CN114790943A

CN114790943A - Air inlet duct of aircraft engine nacelle and aircraft engine nacelle

Info

Publication number: CN114790943A
Application number: CN202110097189.0A
Authority: CN
Inventors: 打玉宝; 周颂平; 孙利兵
Original assignee: AECC Commercial Aircraft Engine Co Ltd
Current assignee: AECC Commercial Aircraft Engine Co Ltd
Priority date: 2021-01-25
Filing date: 2021-01-25
Publication date: 2022-07-26

Abstract

The invention discloses an air inlet channel of an aircraft engine nacelle and the aircraft engine nacelle. The air inlet channel of the aircraft engine nacelle comprises an inner wall plate and a butt joint ring, wherein a gas flow channel surface is formed on the inner surface of the inner wall plate, a first matching surface is formed on the outer surface of the inner wall plate, the butt joint ring is used for connecting the inner wall plate and the fan case, the butt joint ring comprises a second matching surface, the second matching surface and the first matching surface are mutually attached and connected, and the first matching surface and the second matching surface are single curved surfaces. The matching surface of the butt joint ring of the air inlet channel and the inner wall plate adopts a single curved surface, so that the mechanical processing and manufacturing of the butt joint ring are facilitated. When the butt-joint ring is horizontally assembled and installed with the inner wall plate along the axis of the engine, the butt-joint ring can be installed to a theoretical position from the rear end of the inner wall plate, and the assembling and installing path is shortened to the maximum extent.

Description

Air inlet duct of aircraft engine nacelle and aircraft engine nacelle

Technical Field

The invention relates to an air inlet channel of an aircraft engine nacelle and the aircraft engine nacelle.

Background

The civil turbofan engine nacelle system generally comprises an air inlet and exhaust system, a fan cover and a thrust reverser, and specifically comprises an air inlet, a fan casing, a thrust reverser, a nozzle and a center cone. Functionally, the air inlet channel mainly rectifies external air flow, and simultaneously, the external air flow is rectified and guided into the engine fan blades according to a set flow channel through the lip and the inner wall plate structure of the air inlet channel, which are positioned on the flow channel surface. Structurally, the air inlet channel is connected with the fan casing through the butt joint ring in an installing mode, and meanwhile, the butt joint ring is connected with the inner wall plate structure on the flow channel face.

Disclosure of Invention

The invention provides an air inlet channel of an aircraft engine nacelle and the aircraft engine nacelle so as to reduce the processing difficulty of a butt joint ring.

In a first aspect the present invention provides an air scoop for a nacelle of an aircraft engine, comprising:

an inner wall plate, an inner surface of which forms a gas flow passage surface and an outer surface of which includes a first mating surface; and

the butt joint ring is used for connecting the inner wallboard and the fan casing and comprises a second matching surface, the second matching surface is mutually attached and connected with the first matching surface, and the first matching surface and the second matching surface are single curved surfaces.

In some embodiments, the single curved surface is centered on the centerline of the aircraft engine.

In some embodiments, the single curved surface comprises a cylindrical or conical surface.

In some embodiments, the inner wall panel comprises a face plate, a back plate and a honeycomb, the honeycomb is sandwiched between the face plate and the back plate, the back plate forms an outer surface of the inner wall panel, the back plate comprises a back plate main body section and a back plate connecting section, the back plate connecting section is located at the axial rear end of the back plate main body section and forms a first mating surface, the honeycomb comprises a honeycomb main body section corresponding to the back plate main body section and a honeycomb connecting section corresponding to the back plate connecting section, and the nacelle air inlet further comprises a connecting piece which connects the docking ring and the inner wall panel.

In some embodiments, the connector passes through the docking ring, the backplane connection segment, the honeycomb connection segment, and the face plate in sequence.

In some embodiments, the honeycomb density of the honeycomb connecting section is greater than the honeycomb density of the honeycomb main body section.

In some embodiments, the honeycomb density of the honeycomb connecting section is the same as that of the honeycomb main body section, and the nacelle inlet further comprises a counter-sunk bush penetrating into the inner wall plate from the panel side and wrapping outside the connecting piece.

In some embodiments, the second mating surface is clearance fit with the first mating surface.

In a second aspect, the invention provides an aircraft engine nacelle comprising an air intake duct as described above.

