A method of operating a fuel delivery system of an aircraft engine of an aircraft includes operating the aircraft engine in a standby mode by maintaining combustion in a combustor of the aircraft engine by supplying fuel to the combustor via a first set of fuel nozzles of a first fuel manifold while providing a trickle flow of fuel via a second set of fuel nozzles of a second fuel manifold into the combustor during engine operation, the trickle flow being defined as a fuel flow rate selected to prevent flame-out of the combustion while providing one of: substantially no motive power to the aircraft, and no motive power to the aircraft, via the combustion of the trickle flow of fuel. An aircraft gas turbine engine is also described.

A lean burn fuel spray nozzle comprises: a lean burn fuel spray nozzle head comprising a pilot fuel injector with a pilot fuel injector outlet and a main fuel injector with a main fuel injector outlet; a feed arm adapted to feed pilot fuel from pilots pipework to the pilot fuel injector through a pilot fuel circuit and feed main fuel from mains pipework to the main fuel injector through a main fuel circuit; and a switching device comprising a switching valve adapted to switch between a Main On position, wherein the main fuel injector is in fluid communication with the mains pipework such that main fuel is sprayed through the main fuel injector outlet, and a Main Off position, wherein the main fuel injector outlet is not in fluid communication with the mains pipework such that main fuel is prevented to flow through the main fuel injector.

A fuel control device includes a stem fuel valve opening degree determination unit, a branch line flow rate determination unit, and a correction value determination unit. The stem fuel valve opening degree determination unit is configured to determine an opening degree of a flow rate adjustment valve of a stem fuel supply line. The branch line flow rate determination unit is configured to determine an opening degree of a flow rate adjustment valve of at least one branch line. The correction value determination unit is configured to determine a correction value of the opening degree of the flow rate adjustment valve of the at least one branch line based on a value of a pressure difference between a fuel pressure upstream of a nozzle connected to the at least one branch line and a corrected fuel pressure for a fuel pressure at an outlet.

A combustion staging system for fuel injectors of a multi-stage combustor of a gas turbine engine. The system includes plural fuel injectors, each having respective pilot and mains injection stages. It further includes a splitting unit which, to perform staging control of the combustor, receives a metered fuel flow and, for pilot and mains operation, controllably splits the received fuel flow into a pilot flow for injecting at the pilot stages of the injectors and a mains flow for injecting at the mains stages of the injectors, and for pilot-only operation, controllably splits the received fuel flow into a first part of the pilot flow for injecting at the pilot stages of a first portion of the injectors and a second part of the pilot flow for injecting at the pilot stages of a second portion of the injectors.

A system includes a flow inlet conduit and a primary conduit that branches from the flow inlet conduit for delivering flow to a set of primary nozzles. An equalization bypass valve (EBV) connects between the flow inlet conduit and a secondary conduit for delivering flow to a set of secondary nozzles. The EBV is connected to an equalization conduit (EC) to apportion flow from the flow inlet conduit to the secondary conduit. A pressure equalization solenoid (PES) is connected to the EC to selectively connect at least one of a servo supply pressure (PFA) conduit or return pressure (PDF) conduit into fluid communication with the EC. A relief management valve (RMV) is connected in the PDF conduit.

A system includes a flow inlet conduit and a primary conduit that branches from the flow inlet conduit for delivering flow to a set of primary nozzles. An equalization bypass valve (EBV) connects between the flow inlet conduit and a secondary conduit for delivering flow to a set of secondary nozzles. The EBV is connected to an equalization conduit (EC) to apportion flow from the flow inlet conduit to the secondary conduit. A pressure equalization solenoid (PES) is connected to the EC to selectively connect at least one of a servo supply pressure (PFA) conduit or return pressure (PDF) conduit into fluid communication with the EC. A relief management valve (RMV) is connected in the PDF conduit.

A controller for a gas turbine wherein the gas turbine includes the compressor arranged to operate at a rotational speed n, the combustor and the fuel supply includes the first fuel supply and the second fuel supply, wherein the compressor is arranged to provide air to the combustor at a steady state air mass flow rate m.sub.ss and wherein the fuel supply is arranged to supply fuel at a fuel mass flow rate m.sub.total to the combustor. The controller is arranged to, responsive to the load change ΔL to the load L, control the fuel supply to supply a proportion Z of the fuel mass flow rate m.sub.total as a fuel mass flow rate m.sub.fuel pilot via the first fuel supply based, at least in part, on a combustor mass flow rate m.sub.t.

A controller for a gas turbine wherein the gas turbine includes the compressor arranged to operate at a rotational speed n, the combustor and the fuel supply includes the first fuel supply and the second fuel supply, wherein the compressor is arranged to provide air to the combustor at a steady state air mass flow rate m.sub.ss and wherein the fuel supply is arranged to supply fuel at a fuel mass flow rate m.sub.total to the combustor. The controller is arranged to, responsive to the load change ΔL to the load L, control the fuel supply to supply a proportion Z of the fuel mass flow rate m.sub.total as a fuel mass flow rate m.sub.fuel pilot via the first fuel supply based, at least in part, on a combustor mass flow rate m.sub.t.

The present disclosure relates to systems and methods that are useful in control of one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants, methods of starting power production plants, and methods of generating power with a power production plant wherein one or more control paths are utilized for automated control of at least one action. The present disclosure more particularly relates to power production plants, control systems for power production plants, and methods for startup of a power production plant.

A method for controlling the fuel injection of a turbine engine using a fuel supply circuit. The supply circuit includes a pilot injection line and a main injection line. During a transition of the supply distribution between the pilot injection line and the main supply line, the method includes the following steps: a) determining at least a minimum value to be maintained for a pressure value; b) determining at least one hydraulic quantity of the supply circuit; c) based on the determined hydraulic quantity of the supply circuit, calculating a calculated fuel supply distribution value corresponding to the minimum value to be maintained; and switching the fuel supply distribution to the calculated fuel distribution value.