Multi-engine system and method
AssigneePratt & Whitney Canada Corp.
InventorsKeith MORGAN, Stephen MAH, Philippe BEAUCHESNE-MARTEL, Eric DUROCHER
Life of this patent
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Abstract
A method of operating a multi-engine system of a rotorcraft includes, during a cruise flight segment of the rotorcraft, controlling a first engine to provide sufficient power and/or rotor speed demands of the cruise flight segment; and controlling a second engine to by providing a fuel flow to the second engine that is between 70% and 99.5% less than a fuel flow provided to the first engine. A turboshaft engine for a multi-engine system configured to drive a common load is also described.
Claims22
A method of operating a multi-engine system of a rotorcraft, comprising:
- during a cruise flight segment of the rotorcraft, controlling a first engine to provide sufficient power and/or rotor speed demands of the cruise flight segment;
- and
- controlling a second engine to provide a fuel flow to the second engine that is between 70% and 99.5% less than a fuel flow provided to the first engine.
A multi-engine system for a rotorcraft comprising:
- a first turboshaft engine and a second turboshaft engine driving a common gearbox configured to drive a load, at least the second turboshaft engine having:
- a low pressure spool having a low pressure compressor and a low pressure turbine section, the low pressure compressor section including a mixed flow rotor, a high pressure spool having a high pressure compressor and a high pressure turbine section, the spools independently rotatable relative to one another, a set of variable guide vanes (VGVs) upstream of each of the low pressure and high pressure compressors, the VGVs configured to be independently operable relative to one another, and
- a controller configured to control fuel flow to the engines, including controlling the fuel flow to the second engine in a selected mode to be between 70% and 99.5% less than a fuel flow to the first engine.
A turboshaft engine for a multi-engine system configured to drive a common load, the turboshaft comprising:
- at least two spools independently rotatable relative to each other, a low pressure spool of the at least two spools including a low pressure shaft interconnecting a low pressure compressor section to a low pressure turbine section, and a high pressure spool of the at least two spools including a high pressure shaft interconnecting a high pressure compressor section to a high pressure turbine section, the low pressure compressor section being defined by a single mixed flow rotor;
- a plurality of sets of variable guide vanes comprising a set of variable guide vanes disposed at an inlet of each one of the at least two spools, a first set of the plurality of sets being mechanically decoupled from a second set of the plurality of sets, and
- an engine controller configured to control fuel flow to the engine to operate the engine at a rotational speed lower than an idle speed of the engine.
Dependencies are inferred from the claim text.