Stiffened panel with stiffener stringers and method of manufacturing thereof

Abstract

The application relates to the field of aviation manufacturing technology, in particular to a stiffened wall panel with a long stringer with a reinforcing layer and a preparation method thereof. The stiffened wall panel with the long stringer with the reinforcing layer comprises a long stringer, a skin, a reinforcing layer and a twist strip, the long stringer comprises a web and a flange, the web is provided with the flange at both ends in the width direction; the web is provided with a round corner transition part between the corresponding flange at both ends in the width direction. In the direction of the skin profile, a plurality of long strings are arranged side by side to form a combination, and the skin is attached to the outer surface of the plurality of webs of the combination. The reinforcing layer is arranged between the two flanges close to each other, the first end of the reinforcing layer is arranged at intervals with the skin, the first end is attached to any one of the two adjacent round corner transition parts, and the two round corner transition parts close to each other in the two adjacent long strings form a triangular region. The twist strip is filled in the triangular region. The long stringer with the reinforcing layer reduces the processing cost and installation cost of the twist strip and improves the forming quality.

Description

Technical Field

[0001] This invention relates to the field of aerospace manufacturing technology, and in particular to a stiffened wall panel with a reinforcing layer stringer and its preparation method. Background Technology

[0002] In aircraft manufacturing, composite stiffened panels are widely used in components such as wings, tail fins (horizontal and vertical stabilizers), and control surfaces (elevators, rudders). The stringer components in these stiffened panels typically have different structural forms, such as I-beams, T-beams, or U-beams. For example... Figure 1 In the reinforced wall panel formed using the co-curing process, the middle part is a U-shaped stringer, and the outermost part is an L-shaped stringer (or a U-shaped stringer). After the U-shaped stringer and the L-shaped stringer (or U-shaped stringer) are combined, the rounded transition positions of adjacent stringers form a triangular-like area. The reinforcing layer is usually inserted into the triangular-like area and directly contacts the skin, thus dividing the triangular-like area in two. Since the initial layer of the skin in contact with the stringer is curved, two twist strips with different configurations need to be filled in the same triangular-like area. That is, the number of twist strips doubles with the increase of the number of stringers, and the shape of each twist strip is different, which increases the cost of the die tooling for manufacturing the twist strips, resulting in high manufacturing and installation costs. Moreover, the initial layer of the skin contacts two twist strips and one reinforcing layer in the same triangular-like area, making it easy for the skin fibers to wrinkle during the forming process of the reinforced wall panel, reducing the forming quality of the reinforced wall panel. Summary of the Invention

[0003] The purpose of this invention is to provide a stiffened wall panel with a reinforcing layer stringer and its preparation method, so as to reduce the number of twist strips, reduce the processing cost and installation cost of twist strips, reduce the risk of wrinkles in the skin fiber during the forming process of the stiffened wall panel, and improve the forming quality of the stiffened wall panel with a reinforcing layer stringer.

[0004] To achieve this objective, the technical solution adopted by the present invention is as follows:

[0005] Stiffened wall panels with reinforced girder layers include:

[0006] A stringer includes a web and flanges. The flanges are provided at both ends of the web along the width direction to make the stringer U-shaped. Rounded transition portions are provided between the two ends of the web and the corresponding flanges along the width direction.

[0007] A skin, along the profile direction of the skin, multiple stringers are arranged side by side to form an assembly, and the skin is attached to the outer surface of multiple webs of the assembly;

[0008] The reinforcing layer is sandwiched between two adjacent flanges in two adjacent stringers. The first end of the reinforcing layer facing the web is spaced apart from the skin. The first end is attached to any one of the two adjacent rounded transition portions, so that a triangular-like region is formed between the two adjacent rounded transition portions in the two stringers of the assembly.

[0009] The twist strip is filled in each of the triangular-like regions. The stringer, the skin, the reinforcing layer and the twist strip are connected together by a co-curing process.

[0010] As an alternative, the second end of the reinforcing layer away from the web is flush with the top end of the flange; the thickness of the first end gradually decreases along the direction from the second end toward the first end.

