Flexible sleeve for adjustable fan duct nozzle
A ducted fan housing for directing a duct flow includes an annular cowling and an adjustable fan duct nozzle. The nozzle includes a flexible sleeve having rigid areas arranged circumferentially around the nozzle orifice and connected by flexible areas so as to form a unitary sleeve structure. The rigid areas are radially moveable between a normal configuration in which the orifice is smaller and a dilated configuration in which the orifice is larger. A drive mechanism uses drive elements to move at least some of the rigid areas between the configurations to adjust the size of the orifice. The rigid areas may be constructed from laminated graphite and epoxy, and the flexible areas may be constructed from laminated graphite and soft resin. If the housing includes a thrust reverser, then a flexible joint area extends circumferentially around the housing and connects the flexible sleeve to a thrust reverser cowl.
1. A ducted fan housing for directing a duct flow generated by a fan in a rearward direction, the ducted fan housing comprising:
an annular cowling having an aft end and surrounding the fan and extending rearwardly of the fan to the aft end, and fluidly engaging the duct flow; and
an adjustable fan duct nozzle located at the aft end of the annular cowling and comprising a nozzle orifice and fluidly engaging the duct flow from the annular cowling, the adjustable fan duct nozzle comprising—
a flexible sleeve extending continuously around the nozzle orifice as a single seamless structure and comprising a plurality of rigid areas spaced circumferentially and non-overlappingly apart and radially moveable to change the flexible sleeve between a normal configuration in which the nozzle orifice is smaller and a dilated configuration in which the nozzle orifice is larger, wherein the flexible sleeve further comprises flexible areas that separate the rigid areas and remains the single seamless structure without gaps in and between the normal configuration and the dilated configuration, and
a drive mechanism moving at least some rigid areas of the plurality of rigid areas between the normal configuration and the dilated configuration so as to adjust the nozzle orifice and thereby control the duct flow passing through the adjustable fan duct nozzle.
2. The ducted fan housing of claim 1 , the rigid areas comprising a plurality of drive areas and a plurality of driven areas alternatingly arranged with and separating the drive areas and seamlessly and flexibly connected to the drive areas so that movement of the drive areas is transmitted by the flexible areas to the driven areas, wherein the flexible sleeve remains the single seamless structure without gaps between the drive areas and the driven areas in and between the normal configuration and the dilated configuration.
3. The ducted fan housing of claim 2 , wherein the plurality of drive areas are constructed at least in part from laminated graphite and epoxy.
4. The ducted fan housing of claim 2 , wherein the plurality of driven areas are constructed at least in part from laminated graphite and soft resin.
5. The ducted fan housing of claim 1 , wherein the drive mechanism comprises one or more drive elements attached to the at least some rigid areas of the plurality of rigid areas and transferring a drive force to move the at least some rigid areas between the normal configuration and the dilated configuration.
6. The ducted fan housing of claim 5 , wherein each of the one or more drive elements comprises an axially extending lever pivotally attached to a bracket.
7. The ducted fan housing of claim 6 , wherein each of the one or more drive elements comprises a cam transferring the drive force to the axially extending lever.
8. The ducted fan housing of claim 5 , wherein each of the one or more drive elements is constructed at least in part from a shape memory alloy material.
9. The ducted fan housing of claim 1 , wherein the plurality of rigid areas are naturally biased toward the dilated configuration so as to be naturally urged toward the dilated configuration when placed in the normal configuration.
10. The ducted fan housing of claim 1 , wherein the plurality of rigid areas are naturally biased toward the normal configuration so as to be naturally urged toward the normal configuration when placed in the dilated configuration.
11. The ducted fan housing of claim 1 , wherein—
the ducted fan housing further comprises a thrust reverser;
the annular cowling further comprises a rigid inner acoustic panel and a rigid outer thrust reverser cowl; and
the flexible sleeve further comprises a flexible joint area extending circumferentially around the ducted fan housing and connecting the flexible sleeve to the thrust reverser cowl so as to allow independent deployment of the thrust reverser and adjustment of the nozzle orifice, wherein each of the inner acoustic panel and the thrust reverser cowl comprises the plurality of rigid areas which allow for adjusting the nozzle orifice.
