초록 ▼

A fan variable area nozzle (FVAN) includes a flap driven through a cable which circumscribes the fan nacelle. The cable is strung through a multiple of flaps to define a flap set of each circumferential sector of the EVAN. An actuator system includes a compact high power density electromechanical ac

A fan variable area nozzle (FVAN) includes a flap driven through a cable which circumscribes the fan nacelle. The cable is strung through a multiple of flaps to define a flap set of each circumferential sector of the EVAN. An actuator system includes a compact high power density electromechanical actuator which rotates a spool to deploy and retract the cable and effectively increase or decrease the length thereof between the spool and a fixed attachment to increase and decrease the fan nozzle exit area.

대표청구항 ▼

1. A method of providing a variable fan exit area of a high-bypass gas turbine engine comprising the steps of: (A) locating a fan variable area nozzle to define a fan nozzle exit area for flow passing between a fan nacelle and a core nacelle;(B) stringing a cable to pass through a fan nacelle first

1. A method of providing a variable fan exit area of a high-bypass gas turbine engine comprising the steps of: (A) locating a fan variable area nozzle to define a fan nozzle exit area for flow passing between a fan nacelle and a core nacelle;(B) stringing a cable to pass through a fan nacelle first fixed engagement structure, then through a flap extension opening and then through a fan nacelle second fixed engagement structure wherein the flap extension opening is located between the first fixed engagement structure and the second fixed engagement structure;(C) locating said flap extension opening in a flap extension protruding from a leading edge of a flap, said flap extension opening upstream of a flap pivot point, said fan nacelle first fixed engagement structure and said fan nacelle second fixed engagement substantially aligned with lateral sides of said flap and at least one of said first and second fixed engagement structures having a cable opening located upstream of said flap pivot point;(D) providing an actuator system that includes a spool engaged with said cable, a segment of said cable opposite said actuator system being attached to a fixed structure within said fan nacelle;(E) spooling and unspooling the cable engaged with said fan variable area nozzle to vary the fan nozzle exit area by pivoting a plurality of said flaps to adjust fan bypass airflow such that an angle of attack of turbofan fan blades are maintained close to design incidence; and(F) wherein unspooling said cable extends the cable to enable said flow to urge a trailing edge of at least one of said plurality of said flaps outwardly and increase said area. 2. A method as recited in claim 1, wherein said step (B) further comprises: (a) spooling the cable to converge the fan nozzle exit area during cruise flight condition. 3. A method as recited in claim 1, wherein said step (B) further comprises: (a) stringing one end of the cable about the spool and the opposite end of the cable to the fixed structure with said plurality of said flaps strung therebetween. 4. A method as recited in claim 1, wherein the actuator system comprises a rotary hydraulic actuator. 5. A nacelle assembly for a gas turbine engine comprising: a core nacelle defined about an axis for allowing flow to pass therethrough;a fan nacelle mounted at least partially around said core nacelle, said fan nacelle having a plurality of lateral ribs and a fan variable area nozzle that defines a fan exit area between said fan nacelle and said core nacelle, said nozzle having a plurality of flaps that pivot about a pivot, each flap associated with a pair of said lateral ribs, at least one of the pair of lateral ribs having a rib orifice located upstream of a leading edge of said each flap, said each flap having an extension protruding from said leading edge upstream of said pivot and between said pair of lateral ribs;a cable engaged with said fan variable area nozzle within said fan nacelle, said cable routed from the rib orifice in one of said pair of lateral ribs, said cable then routed through an orifice in said extension, said cable then routed to the other of said pair of lateral ribs; and,an actuator system that mechanically retracts said cable therein pivoting a trailing edge of said flaps about said pivot inwardly to lessen said fan exit area and mechanically extends said cable to enable said flow to pivot said trailing edge of said flaps about said pivot outwardly and increase said fan exit area, wherein said actuator system is engaged with said cable, and a segment of said cable, opposite said actuator system, is attached to a fixed structure within said fan nacelle. 6. The nacelle assembly as recited in claim 5, wherein said actuator system includes a spool configured to spool and unspool said cable. 7. The nacelle assembly as recited in claim 5, wherein said actuator system includes a spool engaged with said cable. 8. The nacelle assembly of claim 7, wherein spooling of the cable around the spool decreases the fan nozzle exit area. 9. The nacelle assembly of claim 7, wherein unspooling of the cable around the spool increases the fan nozzle exit area. 10. The nacelle assembly as recited in claim 5, wherein said fan variable area nozzle includes a multiple of flap sets, each of said flap sets separately driven by a respective cable and actuator of said actuator system to asymmetrically and symmetrically adjust said fan variable area nozzle. 11. The nacelle assembly of claim 10, wherein each flap set corresponds to a circumferential sector of the fan variable area nozzle. 12. The nacelle assembly of claim 11, wherein there are four circumferential sectors. 13. The nacelle assembly as recited in claim 5, further comprising: a gear system driven by a core engine; anda fan driven by said gear system about said axis. 14. The nacelle assembly of claim 5, wherein the actuator system comprises one of an electromechanical actuator or a rotary hydraulic actuator. 15. The nacelle assembly for a gas turbine engine of claim 5 wherein there is one actuator system for a set of flaps. 16. The nacelle assembly of claim 5, wherein the actuator system comprises a rotary hydraulic actuator. 17. The nacelle assembly of claim 5, wherein the cable circumscribes the fan nacelle. 18. The nacelle assembly of claim 5, wherein the fixed structure is a fan nacelle rib. 19. An assembly for pivoting a plurality of flaps, said assembly disposed about an axis along which a flow passes from an upstream direction to a downstream direction, said assembly comprising: a structure mounted at least partially around said axis, said structure having plurality of lateral ribs, said structure having a plurality of pivots attaching thereto, each pivot attaching to a flap wherein said plurality of flaps define a nozzle area and wherein each flap pivots about said pivot, each flap associated with a pair of said lateral ribs, at least one of the pair of lateral ribs having a rib orifice located upstream of a leading edge of said each flap, said each flap having an extension protruding from said leading edge upstream of said pivot and between said pair of lateral ribs;a cable engaged with said nozzle within said structure, said cable routed from the rib orifice in one of said pair of lateral ribs, said cable then routed through an orifice in said extension, said cable then routed to the other of said pair of lateral ribs; andan actuator system that mechanically retracts said cable therein to lessen the nozzle area and mechanically extends said cable to enable said flow to urge said flaps outwardly and increase said area, wherein: said actuator system engaged with said cable, and a segment of said cable, opposite said actuator system, is attached to a fixed structure within said fan nacelle.