AIRCRAFT PROPULSION SYSTEM INCLUDING A HEAT EXCHANGER SYSTEM

The invention relates to an aircraft propulsion system, which includes a turbojet and a heat exchanger system (200) which includes a main heat exchanger (202), a supply pipe (204) supplying hot air and including a regulating valve (214), a high pressure pipe (250) bleeding hot air from a high pressure stage (206) through a first valve (210), an intermediate pressure pipe (252) bleeding hot air from an intermediate pressure stage (208) through a second valve (212), a transfer pipe (222) transferring the hot air to an air management system, a main supply pipe (216) supplying cold air from the fan duct and including a main regulating valve (218), an evacuation pipe (220) expelling the air to the outside, a sub heat exchanger (230), wherein the high pressure pipe (250) goes through the sub heat exchanger (230), a sub supply pipe (232) supplying cold air from the fan duct and including a sub regulating valve (234), a sub evacuation pipe (236) expelling the air to the fan duct, a temperature sensor (223) measuring the temperature of the hot air exiting the main heat exchanger (202), and a control unit (224) which controls the valves according to the temperature measured by the temperature sensor (223).The embodiment including two separate heat exchangers induces a size reduction of the main heat exchanger and a better integration in the reduced space between the pylon and the pylon fairing.