Anti-icing and de-icing surface structure for aircraft skin

Abstract

The invention relates to the technical field of aircraft anti-icing and de-icing devices, in particular to an anti-icing and de-icing surface structure for aircraft skin, which comprises a base body, a working area is arranged on the base body, an ice dredging layer is arranged on the working area, and the ice dredging layer comprises a structural net and an elastic layer arranged on the surface of the structural net. Elastic filling bodies are arranged in meshes of the structural net, and the elastic modulus of the structural net is larger than the elastic modulus of the elastic layer and the elastic filling bodies. According to the anti-icing and de-icing surface structure, by means of elastic deformation differences, ice bodies directionally generate cracks on the structure net, and the de-bonding strength of the ice bodies on the anti-icing and de-icing surface structure is reduced; when the anti-icing and deicing surface structure is subjected to high-strength wind pressure, the pressure can be concentrated on the longitudinal ridges and the transverse ridges of the structural net, the upper pressure bearing limit of the anti-icing and deicing surface structure is improved, the safety and stability of the micro-nano structure are kept by the anti-icing and deicing surface structure under the high-strength wind pressure, and the aircraft can achieve the stable anti-icing and deicing effect in the extreme flight environment.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft anti-icing devices, and in particular to an anti-icing surface structure for aircraft skin. Background Art

[0002] Aircraft icing is widely considered to be one of the major hazards of aviation. When an aircraft passes through clouds with icing meteorological conditions, supercooled water droplets in the clouds hit the windward side of the aircraft, causing ice to form on the surface of the aircraft's windward components (wings, windshields, tail fins, engine lips, pitot tubes, etc.), especially near the stagnation point. Ice on key aircraft components will seriously affect the aerodynamic performance of the aircraft, causing the aircraft's safety performance to drop rapidly. For example, ice on the leading edge of the wing and tail will change the aerodynamic shape of the aircraft to varying degrees, violate the aircraft design criteria, rapidly reduce lift, and rapidly increase drag, seriously affecting the aircraft's maneuverability and stability. Therefore, how to build an efficient anti-icing strategy has become an urgent problem to be solved during aircraft flight.

[0003] At present, the main anti-icing strategies include passive anti-icing methods and active anti-icing methods. Active deicing methods are generally physical methods (mechanical deicing or electric heating anti-icing) and chemical methods (spraying anti-icing agents such as salt water or ethylene glycol). Although they can solve the ice accumulation problem to a certain extent, they require a high price in terms of energy, manpower, and environment. In addition, active technologies are often difficult to implement due to environmental and energy constraints, complex surface structures, and other factors. Therefore, anti-icing technologies that do not require energy consumption (i.e., passive deicing technologies) have attracted widespread attention from researchers. Passive deicing technology is mainly based on the surface properties of materials and mainly includes two categories: one is to delay surface frost or ice formation by inhibiting nucleation, with super-hydrophobic surfaces as a typical representative, but its surface micro-nanostructure is extremely easy to be destroyed and difficult to use for a long time, and it can only inhibit ice formation to a certain extent, and cannot completely prevent ice; the other type of technology is called ice-repellent surface, which reduces the adhesion strength between ice and the surface, so that the ice layer can easily detach from the surface under the action of external forces (wind, self-gravity, etc.).

[0004] In the process of realizing the present invention, the applicant discovered that although the existing passive anti-icing technology can reduce the ice adhesion strength, it is limited by the surface micro-nano structure and the upper limit of the pressure is also reduced, resulting in the risk of the surface micro-nano structure that realizes the anti-icing function being easily damaged under high pressure. Summary of the invention

[0005] The purpose of the present invention is to provide an anti-icing surface structure for aircraft skin to solve the above technical problems existing in the prior art, which mainly includes the following contents: The present invention provides an anti-icing surface structure, comprising a substrate, a working area is arranged on the substrate, an ice-repelling layer is arranged on the working area, the ice-repelling layer comprises a structural net and an elastic layer arranged on the surface of the structural net, an elastic filling body is arranged in the mesh of the structural net, and the elastic modulus of the structural net is greater than the elastic modulus of the elastic layer and the elastic filling body.

[0006] Furthermore, the elastic layer and the elastic filling body are integrally arranged; And / or, the elastic layer and the elastic filler are respectively low surface energy modified polymer materials.

[0007] Furthermore, a column is arranged in the mesh, the column is located in the middle of the mesh, and the height of the column is less than the depth of the mesh.

