Tile-shaped wire core cable with self-repairing and uniform temperature heat insulation functions and preparation method thereof
By using high-purity oxygen-free copper to form a tile-shaped main core that is tightly bonded to a circular central zero core, combined with a microcapsule dual dynamic bond self-healing insulation layer, a gradient pore aerogel insulation layer, and a modified cold-resistant PVC outer sheath, the problems of insufficient core bonding, single self-healing mechanism, poor temperature uniformity and insulation synergy, low flame retardant and fire-resistant margin, and single outer sheath function are solved. This achieves a compact cable structure, efficient self-healing, precise temperature uniformity and insulation, high-grade flame retardancy, and wide-temperature-range cold resistance and water repellency, while reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- FAR EAST CABLE
- Filing Date
- 2026-04-03
- Publication Date
- 2026-06-19
Smart Images
Figure CN121964256B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of power cable technology, and in particular to a corrugated core cable with self-healing and uniform temperature insulation functions and its preparation method. Background Technology
[0002] Power cables are core components of power supply systems, and their structure and performance directly affect power supply safety and service life. Existing traditional power cables and conventional corrugated core cables still have many shortcomings in practical applications:
[0003] Insufficient optimization of wire core structure: Conventional corrugated wire cores only achieve the inner arc surface to fit with the neutral wire core, while the outer arc surface is a smooth structure, resulting in insufficient bonding force with the insulation layer. Furthermore, the wire core fitting gap is large and the filling rate is low, requiring more filling material. The cable compactness needs to be improved.
[0004] Limited self-healing ability of insulation: Existing self-healing insulation layers mostly rely on the single external repair mechanism of microcapsules, which has low repair efficiency and few repair cycles. They lack an internal dynamic bond repair system and cannot repair mechanical and electrical damage at the same time. The problems of electrical tree and water tree expansion have not been fundamentally solved.
[0005] Poor uniform temperature insulation performance: Conventional aerogel insulation layers have a uniform porous structure, resulting in poor synergy between insulation and heat conduction. The uniform temperature copper foil lacks insulation protection, making it prone to partial discharge. Furthermore, the bonding stability between aerogel and copper foil is insufficient.
[0006] Flame retardant and fire-resistant performance needs to be upgraded: Conventional metal hydroxide flame retardant materials are single components with low flame retardant efficiency; fire-resistant mica tape has no nano flame retardant doping and low wrapping overlap rate; the flame retardant performance of some cables is only close to the GB31247-2014 Class A threshold and the fire resistance stability is poor.
[0007] The outer protective layer has a single function: conventional modified cold-resistant PVC outer protective layer only achieves cold resistance by adding plasticizers, without the hydrophobic function of the material itself. The surface anti-slip protrusions are smooth, which makes it easy to slip when laid in high humidity environment. In addition, the low temperature embrittlement temperature is relatively high, and the adaptability to a wide temperature range is poor.
[0008] Low precision in manufacturing process: The concentricity deviation of molds in conventional co-extrusion and extrusion processes is large, there is no gradient pore control in aerogel preparation, and anti-slip protrusions and hydrophobic textures cannot be formed synchronously, resulting in insufficient bonding force and poor performance consistency of each layer of the cable.
[0009] Among existing cutting-edge technologies, dynamic covalent self-healing materials have been applied to cable insulation, but they have not been combined with microcapsules to form a dual-repair system; the application of gradient-pore aerogel in the field of thermal insulation has been reported, but it has not been combined with the temperature-equalizing copper foil of power cables; bulk hydrophobic modified PVC has achieved waterproof and antifreeze properties, but it has not been integrated into the outer sheath of the cable and combined with anti-slip protrusions. Therefore, there is an urgent need to develop a new type of corrugated core cable that integrates cutting-edge technologies and comprehensively optimizes structure and performance, achieving a compact structure, efficient self-healing, precise temperature-equalizing insulation, high-grade flame retardancy and fire resistance, and wide-temperature-range cold resistance and hydrophobicity. Summary of the Invention
[0010] The technical problems to be solved by the present invention are: insufficient bonding strength of existing cable cores, single self-repair mechanism, poor temperature uniformity and heat insulation synergy, low flame retardant and fire resistance margin, single function of outer sheath, and low precision of manufacturing process.
