Patent ID: 12241433

DETAILED DESCRIPTION

FIGS.1and2illustrate an aft section of a propulsion system20for an aircraft such as, but not limited to, a commercial airliner or cargo plane. This aircraft propulsion system20includes a nacelle22and a gas turbine engine (not visible inFIGS.1and2). The gas turbine engine may be configured as a turbojet gas turbine engine or a turbofan gas turbine engine; however, the present disclosure is not limited to such exemplary engine configurations.

The nacelle22is configured to house and provide an aerodynamic cover for the gas turbine engine. The nacelle22extends axially along an axial centerline24(e.g., a station line26) of the aircraft propulsion system20to a downstream, aft end28of the nacelle22. The nacelle22ofFIGS.1and2includes a nacelle aft structure30(a structure of the aircraft propulsion system20) configured with a thrust reverser system32. This thrust reverser system32is configured as a pivoting door thrust reverser system. More particularly, the thrust reverser system32may be configured as a target-type thrust reverser system. The term “target-type” may describe a pivoting door thrust reverser system that redirects a hot gas stream (e.g., a core gas stream) exhausted from the gas turbine engine, or both an outer cold gas stream (e.g., a bypass gas stream) and an inner hot gas stream (e.g., a core gas stream) exhausted from the gas turbine engine. It is contemplated, however, the thrust reverser system32may alternatively be configured as a clamshell-type thrust reverser system. The term “clamshell-type” may describe a pivoting door thrust reverser system that redirects an outer cold gas stream exhausted from the gas turbine engine, but not an inner hot gas stream exhausted from the gas turbine engine.

The aft structure30ofFIGS.1and2includes a fixed structure34and one or more (e.g., an opposing pair of) thrust reverser doors36A and36B (generally referred to as “36”). The aft structure30may also include (or may be configured without) one or more cascade structures38.

Referring toFIG.1, the aft structure30and its components (e.g.,34and36) are configured to form an aft portion of an outer aerodynamic flow surface40of the nacelle22. The aft structure30and its components (e.g.,34and36) are configured to form an aft portion of an inner aerodynamic flow surface42of the nacelle22. This aft portion of the inner aerodynamic flow surface42forms an outer peripheral boundary of an aft-most portion of a flowpath44within the aircraft propulsion system20. This aft-most portion of the flowpath44receives a gas flow (e.g., core gas and/or bypass air) from the upstream gas turbine engine. The aft-most portion of the flowpath44extends axially along the axial centerline24within the aircraft propulsion system20and its aft structure30to an annular trailing edge46of an exhaust nozzle48, at which point the flowpath44ofFIG.1meets an exterior environment50surrounding the aircraft propulsion system20. This exhaust nozzle48may be at least partially or completely formed by an aft portion52of the fixed structure34(or another standalone nozzle structure). With such an arrangement, the thrust reverser system32may be termed a “pre-exit” thrust reverser system. Alternatively, referring toFIGS.3and4, the exhaust nozzle48may be at least partially or completely formed by the thrust reverser doors36. With such an arrangement, the thrust reverser system32may be termed a “post-exit” thrust reverser system. While the disclosure herein may be applicable to both pre-exit and post-exit thrust reverser systems, the thrust reverser system32is described below with respect to the pre-exit thrust reverser system (e.g., a pre-exit pivoting door thrust reverser system) for ease of description.

The fixed structure34ofFIG.1extends axially along the axial centerline24to a downstream, aft end of the fixed structure34. The fixed structure34extends radially between and to a radial inner side54of the fixed structure34and a radial outer side56of the fixed structure34. The structure inner side54may partially form the inner aerodynamic flow surface42. The structure outer side56may partially form the outer aerodynamic flow surface40. The fixed structure34extends circumferentially about (e.g., completely around) the axial centerline24, thereby providing the fixed structure34with, for example, a tubular body.

The thrust reverser doors36are arranged circumferentially about the axial centerline24. More particularly, the thrust reverser doors36ofFIGS.1and2are arranged on (e.g., diametrically) opposing sides of the thrust reverser system32and the flowpath44. Referring toFIGS.5and6, the thrust reverser doors36may be moveably attached to the fixed structure34. Each thrust reverser door36A,36B, for example, may be pivotally attached to the fixed structure34by one or more hinges58A,58B (generally referred to as “58”). Each hinge58A,58B has a hinge line60A,60B (generally referred to as “60”). The hinge line(s)60A,60B of the hinge(s)58A,58B for a respective one of the thrust reverser doors36A,36B form a pivot axis62A,62B (generally referred to as “62”) for that thrust reverser door36A,36B. Each thrust reverser door36may pivot about its respective pivot axis62between a stowed, closed position (e.g., seeFIGS.1and5) and a deployed, open position (e.g., seeFIGS.2and6).

