High-temperature-stealth integrated vortex array sandwich structure based on composite material

Abstract

The invention discloses a high-temperature-stealth integrated vortex array sandwich structure based on a composite material. The high-temperature-stealth integrated vortex array sandwich structure comprises an upper panel; the lower panel and the upper panel are oppositely arranged in parallel; the interlayer structure is arranged between the upper panel and the lower panel, the interlayer structure comprises a plurality of unit structures arranged between the upper panel and the lower panel in an array mode, the two ends of each unit structure are fixedly connected with the upper panel and the lower panel respectively, and each unit structure is of a vortex-shaped structure. According to the gradient design of the multi-stage structure, the impedance matching characteristic of the composite material is remarkably adjusted, the impedance of the structure and the impedance matching degree of a free space are improved, and the absorption loss of electromagnetic waves is enhanced; meanwhile, the arrangement mode of the structure is tight and orderly, multiple reflection and interference paths are provided, and absorption and consumption of electromagnetic waves are enhanced. In addition, the vortex array sandwich structure enables the electromagnetic wave propagation path to be complicated, and the loss of the electromagnetic waves in the propagation process is also increased, so that the purpose of absorbing the electromagnetic waves is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of composite material structure design, and in particular to a high-temperature-stealth integrated vortex array sandwich structure based on composite materials. Background Art

[0002] In recent years, with the rapid development of multi-band and broadband electronic devices, the problem of electromagnetic radiation pollution has become increasingly serious. It is urgent to design efficient electromagnetic wave absorption structures, such as jammers and stealth structures, to reduce or eliminate the harm of electromagnetic waves. The basic principle of using absorbing materials and absorbing structure design to achieve stealth is: the incident wave enters the absorbing medium as much as possible, and then uses the loss of electromagnetic waves to convert electromagnetic waves into heat energy, so that it cannot produce effective echoes, thereby achieving stealth. The sandwich structure is widely used in aerospace and other military equipment due to its excellent properties such as light weight and high temperature resistance.

[0003] The problem of electromagnetic radiation pollution affects the stealth technology of aerospace and can cause great harm to the human body. The technology of reducing or eliminating electromagnetic radiation has become a research hotspot in the social and scientific fields. To solve the above problems, different shapes of absorbing sandwich structures can be set. The traditional absorbing sandwich structure is a two-dimensional honeycomb sandwich structure. The flexibility of the honeycomb sandwich structure is poor and the space utilization rate is low. Compared with the honeycomb sandwich structure, the three-dimensional vortex array sandwich structure has the following advantages: 1) Improve the matching degree of the impedance of the structure with the impedance of free space, and enhance the absorption loss of electromagnetic waves. 2) The arrangement is tight and orderly, with multiple reflection and interference paths, which improves the absorption capacity of electromagnetic waves.

[0004] The core of the high-temperature-stealth integrated vortex array sandwich structure of composite materials is the shape of the sandwich unit structure, so different structural shapes have different effects on the absorption of electromagnetic waves.

[0005] The patent document with application publication number CN112549670A discloses a variable stiffness sandwich composite material structure based on 3D printing and its forming method in the field of composite material design and manufacturing. The variable stiffness sandwich structure design is achieved by changing the wall thickness, distribution uniformity and geometric shape of the core material in the sandwich structure. This invention patent can make appropriate adjustments under different working conditions to achieve lightweight sandwich structures. The preparation method can effectively improve the processing efficiency and quality of complex variable stiffness sandwich structure composite components. However, the sandwich structure is only the most common hexagonal honeycomb sandwich and quadrilateral grid. The sandwich structure is relatively simple, and the impedance of the structure is poorly matched with the impedance of free space, and it is impossible to achieve an ideal wave absorption effect.