[0011] The technical solution adopted by this invention to solve its technical problem is: a tile-shaped core cable with self-healing and uniform temperature insulation functions, the cross-section of which, from the inside to the outside, includes: a core assembly, a self-healing insulation layer, an inner uniform temperature insulation layer, a fire-resistant isolation layer, a flame-retardant filling layer, and a modified cold-resistant outer sheath; the core assembly consists of one circular central neutral core and two to four tile-shaped main cores, the inner arc surface of the tile-shaped main cores is tightly fitted with the outer circumferential surface of the circular central neutral core, and the outer arc surface of the tile-shaped main cores has an arc-shaped concave-convex structure; both the main cores and the neutral cores are made of high-purity oxygen-free copper with a purity ≥99.995% and are compacted. The self-healing insulation layer is a photo-hydraulic-mechanical-thermal quadruple-response self-healing composite material of dual dynamic bond synergistic microcapsules; the inner temperature uniform insulation layer is composed of an inner temperature uniform copper foil and a gradient pore structure aerogel insulation layer; the fire-resistant isolation layer is a high-silica fire-resistant mica tape with a thickness of 0.15-0.25mm; the flame-retardant filling layer is an inorganic flame-retardant material of magnesium hydroxide-aluminum hydroxide composite metal hydroxide with a filling density of 0.9-1.1g / cm³; the modified cold-resistant outer protective layer is a bulk hydrophobic modified cold-resistant PVC material with anti-slip protrusions on the surface, and the protrusion surface has a micro-nano hydrophobic texture.
[0012] The gap between the tile-shaped main wire core and the circular center zero wire core is ≤0.15mm, the wire core filling rate is ≥97%, and the depth of the arc-shaped concave-convex structure on the outer arc surface of the tile-shaped main wire core is 0.3~0.5mm and the width is 0.8~1.2mm.
[0013] The self-healing insulating layer has microcapsule particle size of 8-15 μm, repair agent doping amount of 8-12 wt%, composite DA bond and disulfide bond dual dynamic bond repair system in microcapsules, self-healing insulating layer thickness of 0.6-1.0 mm, and 24h self-healing efficiency ≥98%.
[0014] The thickness of the internal temperature-equalizing copper foil is 0.06-0.09 mm, and the surface is coated with a nano-alumina insulating layer. The pore size of the gradient pore structure aerogel insulation layer increases from 5-10 nm to 20-30 nm from the inside to the outside, and the thermal conductivity of the aerogel is ≤0.025 W / (m·K).
[0015] The high-silica fire-resistant mica tape of the fire-resistant isolation layer has an overlap rate of ≥30%, and the mica tape is doped with 5-8 wt% nano-silica flame-retardant powder.
[0016] The mass ratio of magnesium hydroxide to aluminum hydroxide in the flame-retardant filler layer is 3:1 to 4:1, and the filler layer is doped with 2 to 3 wt% graphene microflakes. The total calorific value (PCS) of the flame-retardant filler layer is ≤1.8 MJ / kg.
[0017] The modified cold-resistant outer protective layer has a service temperature range of -50℃ to 130℃, a low-temperature embrittlement temperature of ≤-50℃, a surface water contact angle of ≥115°, an anti-slip protrusion height of 1.2 to 1.8 mm, an axial spacing of 6 to 7 cm, and a protrusion height of 50 to 100 nm for the micro-nano hydrophobic texture.
[0018] The method for preparing the aforementioned corrugated core cable includes the following steps:
[0019] S1: High-purity oxygen-free copper rods are precisely pressed and formed into a tile-shaped main wire core (12) with an outer arc surface and a circular center zero wire core, which are then assembled into a wire core assembly.
[0020] S2: A self-healing insulating layer of dual dynamic bond synergistic microcapsules is extruded onto the outside of the core module using a double-layer co-extrusion process;
[0021] S3: The inner uniform temperature copper foil coated with nano-alumina is bonded to the arc-shaped groove plate and filled with gradient pore structure aerogel to form an inner uniform temperature insulation layer.
