THRUST REVERSER CASCADE INCLUDING ACOUSTIC TREATMENT

Abstract

A cascade type thrust reverser device for a turbomachine of an aircraft, comprising a thrust reverser cascade and a casing, the cascade including first cavities, and the casing comprising an opening defining a housing wherein said cascade can be inserted in a first direction, and the casing and said cascade being in relative translation with respect to one another in the first direction between a first position of the device in which the cascade is entirely positioned in the housing and a second position of the device in which said cascade is at least partially outside said housing. The casing comprises an acoustic treatment panel including second cavities extending in a second plane parallel to the first plane, each first cavity facing a second cavity when the device is in the first position to form an acoustic treatment cell.

Claims

1. A cascade type thrust reverser device for a turbomachine of an aircraft, comprising a thrust reverser cascade and a casing, the cascade extending in a first plane defining a first direction and a second direction and including first cavities, the casing comprising an opening extending in a plane orthogonal to said first direction and defining a housing wherein the cascade can be inserted in said first direction, and the casing and said cascade being in relative translation with respect to one another in the first direction between a first position of the device in which the cascade is entirely positioned in the housing and a second position of the device in which said cascade is at least partially outside said housing, wherein the casing comprises an acoustic treatment panel including second cavities extending in a second plane parallel to the first plane, each first cavity facing a second cavity when the device is in the first position to form an acoustic treatment cell.

2. The cascade type thrust reverser device according to claim 1, wherein said thrust reverser cascade comprises first partitions positioned successively in a first direction and parallel to one another and first transverse partitions intersecting said first partitions and each extending in planes parallel to one another and parallel to the first direction, said acoustic treatment panel comprises second partitions positioned successively in the first direction and parallel to one another and second transverse partitions intersecting said second partitions and each extending in planes parallel to one another and parallel to the first direction, the first cavities each being defined by two first partitions and two first transverse partitions, the second cavities each being defined by two second partitions and two second transverse partitions, and each first partition is positioned in the continuation of a second partition in a direction intersecting the first plane and each first transverse partition is positioned in the continuation of a second transverse partition in said direction intersecting the first plane when the device is in said first position.

3. The cascade type thrust reverser device according to claim 2, wherein the second partitions of said acoustic treatment panel comprise a first end facing said thrust reverser cascade and a second end opposite to the first end, and for each second partition, and the tangent to the second partition at the second end forms a first angle with a plane parallel to said first plane when the thrust reverser device is in said first position, the first angle being comprised between 60° and 120°.

4. The cascade type thrust reverser device according to claim 3, wherein the first partitions of said thrust reverser cascade comprise a first end facing said acoustic treatment panel and a second end opposite to the first end, and for each first partition (82), and the tangent to the first partition at the first end of the first partition forms a second angle with the tangent to the second partition at the first end of the second partition when the thrust reverser device is in said first position, the second angle being comprised between −20° and +20°.

5. The cascade type thrust reverser device according to claim 2, wherein the first partitions of the cascade comprise a first curvature in the direction orthogonal to the first plane and the second partitions of the acoustic treatment panel comprise a second curvature in the direction orthogonal to the first plane distinct from the first curvature, the acoustic treatment cells formed in the first position of the thrust reverser device comprising two undulated walls orthogonal to the first direction and each formed by a first partition and a second partition in the continuation of one another.

6. The cascade type thrust reverser device according to claim 1, wherein the first cavities and the second cavities have the same shape in a section plane parallel to said first plane.

7. The cascade type thrust reverser device according to claim 1, wherein the casing also comprises a porous interface with a thickness comprised between 0.5 mm and 20 mm, formed of at least one layer of porous material and positioned at the interface between said acoustic treatment panel and said cascade when the thrust reverser device is in the first position, the thickness extending in a direction perpendicular to said first plane.

8. The cascade type thrust reverser device according to claim 1, wherein the acoustic treatment cells have a height comprised between 10 mm and 100 mm in a direction perpendicular to the first plane.

9. The cascade type thrust reverser device according to claim 1, wherein the casing comprises a perforated wall and an acoustically reflecting wall each extending parallel to said first plane, the cascade and the acoustic treatment panel being positioned between the perforated wall and the acoustically reflecting wall when the thrust reverser device is in the first position.

10. The cascade type thrust reverser device according to claim 9, wherein said perforated wall is directly assembled by gluing to said cascade or to said acoustic treatment panel.