[0008] Furthermore, the column is any one of a cylinder, a prism, and a cone, or a combination of at least two of them; And / or, the mesh is any one of a rectangle, a circle, an ellipse, a diamond, a triangle, or a combination of at least two of them.

[0009] Further, the structural net includes a plurality of longitudinal ridges and a plurality of transverse ridges; Multiple longitudinal ridges are arranged in parallel, the height of the longitudinal ridges is a, the width of the longitudinal ridges is b, the distance between two adjacent longitudinal ridges is c, and the ratio of a, b and c is 2~5:6:16~32; And / or, multiple transverse ridges are arranged in parallel, the height of the transverse ridge is x, the width of the transverse ridge is y, the interval between two adjacent transverse ridges is z, and the ratio of x, y and z is 2~5:6:16~32.

[0010] Furthermore, the height of the longitudinal ridges is 200 μm to 500 μm, and the height of the transverse ridges is 200 μm to 500 μm.

[0011] Furthermore, the structural net is provided with a windward section; Multiple longitudinal ridges are arranged in sequence along the windward direction, and the height of the longitudinal ridges in the windward section gradually decreases; Alternatively, a plurality of transverse ridges are arranged in sequence along the windward direction, and the height of the transverse ridges in the windward section gradually decreases.

[0012] Furthermore, the height gradually decreases by 50 μm to 150 μm.

[0013] Furthermore, it comprises a wing shell, and the windward section is arranged on the windward surface of the wing shell.

[0014] Compared with the prior art, the present invention has at least the following technical effects: When the ice body on the anti-icing surface structure of the present invention is subjected to pressure, the elastic deformation difference is used to cause cracks in the ice body at the longitudinal ridges and / or transverse ridges of the structural net, and a crack network corresponding to the structural net is quickly formed in a short time, thereby reducing the debonding strength of the ice body on the anti-icing surface structure; and when the anti-icing surface structure is subjected to high-intensity wind pressure, the pressure will be concentrated on the longitudinal ridges and transverse ridges of the structural net. Since the longitudinal ridges and transverse ridges of the structural net are criss-crossed and connected, they can provide support to each other, and then the pressure can be dispersed to the entire structural net, increasing the force-bearing area, thereby improving the upper pressure limit of the anti-icing surface structure, allowing the anti-icing surface structure to maintain the safety and stability of the micro-nano structure under high-intensity wind pressure, and the aircraft can achieve a stable anti-icing effect in extreme flight environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments of the present invention or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a structural schematic diagram of the anti-deicing surface structure of the present invention; Figure 2 It is a schematic diagram of the explosion structure of the anti-deicing surface structure of the present invention; Figure 3 It is a schematic diagram of the structure of the substrate and the structural network of the present invention; Figure 4 is a cross-sectional view of the anti-deicing surface structure of the present invention; Figure 5 is a cross-sectional view of another structure of the anti-deicing surface structure of the present invention; Figure 6 is a schematic structural diagram of the wing shell of the present invention; In the figure, 10, base; 20, structural net; 210, longitudinal ridge; 220, transverse ridge; 30, elastic layer; 40, elastic filling body; 50, column; 60, windward section; 90, wing shell; 910, windward surface. DETAILED DESCRIPTION

[0017] The following description provides many different embodiments or examples for implementing different features of the present invention. The components and arrangements described in the following specific examples are only used to simplify the present invention and are only used as examples, not to limit the present invention.

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0019] Existing passive anti-icing technologies, such as a deicing heterogeneous surface structure and a preparation method thereof disclosed in Chinese Patent Publication No. CN118238992B, although the ice adhesion strength is reduced by a column in the ice-repellent layer, are limited by the surface micro-nano structure. When applied to an aircraft to withstand wind pressure, the stress will be concentrated on the column, and the column itself is a micron-level microstructure with a low upper pressure limit, which may cause the column to be damaged due to excessive wind pressure and stress concentration, causing the anti-icing microstructure to fail. In order to solve the technical problem that the existing anti-icing microstructure is prone to fail due to excessive pressure, the present invention provides a high-strength anti-icing surface structure, a wing and an aircraft composed of a structural net, an elastic filler and an elastic layer, as shown in the following embodiments.