[0022] S4: High-silica refractory mica tape doped with nano-silica is wrapped around to form a refractory isolation layer;
[0023] S5: An inorganic flame-retardant material consisting of a compound metal hydroxide and graphene microsheets is filled between the fire-resistant isolation layer and the outer protective layer to form a flame-retardant filling layer.
[0024] S6: The body is modified by extrusion process to extrude a hydrophobic modified cold-resistant outer layer, and anti-slip protrusions with micro-nano hydrophobic texture are formed simultaneously.
[0025] In S2, the inner extrusion temperature of the self-healing insulation layer is 165-175℃, and the outer extrusion temperature is 170-180℃. The concentricity deviation of the die for the double-layer co-extrusion is ≤0.05mm. In S6, the extrusion temperature of the modified cold-resistant outer sheath is 175-185℃, and the micro-nano hydrophobic texture is formed simultaneously through the die indentation process.
[0026] The gradient pore structure aerogel in S3 was prepared by a stepwise sol-gel method. First, the inner layer of small-particle-size aerogel sol was filled, and then the outer layer of large-particle-size aerogel sol was filled. After supercritical drying, a gradient pore structure was formed. The bonding strength between the aerogel and the arc-shaped groove plate is ≥2.5MPa.
[0027] The beneficial effects of this invention are:
[0028] (1) The arc-shaped concave-convex structure on the outer arc surface of the tile-shaped main wire core of the present invention increases the bonding force with the insulation layer, reduces the bonding gap to ≤0.15mm, increases the filling rate to ≥97%, reduces the amount of filling material by more than 40%, and reduces the outer diameter of the cable by 15% to 20% compared with the traditional structure, making the structure more compact; the purity of the copper material of the wire core is increased to ≥99.995%, the resistivity is further reduced, and the conductivity is better;
[0029] (2) The dual system of dual dynamic bond internal repair + microcapsule external repair, with the addition of a thermal response repair mechanism, achieves quadruple response self-repair, with a 24h self-repair efficiency of ≥98%, and can repair mechanical and electrical damage multiple times, effectively inhibiting the expansion of electrical tree and water tree, and increasing the cable insulation life to more than 3 times that of traditional cables.
[0030] (3) The uniform temperature copper foil is coated with a nano aluminum oxide insulation layer to avoid partial discharge. The gradient pore aerogel achieves the synergy of heat insulation and toughness. The thermal conductivity is ≤0.025W / (m·K), the heat uniformity of the wire core is improved by 25%, the cable can withstand low temperature of -50℃ and high temperature of 130℃, without embrittlement or aging. The uniform temperature insulation is more precise, and the high and low temperature adaptability is stronger.
[0031] (4) The total calorific value of the flame-retardant filler layer of compound metal hydroxide + graphene microsheet is ≤1.8MJ / kg, which is far superior to the GB31247-2014 Class A standard; the high silica mica tape is doped with nano silica, the wrapping overlap rate is ≥30%, the circuit integrity is more stable in the 950℃ / 90min fire resistance test, the flame-retardant fire resistance safety margin is significantly improved, the flame-retardant fire resistance level is improved, and the safety margin is higher.
[0032] (5) The water contact angle of the hydrophobic modified PVC outer sheath is ≥115°, which realizes waterproof, salt spray and corrosion protection, and solves the problem of easy peeling of the surface hydrophobicity; the operating temperature range is widened to -50℃~130℃, and the low temperature embrittlement temperature is ≤-50℃, which is suitable for extreme environments such as freeze-thaw cycles and high humidity salt spray; the anti-slip raised strip has micro-nano hydrophobic texture, which improves the anti-slip performance by 30%, and is suitable for various laying methods such as pipes, cable trays and tunnels. The outer sheath is integrated with cold resistance and hydrophobicity, and has a wider range of environmental adaptability.
[0033] (6) Double-layer co-extrusion, in-mold embossing, step-by-step sol-gel processes achieve precise control of each layer structure, mold concentricity deviation ≤0.05mm, bonding force of each layer ≥2.5MPa, product performance consistency is improved, suitable for large-scale industrial production;
[0034] (7) All materials are low-smoke, low-toxicity and low-corrosion types, which meet environmental protection requirements; the compact structure reduces the amount of materials used, the long service life reduces the cost of maintenance and replacement, and the overall cost of use is more than 25% lower than that of traditional cables. Attached Figure Description
[0035] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0036] Figure 1 This is a schematic diagram of the cross-sectional structure of the cable of the present invention.