11. The cascade type thrust reverser device according to claim 9, wherein the acoustic treatment panel is positioned between the perforated wall and the thrust reverser cascade when the thrust reverser device is in the first position.

12. The cascade type thrust reverser device according to claim 9, wherein the acoustic treatment panel is positioned between the acoustically reflecting wall and the thrust reverser cascade when the thrust reverser device is in the first position.

13. The device according to one of claims claim 1, wherein the cascade is movable and the casing is fixed.

14. The device according to onc of claims claim 1, wherein the cascade is fixed and the casing is movable.

15. A turbomachine intended to be mounted on an aircraft, the turbomachine comprising an axially symmetrical nacelle defining an axial direction and a radial direction, the nacelle including a thickness in the radial direction and a housing extending in the axial direction in its thickness to accommodate a cascade of a cascade type thrust reverser device, wherein it comprises a cascade type thrust reverser device according to claim 14, the cascade being positioned, when the thrust reversal is not required, in the corresponding housing of the nacelle of the turbomachine

16. An aircraft comprising at least one turbomachine according to claim 15.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The invention will be better understood upon reading performed hereafter, by way of indication and without limitation, with reference to the appended drawings in which:

[0050] FIGS. 1A and 1B, already described, show schematic section views in a longitudinal plane of a turbomachine according to a first known embodiment of the prior art, respectively in a position in which the thrust reversal is inactive and in a position in which the thrust reversal is activated.

[0051] FIGS. 2A and 2B, already described, show schematic section views in a longitudinal plane of a turbomachine according to a second known embodiment of the prior art, respectively in a position in which the thrust reversal is inactive and in a position where the thrust reversal is activated.

[0052] FIG. 3 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is inactive according to a first embodiment of the invention.

[0053] FIG. 4 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is activated according to a first embodiment of the invention.

[0054] FIG. 5 illustrates schematically a section view in a plane comprising the axial direction and the circumferential direction of a cascade of the thrust reverser device.

[0055] FIG. 6 illustrates schematically a section view in a plane comprising the axial direction and the circumferential direction of an acoustic treatment panel of the thrust reverser device.

[0056] FIG. 7 shows a schematic section view in a plane comprising the axial direction and the radial direction of a thrust reverser device in a position in which the thrust reversal is inactive according to a second embodiment of the invention.

[0057] FIG. 8 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is activated according to a second embodiment of the invention.

[0058] FIG. 9 is a zoom of FIG. 7 illustrating the arrangement of the first partitions and the second partitions in the first position of the device.

[0059] FIG. 10 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is inactive according to a third embodiment of the invention.

[0060] FIG. 11 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is activated according to a third embodiment of the invention.

[0061] FIG. 12 is a zoom of FIG. 10 illustrating the arrangement of the first partitions an of the second partitions in the first position of the device.

[0062] FIG. 13 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which thrust reversal is inactive according to a fourth embodiment of the invention.

[0063] FIG. 14 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is activated according to a fourth embodiment of the invention.

[0064] FIG. 15 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is in active according to a fifth embodiment of the invention.

[0065] FIG. 16 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is activated according to a fifth embodiment of the invention.

[0066] FIG. 17 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which thrust reversal is inactive according to a sixth embodiment of the invention.

[0067] FIG. 18 shows a schematic section view in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device in a position in which the thrust reversal is activated according to a sixth embodiment of the invention.

DESCRIPTION OF THE EMBODIMENTS

[0068] In FIGS. 3 to 12, the turbomachine 1 comprises a thrust reverser device 70 which can operate according to the operation described in FIGS. 2A and 2B. The turbomachine comprises a nacelle with axial symmetry around an axis X defining an axial direction D.sub.A, a radial direction D.sub.R and a circumferential direction D.sub.C.

[0069] Shown in FIGS. 3 and 4 are schematic section views in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device mounted on an aircraft turbomachine according to a first embodiment of the invention and respectively in a position in which the thrust reversal is inactive and in a position in which the thrust reversal is activated.

[0070] The thrust reverser device 70 comprises a plurality of cascades 80 assembled to form a cascade ring. The ring can have a cylindrical base or a polygonal base, the cascades 80 extending respectively either in a curved plane comprising the axial direction D.sub.A and the circumferential direction D.sub.C of the turbomachine, or in a straight plane comprising the axial direction D.sub.A and a direction tangent to the circumferential direction D.sub.C.

[0071] In the embodiments illustrated, the cascades 80 are curved to facilitate the explanation and the labels, and extend mainly in a curved plane, hereafter called the first plane, comprising the axial direction D.sub.A and the circumferential direction D.sub.C.

