Variable area nozzle for aircraft propulsion system

1. An apparatus for an aircraft propulsion system, comprising:

a variable area nozzle apparatus including a plurality of panels, a plurality of inter-panel members, a plurality of outer panels, a plurality of outer inter-panel members and an actuation system;

the plurality of panels arranged circumferentially about an axial centerline, and the plurality of panels including a first panel and a second panel;

the plurality of inter-panel members arranged circumferentially about the axial centerline, the plurality of inter-panel members including a first inter-panel member between and connected to the first panel and the second panel, the first inter-panel member filling a gap laterally between a first side of the first panel and a second side of the second panel, and the first inter-panel member comprising an elastomeric material;

the plurality of outer panels arranged circumferentially about the axial centerline and radially outboard of the plurality of panels, the plurality of outer panels including a first outer panel and a second outer panel;

the plurality of outer inter-panel members arranged circumferentially about the axial centerline, the plurality of outer inter-panel members including a first outer inter-panel member between and connected to the first outer panel and the second outer panel, the first outer inter-panel member filling a gap laterally between a first side of the first outer panel and a second side of the second outer panel, and the first outer inter panel member comprising an elastomeric material; and

the actuation system configured to move the plurality of panels and the plurality of inter-panel members between a restricted flow arrangement and an unrestricted flow arrangement;

wherein the gap has a rectangular shape in a reference plane when the plurality of panels and the plurality of inter-panel members are in the restricted flow arrangement, and the gap has a trapezoidal shape in the reference plane when the plurality of panels and the plurality of inter-panel members are in the unrestricted flow arrangement; and

wherein the first inter-panel member projects radially out from the first panel and the second panel when in the restricted flow arrangement, and the first outer inter-panel member projects radially in from the first outer panel and the second outer panel when in the restricted flow arrangement.

2. The apparatus of claim 1 , wherein a cross-sectional area of an outlet from the variable area nozzle apparatus changes as the plurality of panels and the plurality of inter-panel members move between the restricted flow arrangement and the unrestricted flow arrangement.

3. The apparatus of claim 1 , wherein an outlet from the variable area nozzle apparatus is formed by a trailing edge of the first panel and a trailing edge of the second panel.

4. The apparatus of claim 3 , wherein the outlet from the variable area nozzle apparatus is further formed by a trailing edge of the first inter-panel member.

5. The apparatus of claim 1 , wherein

the first inter-panel member has a first sectional geometry when in the restricted flow arrangement; and

the first inter-panel member has a second sectional geometry when in the unrestricted flow arrangement, and the second sectional geometry is different than the first sectional geometry.

6. The apparatus of claim 1 , wherein the first inter-panel member is configured to at least partially unfold as the first inter-panel member moves from the restricted flow arrangement to the unrestricted flow arrangement.

7. The apparatus of claim 1 , wherein a circumferential width of the first inter-panel member is configured to increase as the first inter-panel member moves from the restricted flow arrangement to the unrestricted flow arrangement.

8. The apparatus of claim 1 , wherein

the first inter-panel member extends axially along the axial centerline between a first end and a second end; and

when in the unrestricted flow arrangement, a lateral width of the first inter-panel member at the first end is different than a lateral width of the first inter-panel member at the second end.

9. The apparatus of claim 1 , wherein at least a portion of the first panel is configured for acoustic attenuation.

10. The apparatus of claim 1 , wherein the first panel comprises a fiber-reinforced composite.

11. The apparatus of claim 1 , wherein the first panel comprises an inner skin, an outer skin and a cellular core between and connected to the inner skin and the outer skin.

12. The apparatus of claim 1 , further comprising:

a support structure;

each of the plurality of panels pivotally coupled to the support structure.

13. The apparatus of claim 1 , wherein the first panel forms a flowpath surface radially inside of the variable area nozzle apparatus.

14. The apparatus of claim 1 , wherein the first panel forms a flowpath surface radially outside of the variable area nozzle apparatus.

15. The apparatus of claim 1 , wherein

the actuation system includes a first linkage and a second linkage;

the first linkage is coupled to the first panel; and

the second linkage coupled to the second panel.

16. The apparatus of claim 1 , wherein

the actuation system includes a first linkage, a first actuator, a second linkage and a second actuator;

the first linkage couples the first actuator to the first panel;

the second linkage couples the second actuator to the second panel;

the first actuator comprises a first motor; and

the second actuator comprises a second motor.

17. The apparatus of claim 1 , wherein

the actuation system includes a first linkage, a first linear actuator, a second linkage and a second linear actuator;

the first linkage couples the first actuator to the first panel; and

the second linkage couples the second actuator to the second panel.

18. The apparatus of claim 1 , wherein the actuation system is further configured to move the plurality of outer panels and the plurality of outer inter-panel members between a restricted flow arrangement and an unrestricted flow arrangement.

19. The apparatus of claim 1 , wherein the first outer inter-panel member axially overlaps and circumferentially overlaps the first inter-panel member.

20. The apparatus of claim 1 , wherein the first inter-panel member is aligned circumferentially between a circumferentially adjacent pair of the plurality of outer inter-panel members.