[0011] As an optional solution, the assembly also includes an L-shaped stringer, which includes a first plate and a second plate connected at an angle, and the first plate and the second plate are connected by a rounded corner transition.

[0012] Along the profile direction of the skin, the two L-shaped stringers are located on the outermost side of the assembly. The outer surface of each first plate is attached to the skin, and the reinforcing layer is sandwiched between each second plate and the adjacent flange. The rounded transition area of ​​the L-shaped stringer and the adjacent rounded transition portion form a triangular-like area.

[0013] A method for preparing a stiffened wall panel with a reinforcing truss with a reinforcing layer, used to prepare the aforementioned stiffened wall panel with a reinforcing truss with a reinforcing layer, the method comprising the following steps:

[0014] S1: The stringer, the reinforcing layer, and the twist strip are prepared using prepregs;

[0015] S2: Part of the stringer is installed at the hard mold position of the wall panel forming fixture, and multiple reinforcing layers are respectively attached to the outer side of the flange of the stringer at the hard mold position, and the first end of the reinforcing layer is attached to the outer side of the corresponding rounded corner transition portion.

[0016] S3: Another part of the stringers are installed at the soft mold position of the wall panel forming tooling, and the hard mold position and the soft mold position are alternately arranged along the profile direction of the skin, so that multiple stringers are arranged side by side to form the assembly;

[0017] S4: The plurality of twisted strips are respectively filled into the corresponding triangular-shaped regions;

[0018] S5: The skin is laid on the outer surface of the web of the assembly to form a preform;

[0019] S6: Sequentially lay an isolation mold, a breathable felt, and a vacuum bag on the outer surface of the preform, and then paste the vacuum bag together;

[0020] S7: The preform enters the autoclave for curing and molding;

[0021] S8: Remove the bag and demold the cured preform.

[0022] As an optional solution, in step S1, the stringer installed at the hard mold position is prepared by a hard mold tooling, the stringer installed at the soft mold position is prepared by a soft mold tooling, and the twist strip is extruded and formed by a die tooling after the prepreg is fed and rolled.

[0023] As an optional solution, in step S2, the stringer prepared by the soft mold tooling is installed together with the corresponding soft mold tooling at the soft mold position.

[0024] As an optional solution, step S4 further includes: after the twist strip is installed, pre-compacting the assembly and the twist strip.

[0025] As an alternative, the cover plate is pressed against the outer surfaces of the multiple web plates and the multiple twist strips of the assembly, and then the vacuum bag is put on for vacuum pre-compaction.

[0026] As an alternative, in step S8, after unpacking, positioning holes are machined on the stiffened wall panel of the reinforcing truss with the reinforcing layer, and then demolding is performed.

[0027] As an optional solution, step S8 is followed by step S9: the stiffened wall panel with the reinforcing layer stringer is transferred to a milling fixture for finishing.

[0028] The beneficial effects of this invention are as follows:

[0029] The present invention proposes a stiffened wall panel with reinforcing stringers. Multiple stringers are arranged side-by-side along the profile of the skin to form an assembly. Within the assembly, a triangular-like region is formed between the two rounded corner transitions of adjacent stringers. Each triangular-like region is filled with a twisted strip. The stringers, skin, reinforcing layer, and twisted strip are connected as a single unit through a co-curing process. Because the first end of the reinforcing layer facing the web is spaced apart from the skin, and the first end is attached to any one of the two adjacent rounded corner transitions, the triangular-like regions are treated as a single unit. This avoids the reinforcing layer separating the triangular-like regions, meaning only one twisted strip is needed to fill each region, reducing the number of twisted strips and lowering processing and installation costs. Furthermore, within the triangular-like regions, the reinforcing layer does not contact the skin; only the twisted strip contacts the skin. This reduces the risk of wrinkles in the skin fibers during the stiffened wall panel forming process, improving the forming quality of the stiffened wall panel with reinforcing stringers.

