US 11,725,595 B2 · Control logic for gas turbine engine fuel economy

Abstract

A method of operating an engine of a multi-engine aircraft includes sequentially operating the engine through a plurality of cycles, each cycle including a breathing-in phase followed by a breathing-out phase. The breathing-in phase includes: i) in response to a speed of a rotor of the engine being at a sub-idle threshold, opening variable guide vanes upstream a compressor and injecting fuel into the combustor to increase rotor speed to a pre-determined upper threshold, and then ii) in response to the rotor speed reaching the pre-determined upper threshold, reducing a supply rate of fuel into the combustor and substantially closing the variable guide vanes. The breathing-out phase includes maintaining the variable guide vanes closed at least until the speed drops from the pre-determined upper threshold to the pre-determined sub-idle threshold.

Claims15

Dependent claims

A method of operating an engine of a multi-engine aircraft, comprising:

sequentially operating the engine through a plurality of cycles, a given cycle of the plurality of cycles including a breathing-in phase followed by a breathing-out phase,
the breathing-in phase including:
i) in response to a speed of a rotor of the engine being at a sub-idle threshold, opening a set of variable guide vanes upstream an air compressor section of the engine and injecting a fuel into a combustor of the engine to increase the speed to at least approximately a pre-determined upper threshold, and then
ii) in response to the speed reaching the pre-determined upper threshold, at least reducing a supply rate of the fuel into the combustor and at least substantially closing the set of variable guide vanes,
the breathing-out phase including maintaining the set of variable guide vanes closed at least until the speed drops from the pre-determined upper threshold to at least approximately the pre-determined sub-idle threshold.

2 more elements

A multi-engine aircraft, comprising:

a first engine operable to provide motive power to the aircraft;
a second engine operable to provide motive power to the aircraft;
at least one controller operatively connected to the first engine and the second engines and configured to operate the first engine in a sub-idle mode while operating the second engine in an active mode, the sub-idle mode including sequentially executing a plurality of cycles, a given cycle of the plurality of cycles including a breathing-in phase followed by a breathing-out phase,
the breathing-in phase including:
i) modulating a set of variable guide vanes upstream an air compressor section of the first engine to an open position, and modulating a fuel supply to a combustor of the first engine to an upper supply rate to increase a speed of a rotor of the first engine to an upper speed threshold, followed by ii) modulating the set of variable guide vanes to a substantially closed position, and modulating the fuel supply to a lower supply rate that is lower than the upper supply rate, in response to the speed of the rotor of the first engine reaching the upper speed threshold, and
the breathing-out phase including maintaining the set of variable guide vanes closed.

3 more elements

Dependencies are inferred from the claim text.

Control logic for gas turbine engine fuel economy

Life of this patent

Control logic for gas turbine engine fuel economy

Life of this patent

Abstract

Claims15