A method is disclosed for controlling fuel injection in a reheat combustor of a gas turbine combustor assembly including a combustor casing defining a gas flow channel and a plurality of injection nozzles distributed in or around the gas flow channel; the method includes the step of distributing fuel among the injection nozzles according to a non-uniform distribution pattern.

A combustion staging system includes a splitting unit receiving a metered fuel flow and controllably splitting the received flow into pilot and mains flows. Pilot and mains fuel manifolds distribute fuel. A cooling flow recirculation line provides a cooling flow to the mains manifold during pilot-only operation, and a return section to collect mains manifold cooling flow. The cooling flow enters a delivery section and exits the return section. A fuel recirculating control valve on the delivery section has an open position so that the cooling flow enters the delivery section during pilot-only operation; a shut off position prevents the cooling flow entering the delivery section through the cooling flow orifice during pilot and mains operation. A supplementary valve bleeds or feeds cooling flow. The mains manifold cooling flow pressure is determined by the cooling flow and pressure raising orifices flow numbers, and a control setting of the supplementary valve.

An engine fuel control system is provided, including a supply line for the supply of fuel to a fuel metering valve which controls the flow of fuel to burners of an engine. Fuel is delivered at a first high pressure to the supply line by a pump arrangement. The engine fuel control system includes a restrictor located in the supply line for passage of the fuel delivered by the pump arrangement therethrough. The restrictor is configured such that fuel exiting the restrictor for onward supply to the fuel metering valve is at a second high pressure which is lower than the first high pressure. The engine fuel control system includes pressure limiting valves which actuate when the pressure difference between the first high and low pressure reaches a predetermined level to open a flow path for fuel on the supply line to by-pass the restrictor, thereby limiting the pressure difference.

A fuel metering valve includes a main flow path extending axially between an inlet and an outlet. Also included is a plunger disposed around a portion of a plunger guide, the plunger and the plunger guide configured to translate between an open position and a closed position to selectively distribute a fuel flowing through the main flow path to the outlet of the fuel metering valve. Further included is a solenoid coil disposed between a solenoid outer body and a solenoid inner body, the solenoid coil configured to magnetically attract the plunger to the open position. Yet further included is a secondary flow path for routing a stagnant volume of fuel upon translation of the plunger from the closed position to the open position.

An aspect includes a hybrid gas turbine engine system of a hybrid electric aircraft. The hybrid gas turbine engine system includes a gas turbine engine having a low speed spool and a high speed spool, a generator operably coupled to the low speed spool, a high spool electric motor operably coupled to the high speed spool, and a controller. The controller is configured to control the hybrid gas turbine engine system in a powered warm-up state to add heat to one or more components of the gas turbine engine by operating the gas turbine engine with a higher engine power setting above idle to drive rotation of the generator, transfer power from the generator to the high spool electric motor, and produce thrust. The gas turbine engine transitions from the powered warm-up state after reaching a target temperature of the one or more components in the powered warm-up state.

An aspect includes a hybrid gas turbine engine system of a hybrid electric aircraft. The hybrid gas turbine engine system includes a gas turbine engine having a low speed spool and a high speed spool, a generator operably coupled to the low speed spool, a high spool electric motor operably coupled to the high speed spool, and a controller. The controller is configured to control the hybrid gas turbine engine system in a powered warm-up state to add heat to one or more components of the gas turbine engine by operating the gas turbine engine with a higher engine power setting above idle to drive rotation of the generator, transfer power from the generator to the high spool electric motor, and produce thrust. The gas turbine engine transitions from the powered warm-up state after reaching a target temperature of the one or more components in the powered warm-up state.

A valve control device is provided in a gas turbine having a combustor for generating combustion gas, a turbine driven by the combustion gas generated by the combustor, a flow rate regulating valve for regulating the flow rate of the fuel to be supplied to the combustor, and a pressure regulating valve disposed upstream of the flow rate regulating valve, for regulating the fuel pressure. The valve control device controls the opening degree of the valve. The valve control device includes a load decrease detection part which detects a load decrease of the gas turbine, and a pressure control part which controls the opening degree of the valve in accordance with the output of the gas turbine. The valve control device suppresses instability of the gas turbine output even when the load rapidly decreases.

Systems and methods for monitoring fuel actuation system health are described herein. A method for monitoring fuel actuation system health may comprise: moving a metering valve from a first position to a second position; detecting a first travel distance of the metering valve; storing the first travel distance of the metering valve to memory to generate a first travel distance history; and determining a level of degradation of the fuel actuation system based on at least the first travel distance history.

A method for generating electric power for a rocket system includes burning a primary solid propellant grain to create a primary high pressure gas for providing thrust to the rocket, opening a first valve to divert a portion of the high pressure gas to an auxiliary solid propellant grain for igniting the auxiliary solid propellant grain, wherein the auxiliary solid propellant grain is disposed in a housing separate from the primary solid propellant grain, and burning the auxiliary solid propellant grain to create an auxiliary high pressure gas for turning a turbine. The method further includes driving a generator with the turbine and generating an electric power with the generator.

The invention relates to a method for metering fuel in a fuel supply circuit of an aircraft engine, the circuit comprising a metering device for a fuel circuit of an aircraft engine comprising, downstream of a fuel pumping system and upstream of injectors: —a fuel inlet (E), —a metering device (FMV) and a cut-off device (HPSOV) arranged in series, —an adjustment valve (VR) arranged on a fuel recirculation branch, such that any excess fuel supplied by the pumping system is fed back into the fuel circuit, wherein at least one flow-metric sensor (WFM1) is arranged on the recirculation branch, a density value for the metered fuel is determined according to the sensor measurements and the metering device is controlled according to the fuel density value thus determined.