[0030] The method for preparing a stiffened wall panel with a reinforcing layer stringer proposed in this invention reduces the number of twist strips, lowers the processing and installation costs of the twist strips, and reduces the risk of wrinkles in the skin fiber during the forming process of the stiffened wall panel, thereby improving the forming quality of the stiffened wall panel with a reinforcing layer stringer. Attached Figure Description

[0031] Figure 1 This is a structural schematic diagram of a reinforced wall panel with a reinforcing layer, comprising two L-shaped long trusses and one long truss (U-shaped), provided in Embodiment 1 of the present invention.

[0032] Figure 2 This is a schematic diagram of the structure of the stiffened wall panel with a reinforcing layer and a long stringer, including a soft mold tooling, provided in Embodiment 1 of the present invention, in the wall panel forming tooling.

[0033] Figure 3 This is a detailed flowchart of the preparation method of the stiffened wall panel with a reinforcing layer truss provided in Embodiment 2 of the present invention.

[0034] The component names and labels in the diagram are as follows:

[0035] 10. Panel forming fixture; 20. Flexible mold fixture;

[0036] 1. Long stringer; 11. Web plate; 12. Flanged strip; 13. Rounded corner transition section; 2. Skin; 3. Reinforcing layer; 31. First end; 4. Twisted strip; 5. Triangular area; 6. L-shaped long stringer; 61. First plate; 62. Second plate. Detailed Implementation

[0037] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0038] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0040] In the description of this embodiment, the terms "upper," "lower," "right," and "left," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0041] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0042] Example 1

[0043] like Figure 1 and Figure 2As shown, this embodiment proposes a reinforced wall panel with a reinforcing girder. The reinforced wall panel with a reinforcing girder includes a girder 1, a skin 2, a reinforcing layer 3, and a twist strip 4. The girder 1 includes a web 11 and a flange 12. The web 11 has flanges 12 at both ends along its width direction, making the girder 1 U-shaped. Rounded transition portions 13 are provided between the web 11 and the corresponding flanges 12 at both ends along its width direction. Multiple girder 1s are arranged side by side along the profile direction of the skin 2 to form an assembly. The skin 2 is attached to the outer surface of the multiple webs 11 of the assembly. In two adjacent girder 1s, a reinforcing layer 3 is sandwiched between two adjacent flanges 12. The first end 31 of the reinforcing layer 3 facing the web 11 is spaced apart from the skin 2. The first end 31 is attached to any one of the two adjacent rounded transition portions 13, so that the two adjacent rounded transition portions 13 of two adjacent girder 1s in the assembly form a triangular region 5. Each triangular region 5 is filled with a twist strip 4. The stringer 1, skin 2, reinforcing layer 3 and twist strip 4 are connected together by a co-curing process.

[0044] Multiple stringers 1 are arranged side-by-side along the profile of the skin 2 to form an assembly. Within the assembly, two adjacent rounded corner transition sections 13 of two adjacent stringers 1 form a triangular region 5. Each triangular region 5 is filled with a twill strip 4. The stringers 1, skin 2, reinforcing layer 3, and twill strip 4 are connected as a single unit through a co-curing process. Because the first end 31 of the reinforcing layer 3 facing the web 11 is spaced apart from the skin 2, and the first end 31 is attached to any one of the two adjacent rounded corner transition sections 13, the triangular regions 5 are integrated as a whole. This avoids the reinforcing layer 3 separating the triangular regions 5, meaning that each triangular region 5 only requires one twill strip 4 for filling, reducing the number of twill strips 4 and lowering their processing and installation costs. Moreover, within the triangular region 5, the reinforcing layer 3 does not come into contact with the skin 2, and only the twist strip 4 comes into contact with the skin 2. This reduces the risk of wrinkles appearing in the fibers of the skin 2 during the forming process of the stiffened wall panel (i.e., the stiffened wall panel with the reinforcing layer stringer), and improves the forming quality of the stiffened wall panel with the reinforcing layer stringer.