12. A ducted fan housing for directing a duct flow generated by a fan of an aircraft engine in a rearward direction, the ducted fan housing comprising:
an annular cowling having an aft end and surrounding the fan and extending rearwardly of the fan to the aft end, and fluidly engaging the duct flow; and
an adjustable fan duct nozzle located at the aft end of the annular cowling and comprising a nozzle orifice and fluidly engaging the duct flow from the annular cowling, the adjustable fan duct nozzle comprising—
a flexible sleeve extending continuously around the nozzle orifice as a single seamless structure and comprising—
a plurality of flexible areas,
a plurality of drive areas spaced circumferentially apart and radially moveable to change the flexible sleeve between a normal configuration in which the nozzle orifice is smaller and a dilated configuration in which the nozzle orifice is larger,
a plurality of driven areas alternatingly arranged with and separating the drive areas and seamlessly, flexibly, and non-overlappingly connected by the flexible areas to the drive areas so that movement of the drive areas is transmitted by the flexible areas to the driven areas,
wherein the flexible areas separate the plurality of drive areas from the plurality of driven areas and the flexible sleeve remains the single seamless structure without gaps between the plurality of drive areas and the plurality of driven areas in and between the normal configuration and the dilated configuration, and
a drive mechanism moving at least some of the plurality of drive areas between the normal configuration and the dilated configuration so as to adjust the nozzle orifice and thereby control the duct flow passing through the adjustable fan duct nozzle.
13. The ducted fan housing of claim 12 , wherein the plurality of drive areas are constructed at least in part from laminated graphite and epoxy, and the plurality of driven areas are constructed at least in part from laminated graphite and soft resin.
14. The ducted fan housing of claim 12 , wherein the drive mechanism comprises one or more drive elements attached to the drive areas and transferring a drive force to move the drive areas between the normal configuration and the dilated configuration, wherein each of the one or more drive elements comprises an axially extending lever pivotally attached to a bracket and a cam transferring the drive force to the axially extending lever.
15. The ducted fan housing of claim 12 , wherein the drive mechanism comprises one or more drive elements attached to the drive areas and transferring a drive force to move the drive areas between the normal configuration and the dilated configuration, wherein each of the one or more drive elements is constructed at least in part from a shape memory alloy material.
16. A ducted fan housing for directing a duct flow generated by a fan of an aircraft engine in a rearward direction, the ducted fan housing comprising:
a thrust reverser;
an annular cowling having an aft end and surrounding the fan and extending rearwardly of the fan to the aft end, and fluidly engaging the duct flow, the annular cowling comprising a rigid inner acoustic panel and a rigid outer thrust reverser cowl; and
an adjustable fan duct nozzle located at the aft end of the annular cowling and comprising a nozzle orifice and fluidly engaging the duct flow from the annular cowling, the adjustable fan duct nozzle comprising—
a flexible sleeve extending continuously around the nozzle orifice as a single seamless structure and comprising—
a plurality of flexible areas,
a plurality of drive areas spaced circumferentially apart and radially moveable to change the flexible sleeve between a normal configuration in which the nozzle orifice is smaller and a dilated configuration in which the nozzle orifice is larger, and
a plurality of driven areas alternatingly arranged with and separating the drive areas and flexibly and non-overlappingly connected by the flexible areas to the drive areas so that movement of the drive areas is transmitted by the flexible areas to the driven areas,
wherein the flexible areas separate the plurality of drive areas from the plurality of driven areas and the flexible sleeve remains the single seamless structure without gaps in and between the normal configuration and the dilated configuration,
a drive mechanism moving at least some of the plurality of drive areas between the normal configuration and the dilated configuration so as to adjust the nozzle orifice and thereby control the duct flow passing through the adjustable fan duct nozzle, and
a flexible joint area extending circumferentially around the ducted fan housing and connecting the flexible sleeve to the thrust reverser so as to allow independent deployment of the thrust reverser and adjustment of the nozzle orifice.
17. The ducted fan housing of claim 16 , wherein the plurality of drive areas are constructed at least in part from laminated graphite and epoxy, and the plurality of driven areas are constructed at least in part from laminated graphite and soft resin.
18. The ducted fan housing of claim 16 , wherein the flexible sleeve remains the single seamless structure without gaps between the plurality of drive areas and the plurality of driven areas in and between the normal configuration and the dilated configuration.
19. The ducted fan housing of claim 16 , wherein the drive mechanism comprises one or more drive elements attached to the drive areas and transferring a drive force to move the drive areas between the normal configuration and the dilated configuration, wherein each of the one or more drive elements comprises an axially extending lever pivotally attached to a bracket and a cam transferring the drive force to the axially extending lever.
20. The ducted fan housing of claim 16 , wherein the drive mechanism comprises one or more drive elements attached to the drive areas and transferring a drive force to move the drive areas between the normal configuration and the dilated configuration, wherein each of the one or more drive elements is constructed at least in part from a shape memory alloy material.