This application belongs to the technical field of aircraft engine design, and specifically relates to a three-duct variable-cycle aircraft engine.
A third duct is added between the inner duct and the outer duct, and a diversion fan is added behind the main fan. The diversion fan further includes:
a first-stage diversion fan
a second-stage diversion fan
The first-stage diversion fan is located inside the inlet of the third duct, in front of the inner duct.
The second-stage diversion fan is located inside the inlet of the inner duct.
The first-stage and second-stage diversion fans are connected by a drum/casing.
The second-stage diversion fan is connected to the front end of the low-pressure shaft through a diversion-fan shaft.
A variable-speed gearbox is connected inside the front end of the low-pressure shaft, and the output shaft of the variable-speed gearbox is connected to the fan through a fan shaft.