A variable stiffness sealing structure with tension-shear composite connection and its optimization method

Abstract

The present application belongs to the technical field of aircraft wing strength design, and particularly relates to a variable stiffness sealing structure and an optimization method of a tension-shear composite connection, comprising: a sealing structure, a grooved strip plate (3) and a supporting structure; the supporting structure comprises a plurality of supporting partitions (1) distributed along the span direction, the grooved strip plate (3) connects the ends of the plurality of supporting partitions (1) along the span direction, and forms a frame structure with the supporting partitions (1); the grooved strip plate (3) comprises a bottom plate and a vertical plate, the bottom plate is connected to the supporting partition (1); the vertical plate is perpendicular to the bottom plate; the sealing structure comprises a sealing plate (4) and vertical ribs (41), the sealing plate (4) is divided into a fixed section at the front section and a cantilever section at the rear section, the vertical ribs (41) are located between the fixed section and the cantilever area; the fixed section is fixedly connected to the bottom plate of the grooved strip plate (3), the vertical ribs (41) are fixedly connected to the vertical plate of the grooved strip plate (3), and the cantilever section of the sealing structure overlaps the rudder surface (2).

Description

Technical Field

[0001] The present application belongs to the technical field of aircraft wing strength design, and in particular relates to a variable stiffness sealing structure of a tension-shear composite connection and an optimization method. Background Art

[0002] Aircraft with sealing requirements often feature a cantilever beam flat-plate structure, connected to the supporting structure via a strap. This structure, subject to repeated large deformations, causes the connecting strap to bend repeatedly, which can easily lead to fatigue cracks. Furthermore, the connecting bolts are subjected to high pullout forces and high extrusion loads along the hole edges, easily damaging both the bolts and the nail holes. Furthermore, due to the low rigidity of the fixed end, the cantilever beam flat-plate structure often has excessive deformation capacity but insufficient load-bearing capacity, resulting in a weak sealing function. Summary of the Invention

[0003] In order to solve the above problems, the present application provides a variable stiffness sealing structure of a tension-shear composite connection, comprising:

[0004] Sealing structure, trough strip plate (3) and supporting structure;

[0005] The supporting structure comprises a plurality of supporting partitions (1) distributed along the span direction, a trough-shaped strip plate (3) connecting the ends of the plurality of supporting partitions (1) along the span direction, and forming a frame structure with the supporting partitions (1), the trough-shaped strip plate (3) comprising a bottom plate and a vertical plate, the bottom plate being connected to the supporting partition (1); the vertical plate being perpendicular to the bottom plate;

[0006] The sealing structure comprises a sealing plate (4) and vertical ribs (41). The sealing plate (4) is divided into a fixed section at the front and a cantilever section at the rear. The vertical ribs (41) are located between the fixed section and the cantilever section. The fixed section is fixedly connected to the bottom plate of the trough-shaped strip plate (3). The vertical ribs (41) are fixedly connected to the vertical plate of the trough-shaped strip plate (3). The cantilever section of the sealing structure overlaps the rudder surface (2).

[0007] In some optional embodiments, it further comprises a wall panel, which is installed on the frame structure formed by the supporting partition plate (1) and the grooved strip plate (3).

[0008] In some optional embodiments, the sealing structure is made of composite material.

[0009] In some optional embodiments, the sealing structure is a curved plate structure with variable thickness.

[0010] In some optional embodiments, the supporting partition (1) is an L-shaped partition or a T-shaped partition.

[0011] In some optional embodiments, the supporting partition (1) is connected to the wall panel by bolts.

[0012] In some optional embodiments, the sealing structure and the grooved strip plate (3) are connected by bolts, wherein the sealing structure and the grooved butt strip plate are connected by two rows of bolts, the inner and outer rows, and the side bolts are the main force transmission path, which converts most of the out-of-plane tension into in-plane shear force, greatly reducing the risk of fracture of the sealing plate connection area and the bolt head. The free end is in the form of a curved plate with variable thickness, which is overlapped on the front edge of the rudder surface. According to the cantilever beam theory, it can make the force uniform and reduce the risk of damage.

[0013] The supporting partition is a fixed structure, and the sealing structure is connected to it through a grooved butt joint plate. The grooved butt joint plate has a large cross-sectional inertia moment, which effectively enhances the bending resistance of the structure.