[0045] The aforementioned reinforcing layer 3, twist strip 4, and skin 2 are all carbon fiber composite materials. Skin 2 can be the outer skin of structural components such as wings or tail fins, so that the profile of skin 2 corresponds to the profile of the corresponding wing or tail fin structural component; that is, the profile of skin 2 is curved. The aforementioned stringers 1 have various configurations, and the web 11 of stringers 1 is as follows... Figure 2As shown, the webs 11 are arranged side by side, with each web plate 11 being arc-shaped so that each web plate 11 fits snugly against the skin 2. One flange 12 of the stringer 1 along the width direction is close to the flange 12 of the adjacent stringer 1 on the left, and a reinforcing layer 3 is provided between the two flanges 12; another flange 12 of the stringer 1 along the width direction is close to the flange 12 of the adjacent stringer 1 on the right, and a reinforcing layer 3 is provided between the two flanges 12.

[0046] It should be noted that the various structural stringers 1 described above are prepared using corresponding molds and fixtures (hard mold fixtures and soft mold fixtures 20) to ensure the dimensional accuracy of the stringers 1. After preparation, the stringers 1 are installed in the wall panel forming fixture 10, which is assembled according to the dimensions of the stiffened wall panel with the reinforcing stringers. The wall panel forming fixture 10 has a hard mold position, a soft mold position, and a position for placing the skin 2, and the hard mold position and the soft mold position are alternately arranged along the profile direction of the skin 2. Part of the stringer 1 is prepared using a hard mold tooling, while another part of the stringer 1 is prepared using a soft mold tooling 20. The stringer 1 prepared using the hard mold tooling needs to be demolded and then installed in the hard mold position of the wall panel forming tooling 10. The stringer 1 prepared using the soft mold tooling 20 is installed together with the corresponding soft mold tooling 20 in the soft mold position of the wall panel forming tooling 10, so as to support the corresponding stringer 1 through the soft mold tooling 20, thereby ensuring that the two adjacent flanges 12 in the assembly clamp the middle reinforcing layer 3, so as to achieve the pre-tightening installation of the assembly.

[0047] First, install the stringer 1 at the hard mold position. Then, attach and install the reinforcing layer 3 on the outside of the flange 12 of the stringer 1 at the hard mold position (towards the adjacent stringer 1). Next, install the stringer 1 at the soft mold position (with soft mold tooling 20). Then, fill the corresponding twist strips 4 into each triangular area 5, and then lay the skin 2, so that the skin 2 combines with multiple webs 11 and multiple twist strips 4 to form a preform. Finally, the preform is placed in a vacuum bag and cured in an autoclave, and then demolded. The above-mentioned mold tooling is a commonly used tooling mold in the field of aircraft manufacturing for preparing stringers 1 (or panels). It can be customized and assembled according to different stringer 1 (or panel) structures, and will not be described in detail here.

[0048] like Figure 1 and Figure 2As shown, the second end of the reinforcing layer 3, away from the web 11, is flush with the top of the flange 12. Along the direction from the second end towards the first end 31, the thickness of the first end 31 gradually decreases. This arrangement makes the first end 31 of the reinforcing layer 3 have a gradient structure, and the closer it is to the web 11, the thinner the first end 31 becomes. This facilitates the fitting and installation of the reinforcing layer 3, making the triangular-like region 5 a single, integrated area. It avoids the reinforcing layer 3 separating the triangular-like region 5, thus requiring only a single, integral twist strip 4 to fill the corresponding triangular-like region 5. It should be noted that the aforementioned triangular-like region 5 is formed by the arcuate surface of the rounded transition portion 13 (where the edge is not attached to the reinforcing layer 3), the arcuate surface of the first end 31 of the reinforcing layer 3, and the skin 2.

[0049] like Figure 1 and Figure 2 As shown, the assembly also includes an L-shaped stringer 6, which comprises a first plate 61 and a second plate 62 connected at an angle, with the first plate 61 and the second plate 62 connected by a rounded transition. Along the profile direction of the skin 2, the two L-shaped stringers 6 are located on the outermost side of the assembly. The outer surface of each first plate 61 is fitted and connected to the skin 2, and each second plate 62 has a reinforcing layer 3 sandwiched between it and the adjacent flange 12. The rounded transition area of ​​the L-shaped stringer 6 and the adjacent rounded transition portion 13 form a triangular-like region 5. U-shaped stringers 1 or L-shaped stringers 6 can be selectively installed at the two side edges of the assembly, which can be flexibly adjusted according to the structural requirements of the stiffened wall panel with the reinforcing layer stringers, and no specific limitation is made here.

