Aircraft propulsion assembly with jet engine, pylon and fire extinguishing system

Abstract

The invention relates to a propulsion assembly (100) for an aircraft (50), the propulsion assembly (100) having: a jet engine (102); -an attachment pylon (104) having a rigid structure (106); and-a fire extinguishing system (2). According to the invention, the fire extinguishing system is located in a forward position relative to the rigid structure, the fire extinguishing system being positioned between the rigid structure and the jet engine. Through the arrangement, the length of the pipeline of the fire extinguishing agent between the fire extinguishing bottle and the nozzle can be reduced, and the total weight of the fire extinguishing system is reduced.

Description

Technical Field

[0001] The present invention relates to the general field of aircraft propulsion assemblies. In particular, the present invention relates to a fire extinguishing system implemented in a propulsion assembly. The present invention also relates to an aircraft equipped with such a propulsion assembly. Background Art

[0002] Prior art propulsion assemblies are secured beneath the wing of an aircraft having a jet engine and an attachment pylon via which the jet engine is secured beneath the wing.

[0003] Due to the design of the prior art attachment pylons, standard fire extinguishing systems are mounted at the rear of the attachment pylons, above the aerodynamic fairing of the attachment and below the wing. They are usually connected to the rigid structure of the pylon or the inner camber of the wing. Since the extinguishing agent of the fire extinguishing system needs to be directed toward the nozzle located in the fire extinguishing area, a common solution is to implement piping along the pylon from the fire extinguisher bottle position toward the nozzle. However, the fire extinguisher bottle is mounted at the rear of the rigid structure, while the nozzle is located at the front of the rigid structure, closer to the jet engine.

[0004] Therefore, the length of the pipe is quite long. As a result, a large amount of extinguishing agent in the fire extinguisher bottle is required to ensure the operation of the system. Therefore, the volume of the bottle will also be large, just like the weight of the system.

[0005] Therefore, there is a need to provide a fire extinguishing system that at least partially overcomes the above-mentioned disadvantages. Summary of the invention

[0006] An object of the present invention is to propose a propulsion assembly for an aircraft, the propulsion assembly having:

[0007] - jet engines;

[0008] - An attachment bracket with a rigid structure; and

[0009] - Fire extinguishing system.

[0010] According to the invention, the fire extinguishing system is located in a forward position relative to the rigid structure, the fire extinguishing system being positioned between the rigid structure and the jet engine.

[0011] By this arrangement, the length of the pipe from the fire extinguisher bottle to the nozzle can be reduced (as described below). Having a shorter pipe can make it possible to reduce the required volume of fire extinguishing agent and thus reduce the size and weight of the fire extinguisher bottle. In addition, having a fire extinguishing system in this area allows the fire extinguisher bottle to have cold air ventilation due to air suction from the fan.

[0012] Advantageously, the jet engine comprises a fan casing and a center casing both extending around a longitudinal axis. In addition, the rigid structure takes the form of a box having a front wall and an upper spar extending forwardly relative to the front wall. The fire extinguishing system is positioned between the upper spar, the front wall and the fan casing.

[0013] Advantageously, the fire extinguishing system comprises:

[0014] - At least one fire extinguisher bottle containing fire extinguishing agent;

[0015] - at least one nozzle positioned in a critical area of ​​the propulsion assembly; and

[0016] - pipes, each pipe having a first end connected to at least one fire extinguisher bottle and a second end connected to said at least one nozzle, for conveying a fire extinguishing agent.

[0017] Advantageously, the fire-extinguishing system comprises a support device having at least one support ring on which it is retained and removably fixed, each support ring being fixed to a base fixed to the upper spar or to the front wall.

[0018] Advantageously, the support device comprises a side panel extending generally perpendicular to the base, the side panel being fixed to the upper spar or the front wall.

[0019] Advantageously, each support ring comprises a cutout allowing said fire extinguisher bottle to be mounted and removed from the support ring.

[0020] Advantageously, each support ring comprises locking means for removably fixing one of said at least one extinguisher bottle on said support ring, said locking means being arranged to allow locking and unlocking of said extinguisher bottle on said support ring.