[0014] In some optional embodiments, the thickness of the cantilever section of the sealing structure gradually decreases along the chord direction, and a specific method for obtaining the dimensional parameters thereof includes:

[0015] Establish the finite element analysis model of the cantilever section and the rudder skin;

[0016] Create motion conditions for the finite element analysis model and apply aerodynamic loads to obtain the position where the contact force between the cantilever section and the rudder skin is maximum;

[0017] The design parameters of the cantilever section are obtained with the constraint that the contact force between the cantilever section at the position with the maximum contact force and the rudder skin is not greater than a set value and with the goal of minimizing the strain of the cantilever section;

[0018] The material and shape of the sealing structure are selected based on the design parameters.

[0019] Preferably, the cantilever section is divided into a plurality of zones along the chord direction, the design parameters include the zone thickness of each zone, and based on the determined zone thickness and with the minimum weight as the goal, the ply ratio of the isodirectional fabric and the unidirectional tape in each zone is determined.

[0020] The advantages of this application include: the sealing structure has two rows of bolts in the connection area, and the side bolts are the main force transmission path, which converts most of the out-of-plane tension into in-plane shear force, greatly reducing the risk of bolt head fracture in the sealing plate connection area; the sealing structure has high connection stiffness at the fixed end, which enhances the sealing structure's ability to resist deformation and effectively improves its bearing capacity; the grooved butt joint plate has a large cross-sectional inertia moment, which effectively enhances the structure's bending resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a cross-sectional view of a variable stiffness sealing structure of a tension-shear composite connection according to a preferred embodiment of the present application;

[0022] Figure 2 It is a three-dimensional diagram of a variable stiffness sealing structure of a tension-shear composite connection according to a preferred embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to make the technical solution and its advantages of the present application clearer, the technical solution of the present application will be described in further detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of the present application and are only used to explain the present application, not to limit the present application. It should be noted that, for ease of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0024] In addition, it should be noted that, unless otherwise clearly stipulated and limited, the words "install", "connect", "connect" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, an indirect connection through an intermediate medium, or a connection between two components. Technical personnel in the field can understand their specific meanings in this application according to the specific circumstances.

[0025] like Figure 1-Figure 2 As shown, in order to solve the above problems, the present application provides a variable stiffness sealing structure of a tension-shear composite connection, comprising:

[0026] Sealing structure, trough strip plate (3) and supporting structure;

[0027] The supporting structure comprises a plurality of supporting partitions (1) distributed along the span direction, a trough-shaped strip plate (3) connecting the ends of the plurality of supporting partitions (1) along the span direction, and forming a frame structure with the supporting partitions (1), the trough-shaped strip plate (3) comprising a bottom plate and a vertical plate, the bottom plate being connected to the supporting partition (1); the vertical plate being perpendicular to the bottom plate;

[0028] The sealing structure comprises a sealing plate (4) and vertical ribs (41). The sealing plate (4) is divided into a fixed section at the front and a cantilever section at the rear. The vertical ribs (41) are located between the fixed section and the cantilever section. The fixed section is fixedly connected to the bottom plate of the trough-shaped strip plate (3). The vertical ribs (41) are fixedly connected to the vertical plate of the trough-shaped strip plate (3). The cantilever section of the sealing structure overlaps the rudder surface (2).

[0029] Preferably, it further comprises a wall panel, which is installed on the frame structure formed by the supporting partition plate (1) and the grooved strip plate (3).

[0030] Preferably, the sealing structure is made of composite material.

[0031] Preferably, the sealing structure is a curved plate structure with variable thickness.

[0032] Preferably, the supporting partition (1) is an L-shaped partition or a T-shaped partition.

[0033] Preferably, the supporting partition (1) is connected to the wall panel by bolts.

[0034] Preferably, the sealing structure and the grooved strip plate (3) are connected by bolts.