[0006] The patent document with application publication number CN118540920A discloses an absorbing structure and absorbing material, wherein the absorbing structure includes a skin layer, a frequency selective layer and a substrate layer, wherein under the condition of oblique incidence of electromagnetic waves, the impedance of the absorbing structure is compensated by the skin layer, and a larger absorption bandwidth can be obtained. The frequency selective layer is a conductive layer with a circular ring-shaped hollow. This invention reasonably designs a multi-layer composite absorbing structure, so that after the electromagnetic wave is incident from the skin layer, multiple interferences occur between the skin layer and the frequency selective layer, and the electromagnetic wave is effectively absorbed and reflected by the frequency selective layer and the substrate layer, thereby achieving the purpose of efficient absorbing. However, the structure of the invention patent is a planar structure, which has poor flexibility and is difficult to adapt to complex engineering needs and design requirements; the space utilization rate is low. In contrast, the three-dimensional structure can be fully utilized in the three-dimensional space, thereby more effectively utilizing the space.

[0007] The patent document with application publication number CN114421181A discloses a wave-absorbing structure. It is made of a base material with electromagnetic loss performance, including: a wave-absorbing plane plate and a plurality of wave-absorbing units, wherein the plurality of wave-absorbing units are spaced apart on the wave-absorbing plane plate and are integrally connected to the wave-absorbing plane plate, and each wave-absorbing unit has a wave-absorbing cavity with an opening at the top. This invention discloses a wave-absorbing structure, which can improve the wave-absorbing capacity without introducing gas or lightweight aggregate into the base. However, the wave-absorbing structure is simple in form, has a small wave-absorbing area, and has a single arrangement of the structure, and cannot perform multiple reflections and interferences, and has poor absorption loss of electromagnetic waves.

[0008] Based on the above technical problems, the present invention provides a high-temperature-stealth integrated vortex array sandwich structure based on composite materials. Summary of the invention

[0009] The purpose of the present invention is to provide a high-temperature-stealth integrated vortex array sandwich structure based on composite materials to solve the problems existing in the prior art.

[0010] To achieve the above object, the present invention provides the following solution: The present invention provides a high temperature-stealth integrated vortex array sandwich structure based on composite materials, comprising:

[0011] Upper panel;

[0012] A lower panel, the lower panel is arranged opposite and parallel to the upper panel;

[0013] A sandwich structure is arranged between the upper panel and the lower panel, and the sandwich structure includes a plurality of unit structures arrayed between the upper panel and the lower panel, and two ends of the unit structure are respectively fixedly connected to the upper panel and the lower panel, and the unit structure is a vortex structure.

[0014] According to the high-temperature-stealth integrated vortex array sandwich structure based on composite materials provided by the present invention, the upper panel material is a glass fiber composite material, the lower panel material is a silicon carbide fiber composite material; the material of the unit structure is aramid fiber / epoxy resin prepreg.

[0015] According to the high-temperature-stealth integrated vortex array sandwich structure based on composite materials provided by the present invention, the top projection contours of the upper panel and the lower panel are both rectangular, and the side length of the upper panel is equal to the side length of the lower panel.

[0016] According to the high-temperature-stealth integrated vortex array sandwich structure based on composite materials provided by the present invention, a plurality of fixed platforms are arrayed on opposite sides of the upper panel and the lower panel, and the fixed platforms on the upper panel are arranged one-to-one with the fixed platforms on the lower panel, and the fixed platforms are of rectangular frame structures, and the two ends of the unit structure are fixedly connected to the fixed platforms on the upper panel and the fixed platforms on the lower panel, respectively.

[0017] According to the high-temperature-stealth integrated vortex array sandwich structure based on composite materials provided by the present invention, the thickness of the fixing platform is 1-2 mm.

[0018] According to the high-temperature-stealth integrated vortex array sandwich structure based on composite materials provided by the present invention, the thickness of the upper panel is 1-2 mm, the thickness of the lower panel is 1-2 mm, the thickness of the unit structure is 20-40 mm, and the total thickness of the upper panel, the lower panel and the unit structure is not more than 44 mm.

[0019] According to the high-temperature-stealth integrated vortex array sandwich structure based on composite materials provided by the present invention, the unit structure is an N-stage vortex unit structure, and the N-stage vortex unit structure includes N-stage vortex rings, and the N-stage vortex rings are connected by transition curves to form a vortex structure.