[0072] As shown in FIG. 5, which is a section view of a cascade 80 in a section plane parallel to the first plane, each cascade 80 comprises a frame 81 inside which extend first partitions 82 in the circumferential direction D.sub.C and first transverse partitions 83 in the axial direction D.sub.A. The frame 81, the first partitions 82 and the first transverse partitions 83 have a height in the radial direction D.sub.R comprised between 5 mm and 50 mm.

[0073] The thickness of the first partitions 82 is comprised between 0.5 mm and 5 mm to be sufficiently thick to withstand the loads to which they are subjected, but also as thin as possible to minimize the mass and the head losses in the cascade.

[0074] The first partitions 82 are azimuthal partitions intended to orient the gas flow F toward the outside of the nacelle 2 and upstream of the turbomachine 1 for the reversal of thrust when the thrust reverser device is activated. The first transverse partitions 83 are axial partitions intended to define, with the first partitions 82, first cavities 84 for the absorption of acoustic waves generated by the turbomachine, when the thrust reverser device is inactive.

[0075] The distance in the circumferential direction D.sub.C separating two first transverse partitions 83 adjacent to one another is equal to the distance in the axial direction D.sub.A separating two first partitions 82, to thus favor acoustic propagation in plane waves inside the cavities.

[0076] The cascade 80 comprises, in the axial direction D.sub.A of the turbomachine 1 on which the device 70 is mounted, a first axial end 810 and a second axial end 812. As illustrated in FIGS. 3 and 4, in the embodiments illustrated in FIGS. 3 to 12 and being able to operate according the operation described in FIGS. 2A and 2B, the second axial end 812 of the cascades 80 is fixed to a downstream portion 22 of the nacelle 2 movable with respect to an upstream portion 21 of the nacelle 2.

[0077] Housed in the upstream portion 21 of the nacelle 2 of the turbomachine 1, the thrust reverser device 70 comprises a plurality of casings 71 assembled to form a panel ring. The ring can have a cylindrical base or a polygonal base, the casings 71 extending respectively either in a curved plane comprising the axial direction D.sub.A and the circumferential direction D.sub.C of the turbomachine 1, or in a straight plane comprising the axial direction D.sub.A and a direction tangent to the circumferential direction D.sub.C.

[0078] In the embodiments illustrated, the casing's 71 are curved to facilitate the explanation and the labels, and extend mainly in a curved plane comprising the axial direction D.sub.A and the circumferential direction D.sub.C.

[0079] Each casing 71 includes a perforated wall 72, an acoustically reflecting wall 73 and an acoustic treatment panel 74. The casing 71 comprises successively in the radial plane D.sub.R moving away from the axis of revolution of the turbomachine 1, the perforated wall 72, the acoustic treatment panel 74, a housing 75 configured to accommodate the cascade 80, and the acoustically reflecting wall 73.

[0080] The casing 71 also comprises an opening 76 communicating with the housing 75, the opening extending in a plane comprising the radial direction D.sub.R and the circumferential direction D.sub.C at an axial end of the casing 71 facing the downstream portion 22 of the nacelle 2.

[0081] When thrust reversal is inactive, the thrust reverser device 70 is in a first position illustrated in FIG. 3 in which the cascade 80 is positioned in the housing 75 of the casing 71.

[0082] When thrust reversal is activated, the thrust reverser device 70 is in a second position illustrated in FIG. 4 in which the cascade 80 is extracted from the casing 71 in the axial direction D.sub.A in translation with the downstream portion 22 of the nacelle, leaving the housing 75 free, at least in part.

[0083] The acoustic treatment panel 74 is positioned in the casing 71 in a second plane parallel to the first plane in which the cascade 80 extends, and the acoustic panel 74 glued to the perforated wall 72.

[0084] The acoustic treatment panel 74 of each casing 71 comprises second partitions 742 and second transverse partitions.

[0085] As shown in FIG. 6, which is a section view of an acoustic treatment panel 74 in a section plane parallel to the first plane, each acoustic treatment panel 74 comprises a frame 741 inside which extend second partitions 742 in the circumferential direction D.sub.C and second transverse partitions 743 in the axial direction D.sub.A.

[0086] The second partitions 742 are azimuthal partitions and the second transverse partitions 743 are axial partitions. The second partitions 742 and the second transverse partitions 743 define between them second cavities 744 for the absorption of acoustic waves generated by the turbomachine, when the thrust reverser device is in its first position.