[0035] Preferably, the thickness of the cantilever section of the sealing structure gradually decreases along the chord direction, and the specific method for obtaining the size parameters thereof includes:

[0036] Establish finite element analysis models of the cantilever section and rudder skin;

[0037] Create motion conditions for the finite element analysis model and apply aerodynamic loads to obtain the position where the contact force between the cantilever section and the rudder skin is maximum;

[0038] The design parameters of the cantilever section are obtained with the constraint that the contact force between the cantilever section at the position with the maximum contact force and the rudder skin is not greater than a set value and with the goal of minimizing the strain of the cantilever section;

[0039] The material and shape of the sealing structure are selected based on the design parameters.

[0040] Preferably, the cantilever section is divided into a plurality of zones along the chord direction, the design parameters include the zone thickness of each zone, and based on the determined zone thickness and with the minimum weight as the goal, the ply ratio of the isodirectional fabric and the unidirectional tape in each zone is determined.

[0041] The advantages of this application include: the sealing structure has two rows of bolts in the connection area, and the side bolts are the main force transmission path, which converts most of the out-of-plane tension into in-plane shear force, greatly reducing the risk of bolt head fracture in the sealing plate connection area; the sealing structure has high connection stiffness at the fixed end, which enhances the sealing structure's ability to resist deformation and effectively improves its bearing capacity; the grooved butt joint plate has a large cross-sectional inertia moment, which effectively enhances the structure's bending resistance.

[0042] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A variable stiffness sealing structure with a tension-shear composite connection, characterized in that: include: Sealing structure, trough strip plate (3) and supporting structure; The supporting structure comprises a plurality of supporting partitions (1) distributed along the span direction, a trough-shaped strip plate (3) connecting the ends of the plurality of supporting partitions (1) along the span direction, and forming a frame structure with the supporting partitions (1), the trough-shaped strip plate (3) comprising a bottom plate and a vertical plate, the bottom plate being connected to the supporting partition (1); the vertical plate being perpendicular to the bottom plate; The sealing structure comprises a sealing plate (4) and vertical ribs (41). The sealing plate (4) is divided into a fixed section at the front and a cantilever section at the rear. The vertical ribs (41) are located between the fixed section and the cantilever section. The fixed section is fixedly connected to the bottom plate of the trough-shaped strip plate (3). The vertical ribs (41) are fixedly connected to the vertical plate of the trough-shaped strip plate (3). The cantilever section of the sealing structure overlaps the rudder surface (2).

2. The variable stiffness sealing structure of the tension-shear composite connection according to claim 1, characterized in that: It also includes a wall panel, which is installed on a frame structure formed by the supporting partition plate (1) and the grooved strip plate (3).

3. The variable stiffness sealing structure of the tension-shear composite connection according to claim 1, characterized in that: The sealing structure is made of composite materials.

4. The variable stiffness sealing structure of the tension-shear composite connection according to claim 3, characterized in that: The sealing structure is a curved plate structure with variable thickness.

5. The variable stiffness sealing structure of the tension-shear composite connection according to claim 1, characterized in that: The supporting partition (1) is an L-shaped partition or a T-shaped partition.

6. The variable stiffness sealing structure of the tension-shear composite connection according to claim 2, characterized in that: The supporting partition (1) is connected to the wall panel via bolts.

7. The variable stiffness sealing structure of the tension-shear composite connection according to claim 1, characterized in that: The sealing structure and the grooved strip plate (3) are connected by bolts.

8. The variable stiffness sealing structure of the tension-shear composite connection according to claim 1, characterized in that: The thickness of the cantilever section of the sealing structure gradually decreases along the chord direction. The specific method for obtaining its size parameters includes: Establish finite element analysis models of the cantilever section and rudder skin; Create motion conditions for the finite element analysis model and apply aerodynamic loads to obtain the position where the contact force between the cantilever section and the rudder skin is maximum; The design parameters of the cantilever section are obtained with the constraint that the contact force between the cantilever section at the position with the maximum contact force and the rudder skin is not greater than a set value and with the goal of minimizing the strain of the cantilever section; The material and shape of the sealing structure are selected based on the design parameters.

9. The variable stiffness sealing structure of the tension-shear composite connection according to claim 8, characterized in that: The cantilever section is divided into a plurality of zones along the chord direction. The design parameters include the zone thickness of each zone. Based on the determined zone thickness and with the minimum weight as the goal, the ply ratio of the isodirectional fabric and the unidirectional tape in each zone is determined.

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