[0037] Figure 2 This is a schematic diagram of the internal structure of the tile-shaped main wire core of the present invention.
[0038] Figure 3 This is a schematic diagram of the surface structure of the modified cold-resistant outer protective layer of the present invention.
[0039] In the figure: 1. Core assembly, 11. Circular central zero core, 12. Tile-shaped main core, 2. Self-healing insulation layer, 3. Inner uniform temperature insulation layer, 31. Inner uniform temperature copper foil, 32. Gradient pore structure aerogel insulation layer, 4. Fire-resistant isolation layer, 5. Flame-retardant filling layer, 6. Modified cold-resistant outer protective layer, 61. Anti-slip protrusions, 62. Micro-nano hydrophobic texture. Detailed Implementation
[0040] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.
[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0042] Figure 1 , Figure 2 and Figure 3The self-healing and temperature-uniform insulation corrugated core cable shown is suitable for low-voltage power supply systems in nuclear power plants. It includes: core assembly 1, self-healing insulation layer 2, inner temperature-uniform insulation layer 3, fire-resistant insulation layer 4, flame-retardant filling layer 5, and modified cold-resistant outer sheath 6. The specific structure and parameters are as follows:
[0043] Core assembly 1: 3 corrugated main cores 12 (70mm) 2 ), 1 round center neutral wire core 11 (35mm) 2 The copper material has a purity of 99.996%. The outer arc surface of the tile-shaped main wire core 12 has a depth of 0.4mm and a width of 1.0mm. The gap between it and the circular center zero wire core 11 is 0.12mm. The wire core filling rate is 98%.
[0044] Self-healing insulating layer 2: 0.8 mm thick, microcapsule particle size 10-12 μm, repair agent doping amount 10 wt%, composite DA bond and disulfide bond dual dynamic bond repair system, 99% self-healing efficiency in 24 h.
[0045] Inner uniform temperature insulation layer 3: Inner uniform temperature copper foil 31 with a thickness of 0.08 mm, with a 50 nm nano aluminum oxide insulating layer plated on the surface; gradient pore structure aerogel insulation layer 32 with an inner pore diameter of 6-8 nm and an outer pore diameter of 22-25 nm; aerogel thermal conductivity of 0.022 W / (m·K); and aerogel bonding strength to arc-shaped groove plate of 3.0 MPa.
[0046] Fire-resistant isolation layer 4: High-silica fire-resistant mica tape with a thickness of 0.2mm, doped with 6wt% nano-silica flame-retardant powder, with a wrapping overlap rate of 35%.
[0047] Flame-retardant filler layer 5: Magnesium hydroxide to aluminum hydroxide mass ratio 3.5:1, doped with 2.5wt% graphene microflakes, filling density 1.0 g / cm³ 3 The total calorific value (PCS) is 1.6 MJ / kg.
[0048] Modified cold-resistant outer protective layer 6: The body is hydrophobic modified cold-resistant PVC, with a service temperature range of -50℃~130℃, a low temperature embrittlement temperature of -52℃, a surface water contact angle of 118°, anti-slip protrusions 61 with a height of 1.5mm and an axial spacing of 6.5cm, and micro-nano hydrophobic textures 62 with a protrusion height of 80nm.
[0049] The preparation method of this embodiment includes the following steps:
[0050] The 99.996% high-purity oxygen-free copper rod is formed by a precision compression molding machine to produce a tile-shaped main wire core 12 with an outer arc surface and a circular center zero wire core 11. The wire core assembly 1 is then manually assembled to ensure that the fitting gap is ≤0.15mm.
[0051] A self-healing insulating layer 2 is extruded onto the outside of the core component 1 using a double-layer co-extrusion machine. The inner layer extrusion temperature is 170℃, the outer layer extrusion temperature is 175℃, the die concentricity deviation is 0.04mm, and the extrusion is water-cooled for shaping.