[0020] Example 1 An anti-deicing surface structure for aircraft skin, such as Figure 1~Figure 4 As shown, it includes a substrate 10, on which a working area is arranged, and the working area can be concave on the outer surface of the substrate 10, or the working area can be protruding from the outer surface of the substrate 10; an ice-phobic layer is arranged on the working area, and the ice-phobic layer includes a structural net 20 and an elastic layer 30 arranged on the surface of the structural net 20, and an elastic filling body 40 is arranged in the mesh of the structural net 20, and the elastic modulus of the structural net 20 is greater than the elastic modulus of the elastic layer 30 and the elastic filling body 40.

[0021] The adhesion strength of ice on the surface of the material is not only closely related to the molecular force between the interfaces, but also closely related to the structural characteristics of the surface of the material. In this embodiment, the elastic filler 40 is filled in the structural net 20, and the elastic layer 30 is arranged on the surface of the structural net 20, so that the outer surface of the ice-phobic layer has a complete low apparent elastic modulus, which is conducive to the sliding and debonding of the ice under a small shear force. The interior of the ice-phobic layer is composed of the structural net 20 with a relatively high elastic modulus and the elastic filler 40 with a low elastic modulus. When the ice is subjected to pressure, the elastic deformation of the elastic layer 30 corresponding to the structural net 20 is different from the elastic deformation of the elastic layer 30 corresponding to the elastic filler 40. The difference in elastic deformation is used to allow the ice to be deformed at the longitudinal ridges 210 and / or transverse ridges 220 of the structural net 20. Cracks will occur, and subsequent cracks will extend along the longitudinal ridges 210 and transverse ridges 220, quickly forming a crack network corresponding to the structural net 20 in a short time, thereby reducing the debonding strength of the ice body on the anti-icing surface structure; when the anti-icing surface structure is subjected to high-intensity wind pressure, the pressure will be concentrated on the longitudinal ridges 210 and transverse ridges 220 of the structural net 20. Since the longitudinal ridges 210 and transverse ridges 220 of the structural net 20 are criss-crossed and connected, they can provide support to each other, and then the pressure can be dispersed to the entire structural net 20, increasing the force-bearing area, thereby improving the upper limit of the pressure-bearing capacity of the anti-icing surface structure, allowing the anti-icing surface structure to maintain the safety and stability of the micro-nano structure under high-intensity wind pressure, so that the aircraft can achieve a stable anti-icing effect in extreme flight environments.

[0022] It should be noted that the base 10 is the shell of the anti-icing object, and the anti-icing object can be aircraft, automobiles, ships and other equipment with anti-icing requirements. In this embodiment, the deicing object is an aircraft. The base can be configured as a shell containing a functional module for realizing mechanical deicing, or it can be a separate shell. The shape of the shell is not specifically limited in this embodiment (the functional module for realizing mechanical deicing is a prior art and will not be elaborated here).

[0023] In order to ensure the structural stability between the elastic layer 30 and the elastic filling body 40 , the elastic layer 30 and the elastic filling body 40 may be integrated, that is, the elastic layer 30 and the elastic filling body 40 may be made of the same polymer material.

[0024] In some embodiments, the elastic layer 30 and the elastic filling body 40 may be made of different materials respectively. Specifically, the elastic filling body 40 may be filled into the mesh first, and then coated with the elastic layer 30 .

[0025] In order to reduce the surface ice adhesion strength of the anti-icing surface structure, the elastic layer 30 and the elastic filler 40 can be respectively made of low surface energy modified polymer materials. Exemplarily, the polymer material raw materials include component A, component B and component C in a mass ratio of 10:0.5~2:0.04~0.08, wherein component A is polydimethylsiloxane, component B is tetraethyl orthosilicate or 1H,1H,2H,2H-perfluorodecyltrimethylsilane, and component C is dibutyltin dilaurate. Component A, component B and component C can be used to make the elastic layer 30 and the elastic filler 40 after being stirred and mixed evenly.

[0026] In order to improve the upper pressure limit of the anti-icing surface structure, a column 50 can be set in the mesh, the column 50 is located in the middle of the mesh, and the height of the column 50 is less than the depth of the mesh. Under normal conditions, the height of the column 50 in the mesh is less than the depth of the mesh, which has little effect on the effect of using elastic deformation difference to achieve crack orientation. Under high pressure, the pressure can be transmitted to the column 50 through the elastic layer 30 and the elastic filler 40 that are deformed to a certain limit. The column 50 and the structural net 20 share the pressure together, increasing the pressure-bearing area and reducing the pressure on the structural net 20, thereby improving the upper pressure limit of the anti-icing surface structure. On the basis of achieving anti-icing, the anti-icing surface structure maintains structural safety and stability under high pressure. Preferably, the column 50 is any one of a cylinder, a prism, and a cone, or a combination of at least two of them.

