow to the first engine and provide electrical power from the second electrical machine to the first electrical machine to drive the first electrical machine, based on expected properties of contrails formed in an exhaust plume of the first engine and/or the second engine. The system allows the formation of contrails by the engines to be managed in order to mitigate climate-warming effects of the contrails.

A method is provided during which an aircraft powerplant is provided. The aircraft powerplant includes a combustor and a water recovery system. The water recovery system includes a condenser and a reservoir. Fuel is combusted within the combustor to provide combustion products. Water is extracted from the combustion products using the condenser. The water recovery system is operated in one of a plurality of modes based on likelihood of contrail formation. The modes include a first mode and a second mode, where the water is collected within the reservoir during the first mode, and where the water passes through the water recovery system during the second mode.