[0020] According to the high-temperature-stealth integrated vortex array sandwich structure based on composite materials provided by the present invention, the N-stage vortex unit structure is bonded to the fixing platform through an adhesive film, and the adhesive film is a bismaleimide adhesive.

[0021] The present invention discloses the following technical effects:

[0022] The gradient design of the multi-level structure in the present invention significantly adjusts the impedance matching characteristics of the composite material, improves the impedance matching degree of the structure and the impedance of free space, and enhances the absorption loss of electromagnetic waves; at the same time, the arrangement of the structure is tight and orderly, with multiple reflection and interference paths, which enhances the absorption consumption of electromagnetic waves. In addition, the vortex array sandwich structure complicates the propagation path of electromagnetic waves, and the loss of electromagnetic waves in the propagation process also increases accordingly, thereby achieving the purpose of absorbing electromagnetic waves. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments 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.

[0024] Figure 1 This is a schematic diagram of the overall structure of the high-temperature-stealth integrated vortex array sandwich structure designed based on composite materials of the present invention;

[0025] Figure 2 The structure of the embodiment 1 of the present invention is shown in FIG. Figure Ⅰ ;

[0026] Figure 3 The structure of the embodiment 1 of the present invention is shown in FIG. Figure II ;

[0027] Figure 4 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0028] Figure 5 This is a schematic diagram of the structure of Example 3 of the present invention.

[0029] Among them, 1. upper panel; 2. sandwich structure; 3. lower panel; 4. fixed platform; 5. five-stage vortex unit structure; 6. eleven-stage vortex unit structure; 7. six-stage vortex unit structure; 8. first-stage vortex ring; 9. second-stage vortex ring; 10. third-stage vortex ring; 11. fourth-stage vortex ring; 12. fifth-stage vortex ring. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] refer to Figure 1 The present invention provides a high temperature-stealth integrated vortex array sandwich structure based on composite materials, comprising:

[0033] Upper panel 1;

[0034] The lower panel 3 is arranged parallel to the upper panel 1;

[0035] The sandwich structure 2 is arranged between the upper panel 1 and the lower panel 3. The sandwich structure 2 includes a plurality of unit structures arrayed between the upper panel 1 and the lower panel 3. Both ends of the unit structure are fixedly connected to the upper panel 1 and the lower panel 3 respectively. The unit structure is a vortex structure.

[0036] According to a further optimization scheme, the material of the upper panel 1 is a glass fiber composite material, and the material of the lower panel 3 is a silicon carbide fiber composite material; the material of the unit structure is aramid fiber / epoxy resin prepreg.

[0037] According to a further optimization scheme, the top projection contours of the upper panel 1 and the lower panel 3 are both rectangular, and the side length of the upper panel 1 is equal to the side length of the lower panel 3.

[0038] To further optimize the solution, a plurality of fixed platforms 4 are arrayed on opposite sides of the upper panel 1 and the lower panel 3, and the fixed platforms 4 on the upper panel 1 are arranged one by one with the fixed platforms 4 on the lower panel 3. The fixed platforms 4 are rectangular frame structures, and both ends of the unit structure are fixedly connected to the fixed platforms 4 on the upper panel 1 and the fixed platforms 4 on the lower panel 3, respectively.

[0039] According to a further optimized solution, the thickness of the fixing platform 4 is 1-2 mm.

[0040] According to a further optimization scheme, the thickness of the upper panel 1 is 1-2 mm, the thickness of the lower panel 3 is 1-2 mm, the thickness of the unit structure is 20-40 mm, and the total thickness of the upper panel 1, the lower panel 3 and the unit structure is not greater than 44 mm.

[0041] According to a further optimization scheme, the unit structure is an N-stage vortex unit structure, the N-stage vortex unit structure includes N-stage vortex rings, and the N-stage vortex rings are connected by transition curves to form a vortex structure.

[0042] The cross-sectional profile of the N-level vortex ring is rectangular, and the size of the cross-sectional area can be optimized and improved according to the wavelength of the electromagnetic wave. This design helps to reduce weight, while at the same time complicating the electromagnetic wave propagation path and enhancing the absorption loss of the electromagnetic wave.