[0021] The invention also proposes an aircraft having a propulsion assembly according to the aforementioned variant. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and other features of the present invention will become more apparent upon reading the following description of an exemplary embodiment, which description is given with reference to the accompanying drawings, in which:

[0023] Figure 1 is a side view of an aircraft according to the present invention;

[0024] Figure 2 is a schematic diagram of a propulsion assembly according to the present invention;

[0025] Figure 3 is a perspective view of an example of a front engine attachment for use in a propulsion assembly according to the present invention;

[0026] Figure 4is a perspective view of an example of a complementary front engine attachment for use in a propulsion assembly according to the present invention;

[0027] Figure 5 yes Figure 2 Detailed view of

[0028] Figure 6 is a perspective view of a fire suppression system configured to be implemented in the propulsion assembly of the present invention. DETAILED DESCRIPTION

[0029] Figure 1 An aircraft 50 is shown having a fuselage 51 and wings 52 on each side of the fuselage 51. At least one propulsion assembly 100 is fastened under each wing 52 and it comprises a jet engine 102 and an attachment pylon 104.

[0030] By convention, X represents the longitudinal axis of the propulsion assembly 100, which corresponds to the longitudinal axis X of the jet engine 102. In addition, Y represents the lateral axis of the propulsion assembly 100, which corresponds to the transverse axis of the jet engine 102, which axis is horizontal when the aircraft is on the ground, and Z represents the vertical axis or vertical height of the propulsion assembly, which corresponds to the vertical axis of the jet engine 102, which axis is vertical when the aircraft is on the ground, and these three axes X, Y and Z are orthogonal to each other.

[0031] Furthermore, the terms "front" and "rear" are considered relative to the forward direction of movement of the aircraft when the jet engine 102 is in operation, which direction is schematically indicated by arrow 107. The jet engine 102 also has a vertical median plane P(XZ) passing through the longitudinal axis X and the vertical axis Z.

[0032] The jet engine 102 has at the front a fan casing 102a surrounding an annular fan duct in which the fan rotates, and at the rear of the fan casing 102a a center casing 102b of smaller dimensions enclosing the core of the jet engine 102. The fan casing 102a and the center casing 102b surround a longitudinal axis X.

[0033] The propulsion assembly 100 also has a nacelle 102a in which the jet engine 102 is mounted.

[0034] Figure 2 A propulsion assembly 100 is shown having a jet engine 102 and an attachment pylon 104 via which the jet engine 102 is fastened to the wing 52. The attachment pylon 104 is shown here by its rigid structure 106, also called primary structure, which is fastened below the wing 52.

[0035] The rigid structure 106 extends between the front and rear ends along the longitudinal axis X and takes the form of a box having a lower spar 106a, an upper spar 106b, two lateral walls 106c and a front wall 106d, which are fixed together to realize the rigid structure 106. The front wall 106d is oriented towards the front of the aircraft 50. The side walls 106c are provided on each side of the vertical median plane P. The upper spar 106b is above the side walls 106c and the lower spar 106a is below the side walls 106c.

[0036] The upper spar 106b extends forwardly relative to the front wall 106d, which means that the upper spar 106b has a front end in the forward direction F away from the front wall 106d.

[0037] In this embodiment, the propulsion assembly 100 comprises a reaction device 170 for reacting the thrust generated by the jet engine 102. Here, the reaction device 170 comprises two reaction rods 170a, which are arranged on either side of the median plane P and are hinged on the one hand at the front to the central housing 102b and on the other hand at the rear to the rigid structure 106, for example to the lower spar 106a, thanks to appropriate fittings, which are not described in detail since they are not part of the invention and which a person skilled in the art will be able to implement as known in the art.

[0038] In this embodiment, the propulsion assembly 100 also includes a rear attachment 180 between the rigid structure 106 and the rear upper portion of the center shell 102b, in this case, between the lower spar 106a and the rear upper portion of the center shell 102b. Since the rear attachment 180 is not part of the present invention, the rear attachment 180 is not described in detail, and a person skilled in the art will be able to implement the rear attachment by existing technology.

[0039] Propulsion assembly 100 also includes a forward engine attachment 152 secured between upper region 103 of fan case 102a and a forward end of upper spar 106b.