[0050] Example 2

[0051] like Figure 3 As shown, this embodiment proposes a method for preparing a stiffened wall panel with a reinforcing layer girder. This method is used to prepare the stiffened wall panel with a reinforcing layer girder as described in Embodiment 1. The method includes the following steps:

[0052] S1: The stringer 1, the reinforcing layer 3, and the twist strip 4 are prepared by prepreg.

[0053] S2: Part of the stringer 1 is installed at the hard mold position of the wall panel forming fixture 10, and multiple reinforcing layers 3 are respectively attached to the outer side of the flange 12 of the stringer 1 at the hard mold position, and the first end 31 of the reinforcing layer 3 is attached to the outer side of the corresponding rounded corner transition part 13.

[0054] S3: Another part of the stringers 1 is installed at the soft mold position of the panel forming fixture 10, and the hard mold position and the soft mold position are alternately set along the profile direction of the skin 2 so that multiple stringers 1 are arranged side by side to form a combination.

[0055] S4: Multiple twisted strips 4 are respectively filled into the corresponding triangular-shaped regions 5.

[0056] S5: Skin 2 is laid on the outer surface of the web 11 of the assembly to form a preform.

[0057] S6: Lay out the isolation mold, breathable felt and vacuum bag in sequence on the outer surface of the preform, and then paste the vacuum bag.

[0058] S7: The preform enters the autoclave for curing and molding.

[0059] S8: Remove the bag and demold the cured preform.

[0060] Because the first end 31 of the reinforcing layer 3 facing the web 11 is spaced apart from the skin 2, and the first end 31 is attached to any one of the two adjacent rounded corner transition portions 13, the triangular region 5 is a whole, avoiding the reinforcing layer 3 from separating the triangular region 5. This means that each triangular region 5 only needs one twist strip 4 for filling, reducing the number of twist strips 4 and lowering the processing and installation costs of the twist strips 4. Moreover, within the triangular region 5, the reinforcing layer 3 does not contact the skin 2, only the twist strip 4 contacts the skin 2, reducing the risk of wrinkles in the skin 2 fibers during the forming process of the stiffened wall panel, and improving the forming quality of the stiffened wall panel with the reinforcing layer stringer.

[0061] The method for preparing a stiffened wall panel with a reinforcing layer and a long stringer proposed in this invention ensures that the reinforcing layer 3 does not contact the skin 2 and does not separate the triangular-shaped regions 5. Each triangular-shaped region 5 only needs to be filled by one twist strip 4, which reduces the number of twist strips 4, lowers the processing and installation costs of twist strips 4, reduces the risk of wrinkles in the fibers of the skin 2 during the forming process of the stiffened wall panel, and improves the forming quality of the stiffened wall panel with a reinforcing layer and a long stringer.

[0062] by Figure 2 The preparation method of a reinforced wall panel with reinforced stringers is explained using five stringers 1, four reinforcing layers 3 and four twist strips 4 as an example.

[0063] In step S1, stringers 1 installed in the hard mold position are prepared using a hard mold tooling, and stringers 1 installed in the soft mold position are prepared using a soft mold tooling 20. Twisted strips 4 are extruded and formed by a die tooling after the prepreg is fed and rolled. Specifically, the prepreg is automatically laid and cut in three hard mold toolings and two soft mold toolings 20 to achieve the pre-forming of five stringers 1. The aforementioned hard mold tooling and soft mold tooling 20 respectively prepare stringers 1 with different structures.