[0087] The distance in the circumferential direction D.sub.C separating two second transverse partitions 743 adjacent to one another is equal to the distance in the axial direction D.sub.A separating two second partitions 742, to thus favor acoustic propagation in plane waves inside the cavities.

[0088] In addition, at the interface between the acoustic treatment panel 71 and the cascade 80, each casing 70 comprises a porous interface 77 formed of several layers of porous material and having a thickness E in the radial direction D.sub.R comprised between 0.5 mm and 20 mm to improve the interface between the two cellular structures by ensuring better sealing between the different partitions while still facilitating the sliding of the cascade 80 in the housing 75 during translations.

[0089] When the thrust reverser device 70 is in its first position, as illustrated in FIG. 3, the first cavities 84, the first partitions 82 and the first transverse partitions 83 are superimposed respectively with the second cavities 744, the second partitions 742 and the second transverse partitions 743, and thus form resonant cavities 710, or acoustic treatment cells, the volume of each of which corresponds to the sum of the volume of a first cavity 84 and the volume of a second cavity 744. The acoustic treatment cells 710 thus extend at a height H in the radial direction D.sub.R corresponding to the sum of the height of the acoustic treatment panel 74, the thickness E of the porous interface 77 and the height of the cascade 80. The height H of the acoustic treatment cells is comprised between 10 mm and 100 mm.

[0090] In the first embodiment illustrated in FIGS. 3 and 4, the first cavities 84 and the second cavities 744 have an identical shape in a section plane comprising the axial direction D.sub.A and the circumferential direction D.sub.C, with first partitions 82 and second partitions 742 each extending purely radially. Thus, in the first position of the thrust reverser device 70, each of the first transverse partitions 83 is not only in the continuation of one of the second transverse partitions 743, but more precisely is aligned with one of the second transverse partitions 743.

[0091] Shown in FIGS. 7 and 8 are schematic section views in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device 70 mounted on an aircraft turbomachine according to a second embodiment of the invention and respectively in a position in which the thrust reversal is inactive and in a position in which the thrust reversal is activated.

[0092] The thrust reverser device 70 of the second embodiment illustrated in FIGS. 7 and 8 differs from the first embodiment illustrated in FIGS. 3 and 4 in that the first transverse partitions 83 of the cascade 80 and the second transverse partitions 743 of the acoustic treatment panel 70 each have a curvature in a section plane comprising the radial direction D.sub.R and the axial direction D.sub.A unlike the first embodiment where the partitions are rectilinear in the radial direction D.sub.R, i.e. where they extend radially.

[0093] As illustrated in FIG. 9, which is a zoom of FIG. 7 illustrating the arrangement of the first partitions 82 and of the second partitions 742 in the first position of the thrust reverser device 70 in the second embodiment, the curvature of the second partitions 742 of the acoustic treatment panel 74 is shown in FIG. 9 by a first curve C1, and the curvature of the first partitions 82 of the cascade 80 is shown by a second curve C2.

[0094] If it is considered that each partition 742 and 82 is formed by the radial stacking of an infinity of cross sections, taken in a plane orthogonal to the radial direction D.sub.R, it is possible to define a curve passing through the center of each cross section and extending over the entire height H of the acoustic treatment cell 710 which is formed by the assembly of the first curve C1 with the second curve C2 over the height H of the acoustic treatment cell 7.

[0095] The second partitions 742 of the acoustic treatment panel 74 comprise a first end 7420 facing said thrust reverser cascade 80 and a second end 7425 opposite to the first end 7420 and facing the porous wall 72.

[0096] And the first partitions 82 of the cascade 80 each comprise a first end 820 facing the acoustic treatment panel 74 and a second end 825 opposite to the first end 820 and facing the acoustically reflecting wall 73.

[0097] The second end 7425 of the second partitions 742 is thus at the inlet of the acoustic treatment cell 710.

[0098] In addition, for each second partition 742, in a section plane comprising the axial direction D.sub.A and the radial direction D.sub.R, the tangent T11 to the second partition 742 taken at the second end 7425 forms a first angle A with a plane parallel to said first plane comprised between 60° and 120°, the perforated wall 72 extending in said first plane to the second end 7425 of the second partition 742.

[0099] This orientation of the second partitions 742 of the acoustic treatment panel 74 at their second end 7425, which faces the flow circulating inside the nacelle, allows defining a substantially radial orientation of the acoustic treatment cells 710, to avoid penalizing the operation of the resonator due to undesired acoustic reflections on the partitions.