[0040] At the same time, the propulsion assembly 100 comprises a complementary front engine attachment 153 fixed between the upper area 105 of the central shell 102b and the lower end of the front wall 106d. With this arrangement, the size of the attachment is reduced and allows to optimize the aerodynamics by reducing the size of the fairing of the nacelle.

[0041] It should be understood that a variety of approaches may be implemented to achieve the front engine attachment 152 and the complementary front engine attachment 153. Nonetheless, examples of each of these attachments are described below.

[0042] Figure 3An exemplary embodiment of a front engine attachment 152 is shown. In this example, the front engine attachment 152 comprises a rod 154 which is hingedly mounted at a vertical mid-plane P at the front end of the upper spar 106b.

[0043] To this end, the front end of the upper spar 106b comprises, for example, a front cylindrical piece whose axis is in the vertical median plane P and parallel to the longitudinal axis X, and the rod 154 comprises a front hole into which the front cylindrical piece is inserted in an articulated manner.

[0044] On each side of the vertical median plane P, the rod 154 comprises an end 154a-b hingedly mounted on the upper zone 103 of the fan casing 102a. The two ends 154a-b are symmetrical relative to the vertical median plane P.

[0045] To this end, for each end 154a-b of the rod 154, a female clamping piece 159a-b is fixed to the upper region 103 of the fan housing 102a, and said end 154a-b of the rod 154 is a male clamping piece, which is hingedly mounted in said female clamping piece 159a-b and is held by a hinge shaft inserted into the hinge hole of the end 154a-b. The hinge hole and the hinge shaft of the female clamping piece 159a-b are parallel to the longitudinal axis X.

[0046] Figure 4 An exemplary embodiment of a complementary front engine attachment 153 is shown. In this example, the complementary front engine attachment 153 comprises two fitting components 452a-b, each of which comprises a first hinge point 454a at a vertical median plane P to enable hinge connection with the lower end of the front wall 106d, and comprises a second hinge point 454b-c on each side of the vertical median plane P to enable hinge connection with the upper area 105 of the central housing 102b.

[0047] Each fitting assembly 452a-b is entirely in a plane perpendicular to the longitudinal axis X, and each hinge point 454a-c takes the form of a pivot link whose axis of rotation is entirely parallel to the longitudinal axis X. Each hinge 454a-c of one fitting assembly 452a-b is coaxial with one hinge 454a-c of another fitting assembly 452a-b.

[0048] To this end, each hinge point 454a-c is realized by a combination of a first hinge hole 455 through the corresponding fitting component 452a-b and a second hinge hole 457 through the lower end of the front wall 106d or the upper region 105 of the central housing 102b.

[0049] In position, the first hinge hole 455 of one fitting component 452a-b is aligned with the first hinge hole 455 of the other fitting component 452b-a and the second hinge hole 457 of the lower end of the front wall 106d or the upper region 105 of the center housing 102b.

[0050] The propulsion assembly 100 further comprises an articulation shaft 459 for each second articulation hole 457, which is inserted into the second articulation hole 457 and the corresponding first articulation hole 455 of the two joint assemblies 452a-b. The axis of each articulation shaft 459 is generally parallel to the longitudinal axis X.

[0051] In this example, each fitting assembly 452a-b takes the form of a triangle, and the fitting assemblies 452a-b are arranged on each side of the lower end of the front wall 106d.

[0052] According to the specific arrangement, the front engine attachment 152 reacts only lateral loads (parallel to the lateral axis Y), while the complementary front engine attachment 153 reacts both lateral loads (parallel to the lateral axis Y) and vertical loads (parallel to the vertical axis Z).

[0053] Furthermore, due to the side loads acting on the fan case 102a and the side loads acting on the center case 102b, the axial moment Mx is maintained by the forward engine attachment 152 and the complementary forward engine attachment 153. The load transfer from the jet engine 102 to the attachment pylon 104 with this engine mounting concept is balanced.

[0054] Preferably, in order to strengthen the upper spar 106b, the propulsion assembly 100 includes a main rod 156 fixed between the upper spar 106 and the front wall 106d. Each end of the main rod 156 is respectively mounted to the upper spar 106b and the front wall 106d in a hinged manner.

