摘要 |
The present inventions include a boundary layer ejector fluidically connecting boundary layer bleed slots from an external surface of an aircraft to reduce aircraft/nacelle/pylon drag, reduce jet noise and decrease thrust specific fuel consumption. In one embodiment a boundary layer withdrawn through the boundary layer bleed slots is entrained with an exhaust flow of a gas turbine engine. In another embodiment a boundary layer withdrawn through the boundary layer bleed slots is entrained with a flow stream internal to the gas turbine engine, such as a fan stream of a turbofan. A moveable shroud can be used to open and close a passage of an ejector which can be used to assist in withdrawing a boundary layer or entrain an ambient air. A lobed mixer can be used in some embodiments to effect mixing between the boundary layer and a primary fluid of the ejector. |