Each thrust reverser door36may be pivoted between its stowed position and its deployed position by one or more dedicated actuators; e.g., linear actuators such as hydraulic cylinders, leadscrews, etc. Alternatively, the thrust reverser system32may include one or more common actuators to pivot the thrust reverser doors36between their stored positions and their deployed positions.

Each thrust reverser door36A,36B may have an arcuate (e.g., partially conical) body. For example, when in the stowed position ofFIG.1(see alsoFIG.5), each of the thrust reverser doors36A,36B extends axially along the axial centerline24between a forward end64A,64B (generally referred to as “64”) (e.g., leading edge) of the respective thrust reverser door36A,36B and an aft end66A,66B (generally referred to as “66”) (e.g., trailing edge) of the respective thrust reverser door36A,36B. Each of the thrust reverser doors36A,36B extends radially between and to a radial inner side68A,68B (generally referred to as “68”) of the respective thrust reverser door36A,36B and a radial outer side70A,70B (generally referred to as “70”) of the respective thrust reverser door36A,36B. The door inner side68A,68B may partially form the inner aerodynamic flow surface42. The door outer side70A,70B may partially form the outer aerodynamic flow surface40. Referring toFIG.6, each of the thrust reverser doors36A,36B extends circumferentially about (e.g., partially around) the axial centerline24a certain door angle between circumferentially opposing sides72A,72B (generally referred to as “72”) and74A,74B (generally referred to as “74”) of the respective thrust reverser door36A,36B.

In some embodiments, the door angle may be equal to or greater than ninety degrees (90°); e.g., between one-hundred and thirty-five degrees (135°) and one-hundred and eighty degrees (180°). In addition or alternatively, an axial length of each thrust reverser door36(between the door ends64and66; seeFIG.1) may be equal to, or within plus/minus (+/−) ten percent (10%), twenty percent (20%), thirty percent (30%) of, a circumferential width of that thrust reverser door36(between the door sides72and74; seeFIG.6). With such an arrangement, the thrust reverser system32may be configured with (e.g., only) two of the thrust reverser doors36, where one of the thrust reverser doors (e.g.,36A; a top door or alternatively a first side door) is disposed on and extends along one side of the aircraft propulsion system20/the flowpath44, and where the other one of the thrust reverser doors (e.g.,36B; a bottom door or alternatively a second side door) is disposed on and extends along the other side of the aircraft propulsion system20/the flowpath44. The present disclosure, however, is not limited to such exemplary dimensions or door arrangements.

When stowed, each of the stowed thrust reverser doors36ofFIG.1(see alsoFIG.2) may axially overlap/cover one or more thrust reverser passages76and78; e.g., a jet pipe opening76(seeFIG.2), cascade port(s)78, etc. By covering these thrust reverser passages76and78, the thrust reverser door36may generally prevent gas from flowing radially outward through the thrust reverser passages76and78from the flowpath44. The gas exhausted from the gas turbine engine may thereby flow (e.g., unobstructed) through the flowpath44and out of the aircraft propulsion system20through the exhaust nozzle48. By contrast, when deployed to the deployed position ofFIG.2(see alsoFIG.6), each thrust reverser door36pivots outward into the exterior environment50outside of the aircraft propulsion system20and downward into the flowpath44. This thrust reverser door movement uncovers outer sides of the thrust reverser passages76and78and may thereby open the thrust reverser passages76and78, where each jet pipe opening76ofFIG.2is formed by and/or extends axially between a respective one of the cascade structures38and a respective one of the thrust reverser doors36. The thrust reverser door movement also positions the thrust reverser doors36to block access to the exhaust nozzle48as well as redirect the gas flowing within the flowpath44radially outward and through the thrust reverser passages76and78.

Referring toFIGS.2and6, to increase (e.g., improve) blocking downstream access to the exhaust nozzle48and/or redirecting of gas from the flowpath44through the thrust reverser passages76and78during thrust reverser system operation, portions80A and80B (generally referred to as “80”) of the thrust reverser doors36A and36B at the aft ends66A and66B may be partially nested. The aft end portions80of the thrust reverser doors36may also or alternatively radially overlap one another. With this arrangement, the thrust reverser doors36may substantially or completely block a straight line-of-sight into an upstream portion of the flowpath44from the exhaust nozzle48. To facilitate this nesting and/or radial overlap, the pivot axis62A for the first thrust reverser door36A ofFIG.6is arranged non-parallel with the pivot axis62B for the second thrust reverser door36B. More particularly, the pivot axis62A for the first thrust reverser door36A is angularly offset from the pivot axis62B for the second thrust reverser door36B by an acute angle82when viewed in a reference plane, for example, perpendicular to the axial centerline24; e.g., a plane defined by a butt line84of the aircraft propulsion system20and a waterline86of the aircraft propulsion system20. The inter-pivot axis angle82may be greater than zero degrees (0°) and less than thirty degrees (30°); e.g., between one degree (10) and five degrees (5°), between five degrees (5°) and ten degrees (10°), etc.

