Patent ID: 8480350

Claim:
A turbofan engine comprising: core and fan nacelles providing a bypass flow path having a nozzle exit area, the bypass flow path for carrying a bypass flow to be expelled from the nozzle exit area; a turbofan arranged within the fan nacelle and upstream from the core nacelle for generating the bypass flow; a spool having a turbine mounted thereon and housed within the core nacelle; a gear train interconnecting the turbofan and the spool, the turbofan coupled to the spool through the gear train; a flow control device including a surface in the bypass flow path including an aperture, the flow device adapted to introduce a fluid into the bypass flow path through the aperture for altering a boundary layer of the bypass flow that effectively changes the nozzle exit area; and a controller in communication with the flow control device, the controller configured to determine when chan es in the effective nozzle exit area are desired and command the flow control device to obtain a desired boundary layer.