[0052] The inner uniform temperature insulation layer 31 is prepared by wrapping an inner uniform temperature copper foil 31 coated with nano-alumina using a wrapping machine, bonding an arc-shaped glass fiber channel plate, first filling the inner layer with small-particle-size aerogel sol using a stepwise sol-gel method, and then filling the outer layer with large-particle-size aerogel sol. After supercritical CO2 drying, a gradient pore structure aerogel insulation layer 32 is formed, thus completing the preparation of the inner uniform temperature insulation layer 3.
[0053] A high-silica fire-resistant mica tape doped with nano-silica was wrapped using a wrapping machine, with the wrapping overlap rate controlled at 35%, to form a fire-resistant isolation layer 4.
[0054] An inorganic flame-retardant material, composed of magnesium hydroxide-aluminum hydroxide composite and doped with graphene microflakes, is filled on the outside of the refractory isolation layer 4. A vacuum filling process is used to ensure a filling density of 1.0 g / cm³. 3 , forming a flame-retardant filler layer 5.
[0055] The hydrophobic modified cold-resistant PVC material is extruded using a bulk modified extruder at an extrusion temperature of 180℃. Anti-slip protrusions 61 with micro-nano hydrophobic texture 62 are simultaneously formed through a mold with an embossed structure to form a modified cold-resistant outer protective layer 6. After air cooling and shaping, it is wound up.
[0056] The performance specifications of the cable in this embodiment are as follows:
[0057] Structural specifications: The cable outer diameter is reduced by 18% compared to the traditional 3+1 structure cable, and the amount of filler material used is reduced by 42%;
[0058] Self-healing performance: 99% self-healing efficiency in 24 hours, and 98% breakdown strength recovery rate after electrical tree damage repair;
[0059] Uniform temperature insulation performance: The uniformity of the working temperature rise of the wire core is improved by 28%, and the thermal conductivity of the aerogel insulation layer is 0.022W / (m·K);
[0060] Flame retardant and fire resistance performance: Total calorific value PCS 1.6MJ / kg, meeting GB31247-2014 Class A flame retardant requirements; the electrical integrity of the circuit is good in the 950℃ / 90min fire resistance test.
[0061] Outer protective layer performance: low-temperature embrittlement temperature -52℃, surface water contact angle 118°, anti-slip raised friction coefficient increased by 35%;
[0062] Electrical conductivity: Core resistivity 0.0170 Ω·mm 2 / m (20℃), which is better than the requirements of the national standard GB / T3956-2008.
[0063] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.
Claims
1. A tile-shaped wire core cable having self-repairing and uniform temperature insulation functions, characterized in that, The cross-section, from the inside out, includes: a wire core assembly (1), a self-healing insulation layer (2), an inner temperature-regulating insulation layer (3), a fire-resistant isolation layer (4), a flame-retardant filling layer (5), and a modified cold-resistant outer protective layer (6); the wire core assembly (1) consists of one circular central neutral wire core (11) and two to four tile-shaped main wire cores (12), the inner arc surface of the tile-shaped main wire core (12) is tightly fitted with the outer circumference of the circular central neutral wire core (11), and the outer arc surface of the tile-shaped main wire core (12) has an arc-shaped concave-convex structure; both the main wire core and the neutral wire core are made of high-purity oxygen-free copper with a purity ≥99.995% and are compacted; the self-healing insulation layer (2) is a dual-dynamic The composite material of photo-hydraulic-mechanical-thermal quadruple response of the bond-synergistic microcapsule; the inner temperature uniform insulation layer (3) is composed of an inner temperature uniform copper foil (31) and a gradient pore structure aerogel insulation layer (32); the fire-resistant isolation layer (4) is a high silica-oxygen fire-resistant mica tape with a thickness of 0.15-0.25mm; the flame-retardant filling layer (5) is an inorganic flame-retardant material of magnesium hydroxide-aluminum hydroxide composite metal hydroxide with a filling density of 0.9-1.1g / cm³; the modified cold-resistant outer protective layer (6) is a bulk hydrophobic modified cold-resistant PVC material with anti-slip protrusions (61) on the surface, and the protrusion surface is a micro-nano hydrophobic texture (62).