[0055] Figure 2 , 5 and 6 show a propulsion assembly according to the present invention. The propulsion assembly 100 also includes a fire extinguishing system 2, which is located in a forward position relative to the rigid structure 106. The forward position is determined according to the horizontal axis X and the forward direction 107. More specifically, the fire extinguishing system 2 is positioned between the rigid structure 106 and the jet engine 102.

[0056] Preferably, the jet engine 102 comprises a fan case 102a and a center case 102b, each extending around a longitudinal axis (X), as previously described. The fan case 102a and the center case 102b have a vertical median plane P passing through the longitudinal axis X.

[0057] Furthermore, the rigid structure 106 takes the form of a box having a front wall 106d and an upper spar 106b extending forward relative to the front wall 106d. Thus, the fire extinguishing system 2 is positioned between the upper spar 106b, the front wall 106d and the fan case 102a.

[0058] Due to this new positioning of the fire extinguishing system 2, the length of the pipe from the fire extinguisher bottle 21 to the nozzle 22 can be reduced (as described below). Having a shorter pipe can make it possible to reduce the required extinguishing agent volume and thus reduce the size and weight of the fire extinguisher bottle 21.

[0059] Furthermore, having the fire extinguishing system 2 in this area allows the fire extinguishing bottles 21 to have cold air ventilation due to the air suction from the fans.

[0060] As mentioned above and as Figure 6 As shown, the fire extinguishing system 2 includes:

[0061] - at least one fire extinguisher bottle 21 containing a fire extinguishing agent;

[0062] - at least one nozzle 22 positioned in a critical fire zone of said propulsion assembly 100; and

[0063] - Pipes 23, each pipe 23 having a first end 231 connected to at least one fire extinguisher bottle and a second end 232 connected to said at least one nozzle 22, for conveying a fire extinguishing agent.

[0064] Preferably, each pipe 23 is connected between a fire extinguisher bottle 21 and a set of nozzles 22 (not shown).

[0065] Due to the positioning of the fire extinguishing system, the length of the pipe 23 is optimized, so that the overall weight of the system can also be optimized.

[0066] according to Figure 5 and 6 In the embodiment shown, the fire extinguishing system 2 comprises a support device 24 having at least one support ring 241, wherein at least one fire extinguishing bottle 21 is held and removably fixed on the support ring. Each support ring 241 is fixed to a base 242, which is fixed to the upper spar 106b or the front wall 106d.

[0067] In this example, the fire extinguishing system 2 comprises two fire extinguishing bottles 21, but it is clear that one bottle or more than two bottles 21 can be implemented without departing from the general principle of the invention. It is understood that the number of support rings 241 will therefore be adapted to the number of bottles 21.

[0068] Each fire extinguisher bottle 21 is held on the support ring 241. This means that the fire extinguisher bottle 21 is received in the support ring 241, or the fire extinguisher bottle 21 is arranged on the support ring 241. In other words, each fire extinguisher bottle 21 is supported by the support ring 241.

[0069] like Figure 5 and 6 As shown, the base 242 is fixed to the front wall 106d of the rigid structure 106. Thus, the base 242 extends generally vertically, which means that it is generally parallel to the vertical axis Z. Thus, the fire extinguisher bottles 21 are generally vertically aligned one above the other.

[0070] In a variant not shown, the base 242 is fixed to the upper spar 106b of the rigid structure 106. The base 242 thus extends generally horizontally, which means that it is generally parallel to the horizontal axis X. The extinguisher bottles 21 are thus aligned generally horizontally adjacent to one another.

[0071] In this manner, the fire suppression system 2 is positioned close to the critical fire area (that is, close to the jet engine 102 ) and is securely secured to the rigid structure 106 .

[0072] according to Figure 5 and 6 In the particular embodiment shown, the support device 24 includes a side panel 243 extending generally perpendicular to the base 242. The side panel 243 is fixed to the upper spar 106b or the front wall 106d. More specifically, when the base 242 is fixed to the front wall 106d, the side panel 243 is thus fixed to the upper spar 106b (as shown). When the base 242 is fixed to the upper spar 106b, the side panel 243 is thus fixed to the front wall 106d (not shown).