[0064] In step S2, the stringers 1 prepared by the soft mold tooling 20 are installed together with the corresponding soft mold tooling 20 at the soft mold position. Specifically, after demolding the three stringers 1 prepared by the hard mold tooling, they are respectively installed in the three hard mold holes spaced apart in the wall panel forming tooling 10. Among the two stringers 1 located at the edge, a reinforcing layer 3 is attached to the outer side of one of the flanges 12 (the stringer 1 near the middle position), and a reinforcing layer 3 is attached to the outer side of both flanges 12 of the stringer 1 in the middle position. The first end 31 of each reinforcing layer 3 is attached to the rounded transition portion 13 at the corresponding flange 12. Then, the stringers 1 with the soft mold tooling 20 are installed at the corresponding soft mold position so that the five stringers 1 are arranged side by side. Under the support of the soft mold tooling 20, two adjacent flanges 12 clamp the same reinforcing layer 3, realizing the pre-tightening installation of the assembly.

[0065] Before step S4, the filling amount of each triangular region 5 is obtained by measuring the area of ​​the triangular region 5 (which can be measured in the model drawing of the stiffened panel with the reinforcing stringer). After the prepreg is rolled out, it is extruded in a customized die fixture, and then pultruded in a preforming equipment. The aforementioned die fixture and preforming equipment are commonly used in the aircraft manufacturing industry, and their structure and working principle will not be elaborated further.

[0066] Step S4 also includes: after the twist strip 4 is installed, pre-compacting the assembly and the twist strip 4. By pre-compacting the assembly and the twist strip 4, each web 11 in the assembly is smoothly connected to the twist strip 4, thereby improving the laying quality of the skin 2 and preventing wrinkles from appearing in the fibers of the skin 2.

[0067] Specifically, the cover plate is pressed against the outer surfaces of the multiple web plates 11 and multiple twist strips 4 of the assembly, and then a vacuum bag is placed over it for vacuum pre-compression. The cover plate extends along the profile of the skin 2 and is installed at the location of the skin 2. The cover plate with the vacuum bag and the assembly are placed in an autoclave for vacuum pre-compression. During the vacuum pre-compression process, the cover plate can squeeze and trim the multiple web plates 11 and twist strips 4 to ensure the smoothness of the assembly and improve the laying quality of the skin 2.

[0068] In step S8, after unpacking, positioning holes are machined on the stiffened wall panel with the reinforcing layer stringer, and then demolding is performed. Machining the positioning holes before demolding avoids structural deformation of the stiffened wall panel with the reinforcing layer stringer and improves the machining accuracy of the positioning holes.

[0069] Step S8 is followed by step S9: the stiffened panel with the reinforcing girder is transferred to a milling fixture for finishing. After the stiffened panel with the reinforcing girder is detached from the panel forming fixture 10 and the soft mold fixture 20, it still needs to be finished by machining, which improves the surface quality and dimensional accuracy of the stiffened panel with the reinforcing girder. For example, after the stiffened panel with the reinforcing girder is installed in the milling fixture, the milling fixture is installed on a five-axis machine tool for finishing. The above-mentioned milling fixture and five-axis machine tool are all conventional fixtures and processing equipment, and will not be described in detail here.

[0070] The above embodiments merely illustrate the basic principles and characteristics of the present invention. The present invention is not limited to the above embodiments. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A reinforced wall panel with a reinforcing truss, characterized in that, include: The stringer (1) includes a web (11) and a flange (12). The flange (12) is provided at both ends of the web (11) along the width direction so that the stringer (1) is U-shaped. The web (11) and the corresponding flange (12) are respectively provided with rounded transition portions (13). Skin (2), along the profile direction of the skin (2), multiple stringers (1) are arranged side by side to form an assembly, and the skin (2) is attached to the outer surface of multiple web plates (11) of the assembly; The reinforcing layer (3) is sandwiched between the two adjacent flange strips (12) in two adjacent stringers (1). The first end (31) of the reinforcing layer (3) facing the web plate (11) is spaced apart from the skin (2). The first end (31) is attached to any one of the two adjacent rounded transition portions (13), so that the two adjacent rounded transition portions (13) in the two adjacent stringers (1) in the assembly form a triangular area (5). Twisted strips (4), each of the triangular regions (5) is filled with twisted strips (4), the stringer (1), the skin (2), the reinforcing layer (3) and the twisted strips (4) are connected together by a co-curing process.

