US 12,215,635 B2
Fuel delivery
Peter Swann, Derby (GB); Craig W Bemment, Derby (GB); and Christopher P Madden, Derby (GB)
Assigned to ROLLS-ROYCE plc, London (GB)
Filed by ROLLS-ROYCE plc, London (GB)
Filed on Jun. 9, 2023, as Appl. No. 18/208,077.
Application 18/208,077 is a continuation of application No. 17/853,191, filed on Jun. 29, 2022.
Claims priority of application No. 2205354 (GB), filed on Apr. 12, 2022.
Prior Publication US 2023/0332548 A1, Oct. 19, 2023
Int. Cl. F02C 7/22 (2006.01); B64D 27/10 (2006.01); B64D 37/30 (2006.01); F02C 9/26 (2006.01); F23R 3/36 (2006.01)
CPC F02C 9/26 (2013.01) [B64D 27/10 (2013.01); B64D 37/30 (2013.01); F02C 7/22 (2013.01); F23R 3/36 (2013.01); F05D 2220/323 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A method of operating a gas turbine engine for an aircraft, the gas turbine engine comprising 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 method comprising:
determining one or more fuel characteristics of a fuel being supplied to the staged combustion system;
determining a staging point, defining the point at which the staged combustion system is switched between pilot-only operation and pilot-and-main operation, based on the determined one or more fuel characteristics; and
controlling the staged combustion system according to the determined staging point, wherein
the one or more fuel characteristics indicate that the fuel is associated with a lower nvPM production level compared to fossil kerosene, and the one or more fuel characteristics, based on which the staging point is determined, are determined using sensor data from a sensor,
the determined staging point is a cruise staging point,
the combustion system is controlled using the determined staging point during a cruise operating condition of the engine, and
the staging point is determined such that the staged combustion system is arranged to switch between the pilot-only range of operation and the pilot-and-main range of operation at a staging point which corresponds to a steady state cruise mode of operation of the engine, the staging point defining a boundary between a first cruise operation range and a second cruise operation range.