초록 ▼

A fan duct flow control method and apparatus is provided for controlling fan bypass airflow at an inlet into an exhaust duct cooling annulus of a variable cycle gas turbine engine. The flow control employs a translating ring as a valve-like device that interacts with an annular lip on an inlet into

A fan duct flow control method and apparatus is provided for controlling fan bypass airflow at an inlet into an exhaust duct cooling annulus of a variable cycle gas turbine engine. The flow control employs a translating ring as a valve-like device that interacts with an annular lip on an inlet into the exhaust duct cooling annulus. The translating ring is positioned to restrict airflow into the liner during appropriate periods in engine operation. This flow control is uniquely constructed to be conveniently operated by a variable cycle engine actuation system that injects fan bypass air into an engine exhaust duct. The method and apparatus in one form is also used to block fan duct flow and reduce forward thrust during aircraft taxi operations.

대표청구항 ▼

In a gas turbofan engine, with a variable area bypass injector comprising pivotally mounted chutes for injecting bypass airflow radially inward into an exhaust duct of the aircraft engine when said chutes are pivoted radially inward, an apparatus for controlling fan bypass duct airflow into an exhau

In a gas turbofan engine, with a variable area bypass injector comprising pivotally mounted chutes for injecting bypass airflow radially inward into an exhaust duct of the aircraft engine when said chutes are pivoted radially inward, an apparatus for controlling fan bypass duct airflow into an exhaust duct cooling annulus that is downstream and in direct flow communication with a bypass duct, wherein said apparatus comprises: inner and outer coaxial surfaces defining therebetween an annular inlet to said exhaust duct cooling annulus; a sealing lip on one of said coaxial surfaces, said lip extending into said annular inlet; and an annular translating member movable into and out of said annular inlet at the region of said sealing lip thereby providing a flow control for at least partially blocking airflow into said exhaust duct cooling annulus; link arms extending from said annular translating member and pivotally connected to said chutes whereby translation of said translating member for restricting airflow into the annular inlet additionally pivots said chutes radially outward to restrict injection of bypass air into the exhaust duct.