[0027] In some embodiments, the mesh may be set to be any one of a rectangle, a circle, an ellipse, a diamond, a triangle, or a combination of at least two of them; in this embodiment, the mesh is preferably a square.

[0028] In order to take into account both the anti-deicing effect and the pressure bearing effect, the structural net 20 may be provided to include a plurality of longitudinal ridges 210 and a plurality of transverse ridges 220; Multiple longitudinal ridges 210 are arranged in parallel, the height of the longitudinal ridge 210 is a, the width of the longitudinal ridge 210 is b, the distance between two adjacent longitudinal ridges 210 is c, and the ratio of a, b and c is 2~5:6:16~32; The plurality of transverse ridges 220 are arranged in parallel, the height of the transverse ridge 220 is x, the width of the transverse ridge 220 is y, the interval between two adjacent transverse ridges 220 is z, and the ratio of x, y and z is 2-5:6:16-32.

[0029] Specifically, the height of the longitudinal ridge 210 is 200 μm to 500 μm, and the height of the transverse ridge 220 is 200 μm to 500 μm. In this example, preferably, the height of the longitudinal ridge 210 is 500 μm, and the height of the transverse ridge 220 is 500 μm. Correspondingly, the ratio of a, b and c is 5:6:16, and the ratio of x, y and z is 5:6:16.

[0030] When the anti-deicing surface structure is applied to an aircraft, the surface of the aircraft has a camber or curved surface in a local area, such as the front windward area of ​​the wing. To adapt to the front windward area of ​​the wing, a windward section 60 may be provided on the structural net; If multiple longitudinal ridges 210 are arranged in sequence along the windward direction, such as Figure 5 As shown, the height of the longitudinal ridges 210 in the windward section 60 can be gradually reduced, and the gradually reduced longitudinal ridges 210 form an inclined surface, thereby increasing the contact angle between the positive wind pressure and the inclined surface, so that the wind pressure can exert a greater shear force on the ice body on the windward surface 910, making it easier for the ice body on the windward surface 910 to fall off. At the same time, the longitudinal ridges 210 and the transverse ridges 220 are staggered to provide support to each other, so that the anti-icing surface structure on the windward surface 910 of the wing can withstand greater wind pressure without being damaged, thereby ensuring that the anti-icing function is stably implemented under high pressure.

[0031] If multiple transverse ridges 220 are arranged in sequence along the windward direction, the height of the transverse ridges 220 in the windward section 60 can be gradually reduced. The gradually reduced transverse ridges 220 form an inclined surface, thereby increasing the contact angle between the positive wind pressure and the inclined surface, so that the wind pressure can exert a greater shear force on the ice body on the windward surface 910, making it easier for the ice body on the windward surface 910 to fall off. At the same time, the longitudinal ridges 210 and the transverse ridges 220 are staggered to provide support to each other, so that the anti-icing surface structure on the windward surface 910 of the wing can withstand greater wind pressure without being damaged, thereby ensuring that the anti-icing function is stably implemented under high pressure.

[0032] In some embodiments, in order to adapt to the presence of camber or curved surfaces on the surface of the aircraft in a local area, the amplitude of the gradual decrease in the height of the longitudinal ridges 210 or the transverse ridges 220 in the structural net 20 can be set to 50 μm~150 μm. For example, in the front windward area of ​​the wing, if multiple longitudinal ridges 210 are arranged in sequence along the windward direction, the height of the longitudinal ridges 210 in the windward section 60 can be gradually reduced by 150 μm, and the height is reduced twice. Three longitudinal ridges 210 constitute a windward section. Correspondingly, the heights of the three longitudinal ridges 210 are 500 μm, 350 μm, and 200 μm, respectively, and the transverse ridges 220 are 200 μm, 200 μm, and 200 μm, respectively. 0 then maintains the same height as the connected longitudinal ridge 210, and the height of the transverse ridge 220 between the two longitudinal ridges 210 transitions smoothly; as another example, in the leading windward area of ​​the wing, if multiple transverse ridges 220 are arranged in sequence along the windward direction, the height of the transverse ridge 220 in the windward section can be gradually reduced by 50 μm, and the height is reduced once. Two transverse ridges 220 constitute a windward section 60, and the heights of the two transverse ridges 220 are 500 μm and 450 μm respectively, while the longitudinal ridge 210 maintains the same height as the connected transverse ridge 220, and the height of the longitudinal ridge 210 between the two transverse ridges 220 transitions smoothly.