Referring toFIG.6, the pivot axis62A for the first thrust reverser door36A may be angled relative to a reference line88(e.g., the butt line84) which is coincident with and perpendicular to the axial centerline24(e.g., the station line26). The pivot axis62A for the first thrust reverser door36A, for example, may be angularly offset from the reference line88by an acute angle90A. This first inter-pivot axis-reference line angle90A may be less than ninety degrees (90°) and greater than seventy-five degrees (75°); e.g., between seventy-five degrees (75°) and eighty degrees (80°), between eighty degrees (80°) and eighty-five degrees (85°), between eighty-five degrees (85°) and ninety degrees (90°). However, in other embodiments, the pivot axis62A for the first thrust reverser door36A may alternatively be perpendicular to the reference line88or parallel with the reference line88(depending upon how the aircraft propulsion system20is arranged with/mounted to an airframe of the aircraft).

The pivot axis62B for the second thrust reverser door36B may be angled relative to the reference line88. The pivot axis62B for the second thrust reverser door36B, for example, may be angularly offset from the reference line88by an acute angle90B. This second inter-pivot axis-reference line angle90B may be less than ninety degrees (90°) and greater than seventy-five degrees (75°); e.g., between seventy-five degrees (75°) and eighty degrees (80°), between eighty degrees (80°) and eighty-five degrees (85°), between eighty-five degrees (85°) and ninety degrees (90°). However, in other embodiments, the pivot axis62B for the first thrust reverser door36A may alternatively be perpendicular to the reference line88or parallel with the reference line88(depending upon how the aircraft propulsion system20is arranged with/mounted to the aircraft airframe). A magnitude of the second inter-pivot axis-reference line angle90B may be equal to or different (e.g., greater or less) than the first inter-pivot axis-reference line angle90A.

The aircraft propulsion system20and its thrust reverser system32may be located near (e.g., next to) a component92of the aircraft airframe such as, but not limited to, a fuselage or a wing. With such an arrangement, the pivot axes62may be angled such that the thrust reverser doors36tip/tilt away from the airframe component92. The thrust reverser doors36may thereby direct an efflux of the gas out of the flowpath44and away from the airframe component92.

In some embodiments, referring toFIGS.1and2, the pivot axes62may be axially offset from one another along the axial centerline24. The pivot axes62, more particularly, may be arranged at different locations along the station line26. In other embodiments, referring toFIG.7, the pivot axes62may be axially aligned along the axial centerline24. The pivot axes62, more particularly, may be arranged at a common location along the station line26.

In some embodiments, referring toFIG.8, the pivot axis62A for the first thrust reverser door and/or the pivot axis62B for the second thrust reverser door may each be arranged perpendicular to the axial centerline24. In other embodiments, referring toFIG.9, the pivot axis62A for the first thrust reverser door and/or the pivot axis62B for the second thrust reverser door may each angularly offset from the axial centerline24by a respective acute angle94A,94B (generally referred to as “94”). This inter-pivot axis-axial centerline angle94may be less than ninety degrees (90°) and greater than seventy-five degrees (75°); e.g., between seventy-five degrees (75°) and eighty degrees (80°), between eighty degrees (80°) and eighty-five degrees (85°), between eighty-five degrees (85°) and ninety degrees (90°).

In some embodiments, the thrust reverser doors36may pivot a common number of degrees about their pivot axes62between the stowed and the deployed positions. In other embodiments, however, one of the thrust reverser doors36may pivot a larger number of degrees about its pivot axis62between the stowed and the deployed positions than the other one of the thrust reverser doors36. By opening one of the thrust reverser doors36more than the other one of the thrust reverser doors36, it may be possible to mitigate vectored leakage through a gap between the deployed (e.g., opened) thrust reverser doors36; e.g., see gap96inFIG.10.

While various embodiments of the present invention have been disclosed, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the invention. For example, the present invention as described herein includes several aspects and embodiments that include particular features. Although these features may be described individually, it is within the scope of the present invention that some or all of these features may be combined with any one of the aspects and remain within the scope of the invention. Accordingly, the present invention is not to be restricted except in light of the attached claims and their equivalents.