The air inlet channel of the aircraft engine nacelle comprises an inner wall plate and a butt joint ring, wherein a gas flow channel surface is formed on the inner surface of the inner wall plate, the outer surface of the inner wall plate comprises a first matching surface, the butt joint ring is used for connecting the inner wall plate and a fan case, the butt joint ring comprises a second matching surface, the second matching surface and the first matching surface are mutually attached and connected, and the first matching surface and the second matching surface are both single curved surfaces. The matching surface of the butt joint ring of the air inlet channel and the inner wall plate adopts a single curved surface, so that the butt joint ring is convenient to machine and manufacture. When the butt-joint ring is horizontally assembled and installed with the inner wall plate along the axis of the engine, the butt-joint ring can be installed to the theoretical position from the rear end of the inner wall plate, and the assembling and installing path is shortened to the maximum extent.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments of the invention, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention and do not constitute a limitation of the invention. In the drawings:

FIG. 1 is a schematic structural view of an aircraft engine nacelle;

FIG. 2 is a schematic cross-sectional view of an intake duct;

FIG. 3 is a perspective view of the inner wall plate and docking ring of FIG. 2;

FIG. 4 is a block diagram of the inner wall panel and docking ring of FIG. 2;

FIG. 5 is an enlarged view of a portion of the inner wall panel and docking ring of FIG. 4;

FIG. 6 is an installation view of the docking ring and inner wall plate of FIG. 2;

FIG. 7 is a schematic view of the structure of the docking ring and the inner wall plate according to the embodiment of the present invention;

FIG. 8 is an enlarged view of a portion of the docking ring attached to the inner wall plate of FIG. 7;

FIG. 9 is a block diagram of an embodiment of an inlet and a fan casing;

FIG. 10 is a schematic view of an installation section and a step adjustment compensation design method of an air inlet and a fan casing according to an embodiment of the present invention;

FIG. 11 is a schematic view of the connection of the docking ring to the inner wall plate according to an embodiment of the present invention;

FIG. 12 is a schematic view of an inlet docking ring and an inner wall plate according to another embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as exemplary only and not as limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Spatially relative terms, such as "above … …," "above … …," "above … … surface," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously positioned and the spatially relative descriptors used herein interpreted accordingly.

As shown in fig. 1, the nacelle of an aircraft engine according to some embodiments of the present invention includes an air intake duct 1, a fan case 2, a thrust reverser 3, a nozzle, and a center cone 4.

As shown in fig. 2, in some embodiments, the intake duct 1 includes a front bulkhead 11, a rear bulkhead 12, an outer wall plate 13, an inner wall plate 14, a docking ring 15, and a lip 16. Wherein, the lip 16 is connected in the front side of preceding bulkhead 11, and the front and back both ends of outer wall board 13 are connected with preceding bulkhead 11 and back bulkhead 12 respectively, and the front and back both ends of inner wall board 14 are connected with preceding bulkhead 11 and back bulkhead 12 respectively, and wherein inner wall board 14 sets up in radial inboard, and outer wall board 13 sets up in radial outside. The docking ring 15 is used to connect the inner wall plate 14 and the fan case 2.

As shown in fig. 3, in some embodiments, the inner wall panel 14 is annular in shape, and the inner surface of the inner wall panel 14 forms a gas flow path surface. As shown in fig. 4, the outer surface of the inner wall plate 14 is connected to the docking ring 15.

The inner wall panel 14 has an acoustic liner noise reduction function to suppress noise of the fan blade. To maximize the effective acoustic liner noise reduction area of the inner wall panel 14, an integral seamless acoustic liner structure is generally used, i.e., the inner wall panel 14 is a circumferential integral seamless closed structure. Accordingly, the docking ring 15 is connected to the fan case 2 at one end and to the inner wall plate 14 at the other end. The fan casing 2 is also called a fan containing casing, fragments are not allowed to fly out of the casing to damage peripheral accessories under the working condition of FBO blade shedding load, so that an axial maintaining structure is designed to be continuous without a weak area, and a ring-shaped integral seamless casing structure mode is usually adopted. Correspondingly, the docking ring 15 is directly connected to the fan casing 2, and has a 360 ° overall ring structure for FBO load operation. Similarly, the inner wall panel 14 is also of unitary seamless construction. And the fitting connection areas of the two large-size integrated annular structures are shown in fig. 4 and 5, and the fitting surfaces of the abutting ring 15 and the inner wall plate 14 are parallel to the flow passage surface. Therefore, as the flow passage surface is a hyperbolic surface, the butt-joint ring 15 also needs to adopt the hyperbolic surface, which increases the manufacturing and processing cost of the butt-joint ring, increases the process difficulty, and reduces the processing efficiency. Secondly, due to the characteristic of the double curved surface that defines the flow passage surface, the profile at the butt joint ring is usually flared at the position, that is, the front end of the flow passage surface at the joint of the butt joint ring 15 and the inner wall plate 14 is small and the rear end is large, which determines the assembly relationship between the two, as shown in fig. 6, that is, the butt joint ring 15 can only penetrate through the whole inner wall plate from the front edge until reaching the installation position, the assembly operation is difficult, the assembly stroke is long, and during the process of nesting two large-sized parts in the installation process, the fault of scratching or even impact damage is easily caused.