[0033] In some embodiments, Figure 6As shown, it includes a wing shell 90, on which the anti-icing surface structure in Example 1 is arranged, and the windward section 60 is arranged on the windward surface 910 of the wing shell 90, and multiple windward sections 60 can be arranged on the windward surface 910 according to the area of ​​the windward surface 910.

[0034] If multiple longitudinal ridges 210 are arranged in sequence along the windward direction of the wing shell 90, the height of the longitudinal ridges 210 in the windward section 60 can be gradually reduced. The gradually reduced longitudinal ridges 210 form an inclined surface, thereby increasing the contact angle between the positive wind pressure and the inclined surface, so that the wind pressure can exert a greater shear force on the ice body on the windward surface 910, making it easier for the ice body on the windward surface 910 to fall off. At the same time, the longitudinal ridges 210 and the transverse ridges 220 are staggered to provide support to each other, so that the anti-icing surface structure on the windward surface 910 of the wing can withstand greater wind pressure without being damaged, thereby ensuring that the anti-icing function is stably implemented under high pressure.

[0035] If multiple transverse ridges 220 are arranged in sequence along the windward direction of the wing shell 90, the height of the transverse ridges 220 in the windward section 60 can be gradually reduced. The gradually reduced transverse ridges 220 form an inclined surface, thereby increasing the contact angle between the positive wind pressure and the inclined surface, so that the wind pressure can exert a greater shear force on the ice body on the windward surface 910, making it easier for the ice body on the windward surface 910 to fall off. At the same time, the longitudinal ridges 210 and the transverse ridges 220 are staggered to provide support to each other, so that the anti-icing surface structure on the windward surface 910 of the wing can withstand greater wind pressure without being damaged, thereby ensuring that the anti-icing function is stably implemented under high pressure.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An anti-icing surface structure for aircraft skin, characterized in that: The invention comprises a substrate, a working area is arranged on the substrate, an ice-repelling layer is arranged on the working area, the ice-repelling layer comprises a structural net and an elastic layer arranged on the surface of the structural net, an elastic filling body is arranged in the mesh of the structural net, and the elastic modulus of the structural net is greater than the elastic modulus of the elastic layer and the elastic filling body.

2. The anti-icing surface structure according to claim 1, characterized in that: The elastic layer and the elastic filling body are integrally arranged; And / or, the elastic layer and the elastic filler are respectively low surface energy modified polymer materials.

3. The anti-icing surface structure according to claim 1, characterized in that: A column is arranged in the mesh, the column is located in the middle of the mesh, and the height of the column is less than the depth of the mesh.

4. The anti-icing surface structure according to claim 3, characterized in that: The column is any one of a cylinder, a prism, and a cone, or a combination of at least two of them; And / or, the mesh is any one of a rectangle, a circle, an ellipse, a diamond, a triangle, or a combination of at least two of them.

5. The anti-icing surface structure according to any one of claims 1 to 4, characterized in that: The structural web includes a plurality of longitudinal ridges and a plurality of transverse ridges; Multiple longitudinal ridges are arranged in parallel, the height of the longitudinal ridges is a, the width of the longitudinal ridges is b, the distance between two adjacent longitudinal ridges is c, and the ratio of a, b and c is 2~5:6:16~32; And / or, multiple transverse ridges are arranged in parallel, the height of the transverse ridge is x, the width of the transverse ridge is y, the interval between two adjacent transverse ridges is z, and the ratio of x, y and z is 2~5:6:16~32.

6. The anti-icing surface structure according to claim 5, characterized in that: The height of the longitudinal ridges is 200 μm to 500 μm, and the height of the transverse ridges is 200 μm to 500 μm.

7. The anti-icing surface structure according to claim 6, characterized in that: The structural net is provided with a windward section; A plurality of longitudinal ridges are arranged in sequence along the windward direction, and the height of the longitudinal ridges in the windward section gradually decreases.

8. The anti-icing surface structure according to claim 6, characterized in that: The structural net is provided with a windward section, and a plurality of transverse ridges are arranged in sequence along the windward direction, and the height of the transverse ridges in the windward section gradually decreases.

9. The anti-icing surface structure according to claim 7 or 8, characterized in that: The height gradually decreases from 50μm to 150μm.

10. The anti-icing surface structure according to claim 9, characterized in that: The invention comprises a wing shell, wherein the windward section is arranged on the windward surface of the wing shell.

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