US 12,378,920 B2
Gas turbine engine comprising fuel-oil heat exchangers fluidly connected to fuel spray nozzles
Christopher P Madden, Derby (GB); Craig W Bemment, Derby (GB); Andrew T Smith, Derby (GB); and Peter Swann, Derby (GB)
Assigned to ROLLS-ROYCE plc, London (GB)
Filed by ROLLS-ROYCE PLC, London (GB)
Filed on Jan. 24, 2024, as Appl. No. 18/421,471.
Application 18/421,471 is a continuation of application No. 18/211,624, filed on Jun. 20, 2023, granted, now 12,018,841.
Claims priority of application No. 2219380 (GB), filed on Dec. 21, 2022.
Prior Publication US 2024/0418129 A1, Dec. 19, 2024
Int. Cl. F02C 9/40 (2006.01); F02C 3/20 (2006.01); F02C 7/14 (2006.01); F02C 7/224 (2006.01); F02C 7/228 (2006.01); F02C 9/26 (2006.01); F23R 3/28 (2006.01); F23R 3/34 (2006.01); F02C 7/22 (2006.01)
CPC F02C 9/40 (2013.01) [F02C 3/20 (2013.01); F02C 7/14 (2013.01); F02C 7/224 (2013.01); F02C 7/228 (2013.01); F02C 9/26 (2013.01); F23R 3/28 (2013.01); F23R 3/346 (2013.01); F02C 7/22 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of operating a gas turbine engine, the gas turbine engine comprising:
a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which the first subset of fuel spray nozzles are supplied with more fuel than the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:2 to 1:5; and
one or more fuel-oil heat exchangers;
the method comprising:
providing a fuel to the one or more fuel-oil heat exchangers;
transferring heat from oil to the fuel in the one or more fuel-oil heat exchangers; and
providing the fuel from the one or more fuel-oil heat exchangers to the plurality of fuel spray nozzles; wherein
transferring heat from the oil to the fuel comprises transferring 200-600 kW/m3 of heat from oil to the fuel in the one or more fuel-oil heat exchangers at cruise conditions before providing the fuel to the plurality of fuel spray nozzles.