[0073] The side panels 243 serve as reinforcements to ensure that the fire extinguishing system 2 is securely fixed to the rigid structure 106 .

[0074] Preferably, each support ring 241 includes a cutout 241a that allows the fire extinguisher bottle 21 to be mounted on and removed from the support ring 241. More specifically, each support ring 241 surrounds at least a portion of the fire extinguisher bottle 21 held in the support ring 241. The cutout 241a allows the fire extinguisher bottle 21 to be mounted on and removed from the support ring 241 by movement of the fire extinguisher bottle 21 relative to the support ring 241 parallel to the horizontal plane XY. In other words, the fire extinguisher bottle 21 can be mounted on and removed from the support ring by lateral movement of the fire extinguisher bottle 21.

[0075] Specifically, the fire extinguishing system 2 is designed and fixed to the rigid structure 106 in such a way that the fire extinguishing bottle 21 can be installed on the side of the propulsion assembly 100 and removed from the propulsion assembly 100 (e.g., for maintenance or refilling operations). Therefore, the installation and removal operations of the fire extinguishing bottle 21, and more generally the installation and removal operations of the fire extinguishing system 2 are facilitated.

[0076] Preferably, each support ring 241 comprises a locking device 25 for removably fixing one of the at least one fire extinguisher bottle 21 on the support ring 241. The locking device 25 is arranged to allow locking and unlocking of the fire extinguisher bottle 21 on the support ring 241. Thus, each fire extinguisher bottle 21 is removably fixed to the support ring 241 due to the removable locking device 25. The removable locking device 25 may, for example, take the form of a bolt or a quick release fastener.

Claims

1. A propulsion assembly (100) for an aircraft (50), the propulsion assembly (100) comprising: - jet engine (102); - an attachment bracket (104) having a rigid structure (106); and - Fire extinguishing system (2); in, The fire extinguishing system (2) is located in a forward position relative to the rigid structure (106), and the fire extinguishing system (2) is positioned between the rigid structure (106) and the jet engine (102).

2. The propulsion assembly (100) according to claim 1, characterized in that - the jet engine (102) comprises a fan casing (102a) and a center casing (102b) both extending around a longitudinal axis (X), - the rigid structure (106) is in the form of a box having a front wall (106d) and an upper spar (106b) extending forwardly relative to the front wall (106d), And wherein the fire extinguishing system (2) is positioned between the upper spar (106b), the front wall (106d) and the fan casing (102a).

3. The propulsion assembly (100) according to claim 1 or 2, characterized in that: The fire extinguishing system (2) comprises: - at least one fire extinguisher bottle (21) containing a fire extinguishing agent; - at least one nozzle (22) positioned in a critical fire zone of said propulsion assembly (100); and - Pipes (23), each pipe (23) having a first end (231) connected to the at least one fire extinguisher bottle and a second end (232) connected to the at least one nozzle (22), for conveying a fire extinguishing agent.

4. The propulsion assembly (100) according to claim 3, characterized in that The fire extinguishing system (2) comprises a supporting device (24), the supporting device (24) having at least one supporting ring (241), the at least one fire extinguisher bottle (21) being held and removably fixed on the supporting ring, each supporting ring (241) being fixed to a base (242), the base (242) being fixed to the upper spar (106b) or the front wall (106d).

5. The propulsion assembly (100) according to claim 4, characterized in that The support device (24) comprises a side panel (243) extending generally perpendicular to the base (242), the side panel (243) being fixed to the upper spar (106b) or the front wall (106d).

6. The propulsion assembly (100) according to claim 4 or 5, characterized in that: Each support ring (241) includes a cutout (241a) that allows the fire extinguisher bottle (21) to be installed and removed from the support ring (241).

7. The propulsion assembly (100) according to any one of claims 4 to 6, characterized in that: Each support ring (241) comprises a locking device (25) for removably fixing one of the at least one fire extinguisher bottle (21) on the support ring (241), and the locking device (25) is arranged to allow locking and unlocking of the fire extinguisher bottle (21) on the support ring (241).

8. Aircraft (100) having a propulsion assembly (100) according to any one of the preceding claims.

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