Lightning protection skin structure of aircraft wing

Abstract

The invention discloses an aircraft wing lightning protection skin structure, specifically, a skin layer is sequentially covered with a resin adhesive layer, a conductive copper mesh layer and a protective coating, a conductive mesh can effectively capture and disperse lightning current and can also be tightly connected with a metal structure in a wing, and direct damage of lightning to the interior of an aircraft is avoided. The resin adhesive layer contains the conductive filler, so that the lightning current dispersing capability of the skin is further improved, the lightning protection capability of the aircraft wing is improved, and the safety performance and the reliability of the aircraft are improved.

Description

Technical Field

[0001] The invention belongs to the field of aircraft design and relates to a skin structure for protecting an aircraft wing from lightning strikes. Background Art

[0002] With the rapid development of the aviation industry, the ability of aircraft to fly under complex meteorological conditions is becoming increasingly important. Among them, lightning strikes, as a common natural phenomenon, pose a serious threat to the safe flight of aircraft. Especially in areas where lightning strikes frequently occur, aircraft are very susceptible to lightning strikes during flight, which may not only cause damage to the aircraft structure, but also affect the aircraft's electrical system, causing serious flight accidents.

[0003] Aircraft skin is a dimensional component that surrounds the aircraft frame structure and is fixed to the frame with adhesives or rivets to form the aircraft's aerodynamic shape. The structure of the aircraft skin has a significant impact on the performance of the aircraft wing. Therefore, designing a skin structure for aircraft wing lightning protection is of great significance for improving the safety and reliability of the aircraft. Summary of the invention

[0004] The present invention provides a skin structure for protecting an aircraft wing from lightning strikes. By covering a conductive copper mesh layer on the surface of the skin layer, the lightning current can be effectively captured and dispersed, thereby improving the lightning protection capability of the aircraft wing and thus improving the safety performance and reliability of the aircraft.

[0005] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a skin structure for lightning protection of aircraft wing, characterized in that the skin structure comprises from bottom to top: a skin layer, the skin layer is cut into a wing shape by a carbon fiber composite material plate, and the surface is cleaned, polished and coated with a surface treatment agent.

[0006] A resin adhesive layer is coated on the surface of the skin layer through a coating process, and the resin adhesive layer is a polyimide resin or an epoxy resin.

[0007] A conductive copper mesh layer is covered on the resin adhesive layer through a hot pressing process, and then the conductive copper mesh layer is fully combined with the resin adhesive layer by controlling the pressure and temperature; the layer density of the conductive copper mesh is designed according to the characteristics of lightning strikes to ensure effective dispersion and conduction of lightning strike energy.

[0008] The protective coating is formed by spraying the protective coating evenly on the surface of the overall structure of the lightning protection skin using professional spraying equipment.

[0009] Preferably, the error between the shape of the skin layer and the shape of the wing is controlled within 5%.

[0010] Preferably, the resin adhesive layer uses polyimide resin or epoxy resin as a base material, and is added with conductive fillers of carbon nanotubes.

[0011] Preferably, it is characterized in that the conductive filler is stone black or carbon black.

[0012] Preferably, the surface density of the conductive copper mesh layer is 107 g / m 2 or 109g / m 2 .

[0013] Preferably, the thickness of the conductive copper mesh layer is 0.075 mm or 0.05 mm.

[0014] Preferably, the protective coating is made of weather-resistant material.

[0015] Beneficial effects of the present invention: The aircraft wing lightning protection structure design method of the present invention has the following advantages and effects: 1. The present invention can effectively capture and disperse lightning current and improve the lightning protection capability of the aircraft wing by covering the surface of the skin layer with a conductive copper mesh layer.

[0016] 2. The present invention further improves the lightning protection capability of the skin by adding conductive fillers to the resin adhesive layer material, thereby reducing the damage caused by lightning to the aircraft structure and electrical system.

[0017] 3. The skin layer composite materials used in the present invention have good durability and stability. The prepared skin has good durability and long service life and can maintain excellent lightning protection performance during long-term use.