[0100] The second partitions 742 of the acoustic treatment panel are therefore curved. The use of curved second partitions 742 in the acoustic treatment panel 74 allows maximizing the effectiveness of the acoustic treatment without degrading the functionality of thrust reversal of the cascade regardless of the positioning of the panel with respect to the cascade in the direction orthogonal to the first plane.

[0101] In addition, for each first partition 82, in a section plane comprising the axial direction D.sub.A and the radial direction D.sub.R, the tangent T2 to the first partition 82 at its first end 820 forms a second angle B with the tangent T1 to the second partition 742 at the first end 7420 when the thrust reverser device 70 is in said first position. The second angle B is comprised between −20° and +20°.

[0102] The first curve C1 defines a first angle A with the first plane. The first angle A is formed between the first plane and the tangent to the end of the first curve C1 opposite to the end facing the second curve C2.

[0103] This orientation of the first partitions 82 of the thrust reverser cascade 80 and of the second partitions 742 at the location where they face one another, i.e. at the interface between the cascade and the panel 74, allowing having continuity of the acoustic treatment cells 710 and thus avoid penalizing the operation of the resonator due to undesired acoustic reflections on the partitions, without perturbing the functionality of thrust reversal.

[0104] The first partitions 82 of the thrust reverser cascade 80 all having the same shape and the second partitions 742 of the acoustic treatment panel 74 also all having the same shape, the acoustic treatment cells 710 all have the same profile, this profile following the profile of the first and second partitions 82 and 742.

[0105] The first and second curves C1 and C2 define the second angle B. The second angle B is formed between the tangent to the first curve C1 at the end of the first curve C1 facing the second curve C2 and the tangent to the second curve C2 at the end of the second curve C2 facing the first curve C1.

[0106] In FIGS. 10 and 11 are shown schematic section views in a plane comprising the axial direction and the radial direction of a cascade type thrust reverser device 70 mounted on an aircraft turbomachine 14 according to a third embodiment of the invention and respectively in a position in which the thrust reversal is inactive and in a position in which the thrust reversal is activated.

[0107] The thrust reverser device 70 of the third embodiment illustrated in FIGS. 10 and 11 differs from the second embodiment illustrated in FIGS. 7 and 8 in that the positions in the radial direction D.sub.R of the acoustic treatment panel 74 and of the cascade 80 are reversed.

[0108] In the third embodiment, the cascade 80 is, in the radial direction D.sub.R, inside the acoustic treatment panel 74. Thus, in the first position of the thrust reverser device 70 illustrated in FIG. 10, the cascade 80 extends in the radial direction D.sub.R between the perforated wall 72 of the casing 71 and the acoustic treatment panel 74, the porous interface 77 extending between the panel 74 and the cascade 80 in the radial direction D.sub.R.

[0109] As for the second embodiment, the first transverse partitions 83 of the cascade 80 and the second transverse partitions 743 of the acoustic treatment panel 70 each have a curvature in a section plane comprising the radial direction D.sub.R and the axial direction D.sub.A.

[0110] As illustrated in FIG. 12, which is a zoom of FIG. 10 illustrating the arrangement of the first partitions 82 and of the second partitions 742 in the first position of the thrust reverser device 70 in the second embodiment, the curvature of the second partitions 742 of the acoustic treatment panel 74 is shown in FIG. 12 by a first curve C1, and the curvature of the first partitions 82 of the cascade 80 is shown by a second curve C2.

[0111] If it is considered that each partitions 742 and 82 is formed by the radial stacking of an infinity of cross sections, taken in a plane orthogonal to the radial direction D.sub.R, it is possible to define a curve passing through the center of each cross section and extending over the entire height H of the acoustic treatment cell 710 which is formed by the assembly of the first curve C1 with the second curve C2 to the height H of the acoustic treatment cell 7.

[0112] The second partitions 742 of the acoustic treatment cell 74 comprise a first end 7420 facing said thrust reverser cascade 80 and a second end 7425 opposite to the first end 7420 and facing the acoustically reflecting wall 73.

[0113] And the first partitions 82 of the cascade 80 each comprise a first end 820 facing the acoustic treatment panel 74 and a second end 825 opposite to the first end 820 and facing the porous wall 72.

[0114] The second end 825 of the first partitions 82 is thus at the inlet of the acoustic treatment cell 710.