As shown in fig. 5, in some embodiments, the inner wall panel 14 includes a face panel 14a, a back panel 14b, and a honeycomb 14 c. In one embodiment, the face sheet 14a and the back sheet 14b are typically carbon fiber composite. The panel 14a has noise-reducing perforation geometrical characteristics, the sandwich layer honeycomb 14c is a Nomex aramid paper honeycomb, and the three are subjected to molding bonding in a curing mode of co-bonding or secondary bonding. In another embodiment, the face sheet 14a and the back sheet 14b are made of aluminum alloy and are bonded to the honeycomb 14 c. The above-mentioned inner wall plate structure and materials are only two examples, and the practical implementation includes but not limited to the above-mentioned materials and processes, and may also be a combination of the above two materials.

In the embodiment that the face plate 14a and the back plate 14b are made of carbon fiber composite materials, where the inner wall plate 14 and the butt ring 15 are assembled, the carbon fiber layer of the back plate 14b is locally thickened, and a glass cloth sacrificial layer is added on one side close to the butt ring 15, and the glass cloth sacrificial layer can be polished and repaired, so that the inner wall plate and the butt ring can be assembled conveniently. When the air inlet duct 1 and the fan casing 5 are matched and assembled with the butt-joint ring 15, the butt-joint ring is partially or wholly repaired to achieve the purpose of adjusting the assembling step difference of the whole air inlet duct 1 and the fan casing 5. Similarly, in the embodiment that the front panel 14a and the back panel 14b are made of aluminum alloy thin-film structures, where the inner wall panel 14 and the docking ring 15 are assembled, the back panel 14b is made of chemical milling or machining to realize the thickening of the structure and reserve machining or grinding process margins that may be needed in the subsequent assembly.

The butt-joint ring 15 is an aluminum alloy structure added by an integral ring forging machine, and is generally wrapped by a fireproof blanket in design from the viewpoint of fireproof requirements. When the area of the butt joint ring is a non-fire area, a fire blanket is not needed.

In view of the problem of high manufacturing and processing difficulty of the docking ring, the embodiment of the invention provides an aircraft engine nacelle in order to reduce the manufacturing difficulty of the docking ring.

Referring to fig. 7 and 8, the air intake duct of the nacelle of the aircraft engine of some embodiments includes an inner wall plate 17 and a docking ring 18. Wherein the inner surface of the inner wall panel 17 forms a gas flow passage surface and the outer surface of the inner wall panel 17 comprises a first mating surface. The docking ring 18 is used to connect the inner wall plate 17 and the fan case 2, and the docking ring 18 includes a second mating surface. The second matching surface is mutually attached and connected with the first matching surface, and the first matching surface and the second matching surface are both single curved surfaces.

The matching surface of the butt-joint ring 18 and the inner wall plate 17 of the air inlet of some embodiments adopts a single curved surface, so that the machining and manufacturing of the butt-joint ring are facilitated. When the inner wall plate 17 is horizontally assembled and mounted along the axis of the engine, the docking ring 18 can be mounted from the rear end of the inner wall plate 17 to the theoretical position, and the assembly and mounting path can be shortened to the maximum extent. In the embodiment shown in fig. 6, the docking ring is installed from the front end of the inner wall plate, the installation path is long, and the docking ring needs to finely adjust the installation angle for many times so as to avoid interference damage with the back plate of the inner wall plate during the installation process.

In some embodiments, the single curved surface is centered on the centerline of the aircraft engine. Therefore, the first matching surface and the second matching surface are coaxially arranged, and the assembly is convenient.

In some embodiments, the single curved surface comprises a cylindrical surface. Adopt the butt joint ring structure of cylinder revolution mechanic, manufacturing cost reduces, the processing technology degree of difficulty reduces and processing cycle shortens. In other embodiments, the single curved surface may also be a conical surface.

As shown in fig. 8, the outer surface of the inner wall plate 17 of the present embodiment includes a first mating surface and a main wall surface provided on the axially front side of the first mating surface, the main wall surface being parallel to the flow path surface. That is, the inner wall plate 17 of the present embodiment is divided into two sections in the axial direction, the front main wall surface is parallel to the flow path surface, the first mating surface at the rear end is a single curved surface, and the main wall surface and the first mating surface are not smoothly connected.

In some embodiments, referring to fig. 10, the second mating surface is clearance fit with the first mating surface. That is to say, a certain assembly gap D is designed and reserved between the assembly matching surfaces of the docking ring 18 and the inner wall plate 17 to compensate for processing and manufacturing deviations and assembly errors of two large-size annular structures, and referring to fig. 9 and fig. 10, the assembly gap D is also used to adjust the axial positions of the docking ring 18 and the fan case 2 of the whole air inlet duct 1, so as to control the step difference of the flow channel surface after the air inlet duct 1 and the fan case 2 are installed, and to meet the design requirement of aerodynamic smoothness of the flow channel surface.