[0018] 4. The lightning protection skin structure provided by the present invention is simple and easy to understand, convenient to construct, easy to promote, and easy to promote and apply in the field of aircraft manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 Shown is a complete structural diagram of the present invention; In the figure, 1-skin layer, 2-resin glue layer, 3-conductive copper mesh layer, 4-protective coating Figure 2 Shown is the D waveform current applied in the experimental test of the present invention; Figure 3Shown is the B waveform current applied in the experimental test of the present invention; Figure 4 Shown is the C* waveform current applied in the experimental test of the present invention. DETAILED DESCRIPTION

[0021] The technical scheme of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only exemplary descriptions and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect. Example 1

[0022] Please refer to Figure 1 In this embodiment, the present invention provides an aircraft wing lightning protection structure, the specific structure is as follows: aircraft skin layer 1, the skin layer 1 is a carbon fiber composite material sheet cut into a wing shape by a CNC water cutting machine, and surface treatment is performed to improve the bonding performance of the skin layer 1. The specific surface treatment includes cleaning the surface, grinding and applying a surface treatment agent. The shape error of the skin layer 1 and the wing shape should be controlled within 5%. The skin layer 1 is laid on the wing surface to provide external protection and aerodynamic performance of the wing.

[0023] A layer of resin adhesive layer 2 is coated on the surface of the aircraft skin layer 1 through a coating process. The resin adhesive layer 2 is prepared by selecting epoxy resin as a base material and black as an additive material to ensure that the resin adhesive layer 2 is evenly covered on the surface of the skin layer 1 to form a good bonding layer. The thickness of the resin adhesive layer 2 is 0.05 mm. The resin adhesive layer 2 is used to enhance the bonding force and lightning protection performance of the conductive copper mesh.

[0024] A conductive copper mesh structure is covered on the surface of the resin adhesive layer 2 to form a conductive copper mesh layer 3. The specific covering method is: firmly combined with the resin adhesive layer through a hot pressing process, the pressure is 1Mpa, and the temperature is controlled at 120°C to ensure the conductivity and structural stability of the conductive copper mesh. The thickness of the conductive copper mesh layer 3 is 0.05mm and the surface density is 195g / m 2 The shape and surface density of the conductive copper mesh layer 3 are optimized according to the geometric shape of the wing and the characteristics of lightning strikes to ensure the effective dispersion and conduction of lightning strike energy and reduce the impact of lightning strikes on the wing structure.

[0025] A protective coating 4 is evenly sprayed on the surface of the conductive copper mesh 3 using professional spraying equipment to ensure that the protective coating covers evenly and completely. The protective coating 4 is made of polypropylene and has a thickness of 0.03 mm. The protective coating 4 is used to prevent corrosion and improve the durability of the wing.

[0026] The entire lightning protection structure is placed in a vacuum curing device for curing to ensure that each layer is firmly bonded.

[0027] The prepared aircraft wing lightning protection structure is inspected to ensure that the bonding between the layers is firm, the surface coating is smooth, and there are no defects such as bubbles and cracks. Example 2

[0028] Please refer to Figure 1 In this embodiment, the present invention provides an aircraft wing lightning protection structure, the specific structure of which is as follows: an aircraft skin layer 1, the skin layer 1 is a carbon fiber composite material sheet cut into a wing shape by a CNC water cutting machine, and surface treatment is performed to improve the bonding performance of the skin layer 1. The specific surface treatment includes cleaning the surface, grinding and coating a surface treatment agent. The shape error of the skin layer 1 and the wing shape should be controlled within 5%.

[0029] A layer of resin adhesive layer 2 is coated on the surface of the aircraft skin layer 1 through a coating process. The resin adhesive layer 2 is prepared with polyimide resin as a base material and carbon black as an additive. It is ensured that the resin adhesive layer 2 is evenly covered on the surface of the skin layer 1 to form a good bonding layer. The thickness of the resin adhesive layer 2 is 0.1 mm.

