Air inlet for an aircraft propulsion unit comprising mobile members for promoting a thrust reversal phase, and method for using such an air inlet

1. An air inlet of a nacelle of an aircraft propulsion unit, said aircraft propulsion unit extending along a longitudinal axis oriented from upstream to downstream and comprising a turbine engine comprising a radially inner primary duct and a radially outer bypass duct configured to guide from upstream to downstream respectively a primary air flow and a bypass air flow during a thrust phase, said turbine engine comprising upstream a fan rotatably mounted about the longitudinal axis, said aircraft propulsion unit comprising thrust inversion means configured to modify the bypass air flow into a reverse air flow circulating from downstream to upstream in the bypass duct during a thrust reversal phase, said nacelle extending outwardly around the turbine engine and comprising at its upstream end the air inlet, said air inlet comprising an inner wall turned towards the longitudinal axis, an outer wall opposite the inner wall and an air inlet lip connecting upstream the inner wall and the outer wall, wherein:

the inner wall defines a plurality of openings comprising an upstream end and a downstream end, and

the air inlet comprises a plurality of mobile members, a mobile member of the plurality of mobile members being mounted pivoting in each opening of the plurality of openings, each of the mobile members comprising a covering wall and a deflecting wall opposite the covering wall and being configured to pivot between:

a covering position, wherein the covering wall is turned towards the longitudinal axis, obstructs the opening and extends along the inner wall so as to guide the bypass air flow in order to promote the thrust phase, and

a deflecting position, wherein the deflecting wall is turned towards the longitudinal axis, obstructs the opening and is configured to separate the reverse air flow in order to promote the thrust reversal phase.

2. The air inlet according to claim 1 , wherein each of the mobile members comprises a separating end connecting the covering wall and the deflecting wall, said separating end being configured, in the deflecting position, to extend radially inward with respect to the inner wall.

3. The air inlet according to claim 2 , wherein the separating end comprises a pointed shape.

4. The air inlet according to claim 2 , wherein the separating end is configured, in the covering position, to extend adjacent to the downstream end.

5. The air inlet according to claim 1 , wherein each of the mobile members comprises a blocking end that connects the covering wall and the deflecting wall, said blocking end being configured to cooperate with the upstream end in the covering position and with the downstream end in the deflecting position.

6. The air inlet according to claim 5 , wherein the blocking end is configured to move radially outwards to the inner wall wall between the covering position and the deflecting position.

7. The air inlet according to claim 1 , wherein each of the mobile members is mounted mobile around a pivot of pivot axis tangential to the inner wall and belonging to a plane transverse to the longitudinal axis.

8. The air inlet according to claim 7 , wherein the mobile member extends on either side of the pivot.

9. An aircraft propulsion unit extending along a longitudinal axis oriented from upstream to downstream and comprising a turbine engine comprising a radially inner primary duct and a radially outer bypass duct configured to guide from upstream to downstream respectively a primary air flow and a bypass air flow during a thrust phase, said turbine engine comprising upstream a fan rotatably mounted about the longitudinal axis, said aircraft propulsion unit comprising thrust inversion means configured to modify the bypass air flow into a reverse air flow circulating from downstream to upstream in the bypass duct during a reverse thrust phase, said nacelle extending outwardly around the turbine engine and comprising at its upstream end an air inlet comprising an inner wall turned towards the longitudinal axis, an outer wall opposite the inner wall and an air inlet lip connecting upstream the inner wall and the outer wall, wherein:

the inner wall defines a plurality of openings comprising an upstream end and a downstream end, and

the air inlet comprises a plurality of mobile members, a mobile member of the plurality of mobile members being mounted pivoting in each opening of the plurality of openings, each of the mobile members comprising a covering wall and a deflecting wall opposite the covering wall and being configured to pivot between:

a covering position, wherein the covering wall is turned towards the longitudinal axis, obstructs the opening and extends along the inner wall so as to guide the bypass air flow in order to promote the thrust phase, and

a deflecting position, wherein the deflecting wall is turned towards the longitudinal axis, obstructs the opening and is configured to separate the reverse air flow in order to promote the thrust reversal phase.

10. A method for using an air inlet of an aircraft propulsion unit according to claim 1 , wherein each of the mobile members is initially in the covering position so as to guide the bypass air flow in order to promote the thrust phase, said method comprising, during the thrust reversal phase, a movement of each of the mobile members in the deflecting position so as to separate the reverse air flow.

11. The air inlet according to claim 3 , wherein the pointed shape of the separating end defines an angle of less than 30°.

12. The air inlet according to claim 8 , wherein the pivot is mounted closer to the upstream end than to the downstream end of the opening.

13. The aircraft propulsion unit according to claim 9 , wherein the fan comprises variable pitch blades so as to form the thrust reversal means.