In some embodiments, when the inner wall plate 17 at the flow passage surface is assembled with the docking ring 18, if the docking ring 18 interferes with the inner wall plate 17, the cylindrical mating surface facilitates the repair and even the additional machining of the docking ring to complete the assembly. When a certain gap exists between the matching surfaces, the solid gasket which is equal in thickness and is also cylindrical can be adopted to compensate the assembly gap, and the solid gasket is matched with the liquid gasket for use until the airflow step difference of the flow channel surface formed by the assembled solid gasket and the fan casing 2 completely meets the pneumatic requirement.

In some embodiments, referring to fig. 8, the inner wall panel 17 includes a face panel 17a, a back panel 17b, and a honeycomb 17c, the honeycomb 17c is sandwiched between the face panel 17a and the back panel 17b, the back panel 17b forms an outer surface of the inner wall panel 17, the back panel 17b includes a back panel main body section and a back panel connection section, the back panel connection section is located at an axial rear end of the back panel main body section and forms a first mating surface, the honeycomb 17c includes a honeycomb main body section corresponding to the back panel main body section and a honeycomb connection section corresponding to the back panel connection section, the nacelle inlet further includes a connecting member 6, and the connecting member 6 connects the docking ring 18 and the inner wall panel 17.

In particular, the connecting piece 6 is a high lock bolt. In some embodiments, the connecting member 6 extends through the entire inner wall plate 17 to the pneumatic flow path surface, and specifically, the connecting member 6 passes through the docking ring 18, the back plate connecting section, the honeycomb connecting section, and the face plate 17a in this order.

To strengthen the honeycomb connecting section, in some embodiments, referring to fig. 11, the honeycomb density of the honeycomb connecting section 17d is greater than the honeycomb density of the honeycomb main body section 17 e. Specifically, the honeycomb connecting section 17d employs a high-density aluminum honeycomb. In other embodiments, referring to fig. 12, the honeycomb density of the honeycomb connecting section is the same as that of the honeycomb main body section, and the nacelle air inlet further includes a counter sink 7, and the counter sink 7 penetrates into the inner wall panel 17 from the side of the panel 17a and wraps outside the connecting member 6. In this embodiment, the honeycomb connecting section and the honeycomb main body section are made of common honeycomb materials, that is, the honeycomb of the whole inner wall plate is made of the same material, and the countersunk bushings 7 are embedded in the inner wall plate only at the installation holes of the high-lock bolts connected with the butt-joint rings 18 for through mechanical connection of the high-lock bolts.

In some embodiments not shown in the drawings, blind rivets may also be used to connect the abutment ring 18 to the inner panel 17 in a manner that does not extend through the entire inner panel. Of course, a hybrid connection may also be made by using a combination of high-lock bolts and blind rivets penetrating the abutment ring 18 and the inner wall plate 17.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that: modifications of the embodiments of the invention or equivalent substitutions for parts of the technical features are possible; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.

Claims

1. An air scoop for an aircraft engine nacelle, comprising:

an inner wall plate having an inner surface forming a gas flow passage surface and an outer surface including a first mating surface; and

2. The air scoop according to claim 1, wherein the single curved surface is centered on the centerline of the aircraft engine.

3. The air scoop according to claim 1, wherein the single curved surface comprises a cylindrical surface or a conical surface.

4. The air inlet duct of an aircraft engine nacelle according to claim 1, wherein the inner panel includes a face plate, a back plate, and a honeycomb, the honeycomb clamp is disposed between the face plate and the back plate, the back plate forms an outer surface of the inner panel, the back plate includes a back plate main body section and a back plate connecting section, the back plate connecting section is located at an axial rear end of the back plate main body section and forms the first mating surface, the honeycomb includes a honeycomb main body section corresponding to the back plate main body section and a honeycomb connecting section corresponding to the back plate connecting section, the nacelle air inlet duct further includes a connecting member, and the connecting member connects the docking ring and the inner panel.

5. The air inlet duct of an aircraft engine nacelle according to claim 4, wherein the connection piece passes through the docking ring, the back plate connection section, the honeycomb connection section, and the face plate in this order.

6. The air scoop according to claim 5, wherein the honeycomb density of the honeycomb connecting section is greater than the honeycomb density of the honeycomb main body section.

7. The air inlet duct for an aircraft engine nacelle according to claim 5, wherein the honeycomb density of the honeycomb connecting section is the same as that of the honeycomb main body section, and the nacelle air inlet duct further comprises a counter-sunk bush which penetrates into the inner wall plate from the panel side and wraps outside the connecting member.

8. The air scoop of an aircraft engine nacelle according to claim 1, wherein said second mating surface is a clearance fit with said first mating surface.

9. An aircraft engine nacelle, characterised in that it comprises an air inlet duct according to any one of claims 1 to 8.