[0030] A conductive copper mesh structure is covered on the surface of the resin adhesive layer 2 to form a conductive copper mesh layer 3. The specific covering method is: firmly combined with the resin adhesive layer through a hot pressing process, the pressure is 2Mpa, and the temperature is controlled at 150°C to ensure the conductivity and structural stability of the conductive copper mesh. The thickness of the conductive copper mesh layer 3 is 0.075mm and the surface density is 107g / m 2 .

[0031] A layer of protective coating 4 is evenly sprayed on the surface of the conductive copper mesh 3 using professional spraying equipment to ensure that the protective coating covers evenly and completely. The protective coating 4 is made of polypropylene and has a thickness of 0.1 mm.

[0032] The entire lightning protection structure is placed in a vacuum curing device for curing to ensure that each layer is firmly bonded.

[0033] The prepared aircraft wing lightning protection structure is inspected to ensure that the bonding between the layers is firm, the surface coating is smooth, and there are no defects such as bubbles and cracks.

[0034] Please refer to Figure 2-Figure 4 The lightning protection structures of Example 1 and Example 2 were subjected to a lightning impulse simulation full-wave test, and the D waveform, B waveform, and C* waveform currents were applied to the lightning protection structures. First, a voltage waveform (D waveform) simulating lightning discharge was applied, and then a constant current was applied to further test the withstand voltage performance of the equipment and calculate the damage area of ​​each layer of the lightning protection structure. The damage area of ​​each layer is shown in Table 1 Table 1 Damage area of ​​each layer Protective coating (mm×mm) Conductive copper mesh layer (mm×mm) Resin layer (mm×mm) Skin layer (mm×mm) Example 1 1553.5 5803.77 22.80 0 Example 2 632.4 2375.52 8.12 0 It can be seen from Table 1 that under the application of the same D waveform, B waveform, and C* waveform current, there is no damage area in the skin layer of Example 1 and Example 2, that is, there is no direct damage to the wing structure, and the damage area of ​​the protective coating, conductive copper mesh layer and resin layer of the lightning protection structure of Example 2 is significantly reduced by more than 2 times than the damage area of ​​each layer in Example 1, which shows that the lightning protection structure of Example 2 has better lightning protection effect.

[0035] It can be seen from the embodiments that after the overall lightning protection structure is assembled, a complete wing lightning protection structure is formed, which can effectively conduct lightning current when struck by lightning and greatly reduce the direct damage to the wing structure caused by lightning.

Claims

1. A skin structure for protecting an aircraft wing from lightning strike, characterized in that: The skin structure includes, from bottom to top, a skin layer, which is cut into a wing shape using a carbon fiber composite material sheet, and the surface is cleaned, polished, and coated with a surface treatment agent; A resin adhesive layer, wherein the resin adhesive layer is coated on the surface of the skin layer through a coating process, and the resin adhesive layer is a polyimide resin or an epoxy resin; A conductive copper mesh layer, wherein the conductive copper mesh layer is covered on the resin adhesive layer by a hot pressing process, and then the conductive copper mesh layer is fully combined with the resin adhesive layer by controlling the pressure and temperature, and the layer density of the conductive copper mesh layer is designed according to the characteristics of lightning strikes to ensure effective dispersion and conduction of lightning strike energy; The protective coating is formed by spraying the protective coating evenly on the surface of the overall structure of the lightning protection skin using professional spraying equipment.

2. The skin structure according to claim 1, characterized in that: The shape error of the skin layer and the wing shape is controlled within 5%.

3. The skin structure according to claim 1, characterized in that: The resin adhesive layer is based on polyimide resin or epoxy resin and is added with conductive fillers of carbon nanotubes.

4. The skin structure according to claim 3, characterized in that: The conductive filler is stone black or carbon black.

5. The skin structure according to claim 1, characterized in that: The surface density of the conductive copper mesh layer is 107 g / m 2 or 109g / m 2 .

6. The skin structure according to claim 1, characterized in that: The thickness of the conductive copper mesh layer is 0.075 mm or 0.05 mm.

7. The skin structure according to claim 1, characterized in that: The protective coating is made of weather-resistant material.

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