2. The reinforced wall panel with a reinforcing layer stringer according to claim 1, characterized in that, The second end of the reinforcing layer (3) away from the web (11) is flush with the top end of the flange (12); the thickness of the first end (31) gradually decreases along the direction from the second end toward the first end (31).

3. The reinforced wall panel with a reinforcing layer stringer according to claim 1, characterized in that, The assembly also includes an L-shaped stringer (6), which includes a first plate (61) and a second plate (62) connected at an angle, and the first plate (61) and the second plate (62) are connected by a rounded corner transition. Along the profile direction of the skin (2), the two L-shaped stringers (6) are located on the outermost side of the assembly. The outer surface of each first plate (61) is attached to the skin (2), and the reinforcing layer (3) is sandwiched between each second plate (62) and the adjacent flange (12). The rounded transition area of ​​the L-shaped stringer (6) and the adjacent rounded transition part (13) form a triangular area (5).

4. A method for preparing a stiffened wall panel with a reinforcing layer stringer, characterized in that, The method for preparing the stiffened wall panel with a reinforcing truss as described in any one of claims 1-3 comprises the following steps: S1: The stringer (1), the reinforcing layer (3) and the twist strip (4) are prepared by prepreg. S2: Part of the stringer (1) is installed at the hard mold position of the wall panel forming fixture (10), and multiple reinforcing layers (3) are respectively attached to the outer side of the flange (12) of the stringer (1) at the hard mold position, and the first end (31) of the reinforcing layer (3) is attached to the outer side of the corresponding rounded transition part (13). S3: Another part of the stringers (1) are installed at the soft mold position of the wall panel forming fixture (10), and the hard mold position and the soft mold position are alternately arranged along the profile direction of the skin (2) so that multiple stringers (1) are arranged side by side to form the assembly; S4: The plurality of twisted strips (4) are respectively filled into the corresponding triangular regions (5); S5: The skin (2) is laid on the outer surface of the web (11) of the assembly to form a preform; S6: Sequentially lay an isolation mold, a breathable felt, and a vacuum bag on the outer surface of the preform, and then paste the vacuum bag together; S7: The preform enters the autoclave for curing and molding; S8: Remove the bag and demold the cured preform.

5. The method for preparing the stiffened wall panel with a reinforcing layer stringer according to claim 4, characterized in that, In step S1, the stringer (1) installed at the hard mold position is prepared by a hard mold tooling, and the stringer (1) installed at the soft mold position is prepared by a soft mold tooling (20). The twist strip (4) is extruded and formed by a die tooling after the prepreg is fed and rolled.

6. The method for preparing the stiffened wall panel with a reinforcing layer stringer according to claim 5, characterized in that, In step S2, the stringer (1) prepared by the soft mold tooling (20) and the corresponding soft mold tooling (20) are installed together at the soft mold position.

7. The method for preparing a stiffened wall panel with a reinforcing layer stringer according to claim 4, characterized in that, Step S4 further includes: after the twist strip (4) is installed, the assembly and the twist strip (4) are pre-compacted.

8. The method for preparing a stiffened wall panel with a reinforcing layer stringer according to claim 7, characterized in that, The cover plate is pressed against the outer surface of the multiple web plates (11) of the assembly and the multiple twist strips (4), and then the vacuum bag is put on for vacuum pre-compaction.

9. The method for preparing a stiffened wall panel with a reinforcing layer stringer according to claim 4, characterized in that, In step S8, after unpacking, positioning holes are machined on the stiffened wall panel of the reinforcing truss with the reinforcing layer, and then demolding is performed.

10. The method for preparing a stiffened wall panel with a reinforcing layer stringer according to claim 4, characterized in that, Step S8 is followed by step S9: the stiffened wall panel with the reinforced stringer is transferred to a milling fixture for finishing.

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