[0043] Further optimizing the scheme, the N-stage vortex unit structure is bonded to the fixed platform 4 through a film, and the film is a bismaleimide adhesive. Bismaleimide (BMI) adhesive is mostly used in the aerospace field, and can withstand complex stresses such as shearing, peeling, vibration, and impact, and can meet the long life and fatigue performance requirements of the aircraft.

[0044] Embodiment 1:

[0045] refer to Figure 2-3 In this embodiment, N=5, the radius of the first-stage vortex ring 8 of the five-stage vortex unit structure 5 is 24mm, the radius of the second-stage vortex ring 9 is 19mm, the radius of the third-stage vortex ring 10 is 14mm, the radius of the fourth-stage vortex ring 11 is 9mm, and the radius of the fifth-stage vortex ring 12 is 4mm; the thickness of the upper panel 1 is 2mm, the thickness of the sandwich structure 2 is 24mm, the thickness of the lower panel 3 is 2mm, the outer rectangular length of the upper panel 1 fixing platform 4 is 30mm, and the width is 30mm, and the inner rectangular length of the upper panel 1 fixing platform 4 is 28mm, and the width is 28mm; the outer rectangular length of the lower panel 3 fixing platform 4 is 15mm, and the width is 15mm, and the inner rectangular length of the lower panel 3 fixing platform 4 is 13mm, and the width is 13mm; the thickness of the fixing platform 4 is 2mm.

[0046] The upper panel 1 is made of glass fiber composite material. Glass fiber composite material generally has good wave transmission performance and can effectively reduce signal attenuation. The dielectric constant of glass fiber composite material is small, which satisfies the impedance matching between free space and wave absorbing structure. The lower panel 3 is made of silicon carbide fiber composite material. Silicon carbide fiber composite material has good high temperature resistance and can maintain stable physical and chemical properties under high temperature environment. Silicon carbide fiber composite material is light in weight, and silicon carbide fiber composite material can absorb electromagnetic waves in multiple bands and enhance the absorption capacity of electromagnetic waves. The sandwich structure 2 material is made of 3233 resin aramid fiber fabric composite material. Aramid fiber / epoxy resin prepreg has good toughness, excellent flame retardancy and electrical properties. The physical and mechanical properties of aramid fiber and its fabric meet the use requirements of aviation aramid fiber composite materials.

[0047] Example 2

[0048] refer to Figure 4 In this embodiment, N=11, the radius of the first-stage vortex ring 8 of the eleven-stage vortex unit structure 6 is 24mm, the radius of the second-stage vortex ring 9 is 22mm, the radius of the third-stage vortex ring 10 is 20mm, the radius of the fourth-stage vortex ring 11 is 18mm, the radius of the fifth-stage vortex ring 12 is 16mm, the radius of the sixth-stage vortex ring is 14mm, the radius of the seventh-stage vortex ring is 12mm, the radius of the eighth-stage vortex ring is 10mm, the radius of the ninth-stage vortex ring is 8mm, the radius of the tenth-stage vortex ring is 6mm, and the radius of the eleventh-stage vortex ring is 4mm.

[0049] The eleven-level vortex unit structure 6 has a higher structural complexity and contains more concentric circles. This structure can enhance the absorption of electromagnetic waves, which is equivalent to further broadening the wave absorption frequency band. At the same time, this arrangement has a higher pressure bearing capacity, more stable rotation characteristics and stronger wave absorption ability. The unit structure is hollow in the middle, and compared with the convex structure, the convex structure is easily affected by the external environment. This design can make the electromagnetic wave transmission channel more complicated, while also increasing the loss during transmission, thereby achieving the absorption of electromagnetic waves.

