A method of operating a rotary machine below a minimum emissions compliance load in a response mode includes reducing a fuel split to zero. The fuel split apportions a total flow of fuel to the combustor between a first combustion zone and a second combustion zone. The method also includes determining a current operating temperature of the first combustion zone using a digital simulation of the rotary machine. The method further includes determining a target operating temperature of the first combustion zone. The target operating temperature enables the rotary machine to operate below a traditional Minimum Emissions Compliance Load (MECL) while still in compliance with emissions standards. The method also includes channeling a first flow of fuel to the first combustion zone. The first flow of fuel decreases the temperature of the first combustion zone to the target operating temperature.

A system for monitoring fuel additives on board a vehicle includes a fuel line carrying fuel from a fuel source to an engine; a fuel additive sensor configured to measure concentration of additives in fuel at a point along the fuel line; a fuel additive dispenser connected in parallel to the fuel line; at least one flow control device for controlling an amount of flow from the fuel line into the fuel additive dispenser; and a controller configured to receive input from the fuel additive sensor and to control the flow control device to adjust the amount of the flow from the fuel line into the fuel additive dispenser.

A combustion engine (10) comprises a radial compressor (16) in flow communication via a flow passage (22) with a compressor-combustor array (20) radially outward of the radial compressor (16), both rotatable around a central axis (12). The compressor-combustor (20) comprises an array of rotor blades (26). The walls of the blades (26) define a plurality of chambers (28, 30). Each chamber (28, 30) has a flow inlet (32) to receive fluid from the radial compressor (16), and a flow outlet to exhaust fluid radially outwards from the compressor-combustor (20). The plurality of chambers (28, 30) comprises a first pilot combustion chamber (28a) and a second pilot combustion chamber (28b). The first pilot combustion chamber (28a) is provided with a first fuel injector (40a), and the second pilot combustion chamber (28b) is provided with a second fuel injector (40a). The first fuel injector (40a) is in flow communication with a first fuel reservoir (70a), and the second fuel injector (40b) is in flow communication with a second fuel reservoir (70b). The first fuel reservoir (70a) and the second fuel reservoir (70b) are each in fluid communication with a flow regulator (100), the flow regulator (100, 200, 300) operable to vary fuel flow delivery rate to the first reservoir (70a) and vary fuel flow delivery rate to the second reservoir (70b). The differential regulation of fuel flow between pilot combustion chambers results in different levels of thrust being generated downstream of the combustion chambers. In this way the engine is operable to produce vectored thrust.

The invention relates to a fuel supply system of a turbomachine, including a fuel circuit having a pressurizing means at the outlet of the circuit, a pump arranged to send a flow of fuel into the circuit, and a flow sensor placed in a fuel supply duct between an outlet of the pump and the pressurizing means. The fuel circuit includes a device for regulating a flow cross section between the pump and the flow sensor, the device being activated by control means, the shaft of the pump being associated with detection means recording a speed of rotation of the shaft, and, if these detection means record a speed of rotation above a variable predetermined threshold, the regulating device is activated in order to reduce the flow sent to the flow sensor.

Systems and methods for operating systems are provided. For example, a system comprises a heat source for providing a flow of a hot fluid and a fuel flowpath for a flow of a fuel. The fuel flowpath includes a fuel accumulator and a heat exchanger for heat transfer between the hot fluid and fuel. The heat exchanger includes a hot fluid inlet for receipt of the hot fluid at an inlet temperature and a fuel inlet for receipt of the fuel at an inlet temperature. The hot fluid inlet temperature is greater than the fuel inlet temperature such that the fuel is heated through heat transfer with the hot fluid in the heat exchanger. The fuel accumulator accumulates at least a portion of the heated fuel. An exemplary system is selectively operated to heat and circulate the fuel through the fuel flowpath for consumption and/or accumulation in the fuel accumulator.

A fluid valve is provided including an inner shell and an outer shell. The inner shell includes a sidewall having a first opening and an interior surface defining an inner chamber. The outer shell includes a sidewall having a second opening and an exterior surface defining an outer chamber. The inner shell is positioned within the outer shell and the inner shell is movable relative to the outer chamber between a first position and a second position by a change in fluid conditions of a fluid supplied to the fluid valve. The first opening and the second opening overlap to define a passageway extending from the interior surface of the inner shell to the exterior surface of the outer shell. Relative movement of the inner shell from the first position toward the second position reduces a cross-sectional area of the passageway.

A fuel supply system includes a low flow circuit that branches off parallel to the main flow circuit from the upstream main flow line upstream of the metering valve and has an upstream low flow line having a line connected to an orifice having an upstream side and a downstream side. The downstream side of the orifice is connected to a mass flow meter. A return low flow line is downstream of the mass flow meter and connected into the downstream main flow line at a downstream point. A controller is programmed to take in a low flow circuit mass flow measured by the mass flow meter, and calculate a main mass flow through the main flow circuit and the total mass flow delivered to the engine. A gas turbine engine and a method of operation are also disclosed.

A fuel metering circuit for a turbomachine includes: a meter; a pump; a control valve configured to return an excess flow of fuel delivered to the meter towards the pump on the basis of a fuel pressure differential at the terminals of the meter; a diaphragm; and a volumetric flow meter. The diaphragm and the volumetric flow meter are mounted parallel to the meter, downstream of the control valve, in order to determine a density of the fuel flowing in the metering circuit.

A fuel system for a gas turbine engine includes a secondary flow lockout valve. The secondary flow lockout valve includes a valve body having a first end that defines an inlet and a second end. The valve body includes at least one primary outlet bore and at least one secondary outlet bore. The valve body defines a channel in fluid communication with the primary outlet bore. The secondary flow lockout valve includes a cover that cooperates with the second end of the valve body to define a chamber. The chamber is in fluid communication with the channel such that the valve body is movable between at least a first position in which the primary outlet bore is open and a second position in which both the primary outlet bore and the secondary outlet bore are open based on a pressure in the chamber.

A fuel supply control device controls a fuel supply pump based on a front-rear differential pressure across a metering valve for a fuel supply amount, which is detected by a differential pressure gauge, using parallel flow passages of an orifice and a pressurizing valve as the metering valve, in which the fuel supply control device includes a first control amount generation unit generating a first control amount based on the front-rear differential pressure, a second control amount generation unit generating a second control amount based on the rotation speed of the fuel supply pump, a control amount selection unit, a subtractor, and a control calculation unit, in which the control amount selection unit selects the first control amount in a case where the rotation speed is equal to or lower than a predetermined threshold and select the second control amount in a case where the rotation speed exceeds the threshold.