[0115] In addition, for each second partition 742, in a section plane comprising the axial direction D.sub.A and the radial direction D.sub.R, the tangent T11 to the second partition 742 taken at the second end 7425 forms a first angle A with a plane parallel to said first plane comprised between 60° and 120°, the acoustically reflecting wall 73 extending in said first plane to the second end 7425 of the second partition 742.

[0116] The first curve C1 defines the first angle A with the first plane. The first angle A is formed between the first plane and the tangent to the end of the first curve C1 opposite to the end facing the second curve C2.

[0117] This orientation of the second partitions 742 of the acoustic treatment panel 74 at their second end 7425 allows defining a substantially radial orientation of the acoustic treatment cells 710, to avoid penalizing the operation of the resonator due to undesired acoustic reflections on the partitions.

[0118] In addition, for each first partition 82, in a section plane comprising the axial direction D.sub.A and the radial direction D.sub.R, the tangent T2 to the first partition 82 at its first end 820 forms a second angle B with the tangent T1 to the second partition 742 at the first end 7420 when the thrust reverser device 70 is in said first position. The second angle B is comprised between −20° and +20°.

[0119] The first and second curves C1 and C2 define the second angle B. the second angle B is formed between the tangent to the first curve C1 at the end of the first curve C1 facing the second curve C2 and the tangent to the second curve C2 at the end of the second curve C2 facing the first curve C1.

[0120] In FIGS. 13 to 18, the turbomachine 1 comprises in this case a thrust reverser device 70 which can operate according to the operation described in FIGS. 1A and 1B.

[0121] In FIGS. 13 and 14 are shown schematic section views in a plane comprising the axial direction D.sub.A and the radial direction D.sub.R of a cascade type thrust reverser device mounted on an aircraft turbomachine 1 according to a fourth embodiment of the invention and respectively in a position in which the thrust reversal is inactive and in a position in which the thrust reversal is activated.

[0122] The fourth embodiment differs from the first embodiment in that the cascade 80 is secured to the upstream portion 21 of the nacelle 2 of the turbomachine 1 and the casing 71 is made in the downstream portion 22 of the nacelle 2. Thus, as illustrated in FIGS. 14, 16 and 18, in the embodiments illustrated in FIGS. 13 to 18 and being able to operate according to the operation described in FIGS. 1A and 1B, the first axial end 810 of the cascades 80 is fixed to an upstream portion 21 of the nacelle 2, movable with respect to a downstream portion 22 of the nacelle 2.

[0123] The casing 71 comprises an opening 76 communicating with the housing 75, the opening extending in a plane comprising the radial direction D.sub.R and the circumferential direction D.sub.C at an axial end of the casing 71 facing the upstream portion 21 of the nacelle 2.

[0124] When the thrust reversal is inactive, the thrust reverser device 70 is in a first position illustrated in FIG. 13 in which the cascade 80 is positioned in the housing 75 of the casing 71.

[0125] When the thrust reversal is activated, the thrust reverser device 70 is in a second position illustrated in FIG. 14 in which the cascade 80 is extracted from the casing 71 in the axial direction DA, the casing 71 being in translation with the downstream portion 21 of the nacelle 2, leaving the housing 75 at least partially free.

[0126] Shown in FIGS. 15 and 16 are schematic section views in a plane comprising the axial direction D.sub.A and the radial direction D.sub.R of a cascade type thrust reverser device mounted on an aircraft turbomachine 1 according to a fifth embodiment of the invention and respectively in a position in which the thrust reversal is inactive and in a position in which the thrust reversal is activated.

[0127] The fifth embodiment differs from the second embodiment in that the cascade 80 is secured to the upstream portion 21 of the nacelle 2 of the turbomachine 1 and the casing 71 is made in the downstream potion 22 of the nacelle 2.

[0128] Shown in FIGS. 17 and 18 are schematic section views in a plane comprising the axial direction D.sub.A and the radial direction D.sub.R of a cascade type thrust reversal device mounted on an aircraft turbomachine 1 according to a sixth embodiment of the invention and respectively in a position in which the thrust reversal is inactive and in a position in which the thrust reversal is activated.

[0129] The sixth embodiment differs from the third embodiment in that the cascade 80 is secured to the upstream portion 21 of the nacelle 2 of the turbomachine 1 and the casing 71 is made in the downstream portion 22 of the nacelle 2.

[0130] The invention thus supplies a cascade type thrust reverser device which allows both reorienting an air flow upstream of the turbomachine outside the nacelle and minimizing the head losses through the cascade when the thrust reversal is activated, and maximizing the effectiveness of acoustic absorption when the thrust reversal is inactive.