[0050] Embodiment 3:

[0051] refer to Figure 5 In this embodiment, N=6, the radius of the first-stage vortex ring 8 of the six-stage vortex unit structure 7 is 24mm, the radius of the second-stage vortex ring 9 is 20mm, the radius of the third-stage vortex ring 10 is 16mm, the radius of the fourth-stage vortex ring 11 is 12mm, the radius of the fifth-stage vortex ring 12 is 8mm, and the radius of the sixth-stage vortex ring is 4mm.

[0052] A vortex array sandwich structure is obtained by a linear array of five-level vortex unit structures 5, eleven-level vortex unit structures 6 and six-level vortex unit structures 7. The five-level vortex, six-level vortex and eleven-level vortex linear array structures have vortex levels that decrease in sequence, with the eleven-level vortex unit in the center, the six-level vortex unit in the inner periphery and the five-level vortex unit in the outer periphery. The unit structures are arranged and distributed in a variable density manner to absorb electromagnetic waves of different wavelengths and enhance the wave absorption capacity. The eleven-level vortex unit structure 6 can more effectively concentrate the energy of the absorbed electromagnetic waves and improve the overall absorption efficiency. The six-level vortex unit structure 7 can play a transitional role and reduce reflection losses. The five-level vortex unit structure 5 can absorb missed electromagnetic waves and enhance the absorption of electromagnetic waves. This arrangement can be adjusted and optimized according to specific application requirements to adapt to different scenarios.

[0053] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0054] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A high temperature-stealth integrated vortex array sandwich structure based on composite materials, characterized in that: include: Upper panel (1); A lower panel (3), the lower panel (3) being arranged opposite and parallel to the upper panel (1); A sandwich structure (2), wherein the sandwich structure (2) is arranged between the upper panel (1) and the lower panel (3), and the sandwich structure (2) comprises a plurality of unit structures arrayed between the upper panel (1) and the lower panel (3), wherein two ends of the unit structure are respectively fixedly connected to the upper panel (1) and the lower panel (3), and the unit structure is a vortex structure.

2. According to claim 1, a high temperature-stealth integrated vortex array sandwich structure based on composite materials is characterized in that: The material of the upper panel (1) is a glass fiber composite material, and the material of the lower panel (3) is a silicon carbide fiber composite material; the material of the unit structure is aramid fiber / epoxy resin prepreg.

3. The high temperature-stealth integrated vortex array sandwich structure based on composite materials according to claim 1, characterized in that: The top-view projection outlines of the upper panel (1) and the lower panel (3) are both rectangular, and the side length of the upper panel (1) is equal to the side length of the lower panel (3).

4. The high temperature-stealth integrated vortex array sandwich structure based on composite materials according to claim 1, characterized in that: A plurality of fixing platforms (4) are arranged in an array on opposite sides of the upper panel (1) and the lower panel (3), and the fixing platforms (4) on the upper panel (1) and the fixing platforms (4) on the lower panel (3) are arranged in a one-to-one correspondence, and the fixing platforms (4) are rectangular frame structures, and the two ends of the unit structure are fixedly connected to the fixing platforms (4) on the upper panel (1) and the fixing platforms (4) on the lower panel (3), respectively.

5. The high temperature-stealth integrated vortex array sandwich structure based on composite materials according to claim 4, characterized in that: The thickness of the fixing platform (4) is 1-2 mm.

6. The high temperature-stealth integrated vortex array sandwich structure based on composite materials according to claim 1, characterized in that: The thickness of the upper panel (1) is 1-2 mm, the thickness of the lower panel (3) is 1-2 mm, the thickness of the unit structure is 20-40 mm, and the total thickness of the upper panel (1), the lower panel (3) and the unit structure is no more than 44 mm.

7. The high temperature-stealth integrated vortex array sandwich structure based on composite materials according to claim 4, characterized in that: The unit structure is an N-stage vortex unit structure, and the N-stage vortex unit structure includes N-stage vortex rings. The N-stage vortex rings are connected by transition curves to form a vortex structure.

8. The high temperature-stealth integrated vortex array sandwich structure based on composite materials according to claim 7, characterized in that: The N-stage vortex unit structure is bonded to the fixing platform (4) via an adhesive film, and the adhesive film is a bismaleimide adhesive.

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