US 12,359,618 B2
Gas turbine fuel return line
Benjamin J Keeler, Chesterfield (GB); Craig W Bemment, Derby (GB); Andrea Minelli, Derby (GB); David M Beaven, Nottingham (GB); Paul W Ferra, Derby (GB); Christopher P Madden, Derby (GB); Peter Swann, Derby (GB); and Martin K Yates, Derby (GB)
Assigned to ROLLS-ROYCE plc, London (GB)
Filed by ROLLS-ROYCE plc, London (GB)
Filed on Jun. 25, 2024, as Appl. No. 18/753,195.
Claims priority of application No. 2319131 (GB), filed on Dec. 14, 2023.
Prior Publication US 2025/0198335 A1, Jun. 19, 2025
Int. Cl. F02C 7/14 (2006.01); F02C 7/224 (2006.01); F02C 7/232 (2006.01)
CPC F02C 7/14 (2013.01) [F02C 7/224 (2013.01); F02C 7/232 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A gas turbine engine for an aircraft, comprising:
a combustor;
a fuel-oil heat exchanger arranged to receive fuel from a fuel tank on board the aircraft and transfer heat from oil to the fuel;
a fuel return line arranged to return at least some fuel that has passed through the fuel-oil heat exchanger to the fuel tank;
a controller; and
a modulator valve arranged to modulate a flow of fuel along the fuel return line,
wherein the controller is configured to control the modulator valve such that a ratio of a temperature, in Kelvin, of fuel in the fuel tank to a temperature, in Kelvin, of fuel being delivered to the combustor is less than 0.56.