2. The flat cable according to claim 1, wherein The gap between the tile-shaped main wire core (12) and the circular center zero wire core (11) is ≤0.15mm, the wire core filling rate is ≥97%, and the depth of the arc-shaped concave-convex structure on the outer arc surface of the tile-shaped main wire core (12) is 0.3~0.5mm and the width is 0.8~1.2mm.
3. The flat cable according to claim 1, wherein The microcapsules in the self-healing insulating layer (2) have a particle size of 8-15 μm and a doping amount of 8-12 wt% for the repair agent. The microcapsules contain a dual dynamic bond repair system of composite DA bonds and disulfide bonds. The thickness of the self-healing insulating layer (2) is 0.6-1.0 mm, and the self-healing efficiency is ≥98% after 24 hours.
4. The flat cable according to claim 1, wherein The thickness of the internal temperature uniform copper foil (31) is 0.06-0.09 mm, and the surface is coated with a nano-alumina insulating layer. The pore size of the gradient pore structure aerogel insulation layer (32) increases from 5-10 nm to 20-30 nm from the inside to the outside. The thermal conductivity of the aerogel is ≤0.025 W / (m·K).
5. The flat cable according to claim 1, wherein The fire-resistant isolation layer (4) has a high silica-oxygen fire-resistant mica tape wrapping overlap rate of ≥30%, and the mica tape is doped with 5-8 wt% nano-silica flame-retardant powder.
6. The flat cable according to claim 1, wherein The mass ratio of magnesium hydroxide to aluminum hydroxide in the flame-retardant filler layer (5) is 3:1 to 4:1, and the filler layer is doped with 2 to 3 wt% graphene microplates. The total calorific value of the flame-retardant filler layer (5) is ≤1.8 MJ / kg.
7. The flat cable according to claim 1, wherein The modified cold-resistant outer protective layer (6) has a service temperature range of -50℃ to 130℃, a low-temperature embrittlement temperature of ≤-50℃, a surface water contact angle of ≥115°, an anti-slip protrusion (61) height of 1.2 to 1.8 mm, an axial spacing of 6 to 7 cm, and a protrusion height of 50 to 100 nm for the micro-nano hydrophobic texture (62).
8. The method of producing a flat cable according to any one of claims 1 to 7, characterized in that, Includes the following steps: S1: High-purity oxygen-free copper rods are precisely pressed and formed into a tile-shaped main wire core (12) with an outer arc surface and a circular center zero wire core (11), which are then assembled into a wire core assembly (1). S2: A self-healing insulating layer (2) of dual dynamic bond synergistic microcapsules is extruded on the outside of the core component (1) using a double-layer co-extrusion process; S3: The inner temperature uniform copper foil (31) coated with nano-alumina is wrapped around the inner temperature uniform copper foil (31), and the arc-shaped groove plate is bonded and filled with gradient pore structure aerogel to form an inner temperature uniform insulation layer (3). S4: Wrap high-silica refractory mica tape doped with nano-silica to form a refractory isolation layer (4); S5: Fill the space between the fire-resistant isolation layer (4) and the outer protective layer with an inorganic flame-retardant material containing a compound metal hydroxide and graphene micro flakes to form a flame-retardant filling layer (5); S6: The body is modified by extrusion process to extrude a hydrophobic modified cold-resistant outer protective layer (6), and anti-slip protrusions (61) with micro-nano hydrophobic texture (62) are formed simultaneously.
9. The production method according to claim 8, characterized by, The inner extrusion temperature of the self-healing insulation layer (2) in S2 is 165-175℃, the outer extrusion temperature is 170-180℃, and the concentricity deviation of the mold for double-layer co-extrusion is ≤0.05mm; the extrusion temperature of the modified cold-resistant outer protective layer (6) in S6 is 175-185℃, and the micro-nano hydrophobic texture (62) is formed simultaneously through the in-mold embossing process.
10. The preparation method according to claim 8, characterized in that, The gradient pore structure aerogel in S3 was prepared by a stepwise sol-gel method. First, the inner layer of small-particle-size aerogel sol was filled, and then the outer layer of large-particle-size aerogel sol was filled. After supercritical drying, a gradient pore structure was formed. The bonding strength between the aerogel and the arc-shaped groove plate is ≥2.5MPa.