| CPC F02C 9/40 (2013.01) [F02C 9/28 (2013.01); F05D 2220/323 (2013.01); F05D 2270/08 (2013.01); F05D 2270/306 (2013.01); F05D 2270/31 (2013.01); F05D 2270/71 (2013.01)] | 18 Claims |
|
1. A computer implemented method of determining a fuel allocation for an aircraft, wherein:
the aircraft comprises a first fuel source adapted to contain a first fuel having a first fuel characteristic and a second fuel source adapted to contain a second fuel having a second fuel characteristic, the second fuel characteristic being different from the first;
the aircraft comprises one or more gas turbine engines powered by the first fuel and the second fuel from the first and second fuel sources;
the one or more gas turbine engines each comprise a staged combustion system having pilot fuel injectors and main fuel injectors, the staged combustion system being operable in a pilot-only range of operation and a pilot-and-main range of operation;
the one or more gas turbine engines each comprise a fuel delivery regulator arranged to control fuel delivery to the pilot and main fuel injectors from the first fuel source and the second fuel source,
the method comprising:
obtaining a proposed mission description comprising a list of operating points for the one or more gas turbine engines during the mission;
obtaining non-volatile particulate matter (nvPM) impact parameters for the one or more gas turbine engines, the impact parameters being associated with each operating point of the proposed mission using the first fuel from the first fuel source, the second fuel from the second fuel source, or a blend of the first fuel and the second fuel;
calculating an optimised set of one or more fuel characteristics for each operating point of the proposed mission defined in the mission description based on the nvPM impact parameters; and
determining a fuel allocation based on the optimised set of one or more fuel characteristics.
|