A weather-resistant film for a rear hollowed-out structure of a skin wind power blade and a preparation process thereof

Abstract

The application relates to the technical field of wind power blades, and particularly discloses a weather-resistant coating for a back hollow structure of a wind power blade skin and a preparation process thereof. The weather-resistant coating for the back hollow structure of the wind power blade skin comprises multiple coating units arranged in sections, each coating unit comprises, from inside to outside, an inner bonding film with a thickness of 0.5-1.2 mm, a hollow hollow cavity with a thickness of 2-8 mm and an outer functional film with a thickness of 0.8-1.5 mm; the inner bonding film is used for direct bonding with a blade base body; the hollow hollow cavity is internally provided with support columns and a micro-tube network; the outer functional film is provided with a micro-nano composite hydrophobic structure on the surface, and is distributed with micropores with a pore size of 1-10 microns. The weather-resistant coating has the advantages of high bonding quality, good anti-icing effect, long service life and the like, and can provide strong guarantee for long-term safe and efficient operation of the wind power blade in a harsh environment.

Description

Technical Field

[0001] This application relates to the field of wind turbine blade protection technology, specifically to a weather-resistant coating for the hollowed-out structure of a skin wind turbine blade and its preparation process. Background Technology

[0002] With the rapid development of the global wind energy industry, the single-unit capacity of wind turbines is constantly increasing, and the blade length is also continuously increasing, currently exceeding 100 meters. As the core component of wind turbines for capturing wind energy, the surface condition of the blades directly affects the wind energy conversion efficiency. During service, blades are subjected to multiple environmental stresses such as ultraviolet radiation, temperature changes, wind and sand erosion, rainwater erosion, salt spray corrosion, and icing, making their surfaces highly susceptible to damage, contamination, and icing.

[0003] Currently, wind turbine blade surface protection mainly employs two methods: coating protection and adhesive protective film. Adhesive protective film, due to its advantages such as convenient construction and good protective effect, has gradually become the mainstream solution for protecting the leading edge and overall surface of the blade. However, existing coating technologies still have some shortcomings: First, current coatings are mostly applied as a single section, making it easy for air bubbles to get trapped between the protective film and the blade substrate, reducing the effective bonding area; moreover, stress concentration can easily occur around the bubbles under alternating loads, leading to localized peeling, curling, or even large-area detachment of the film. Second, existing coating materials have limited passive anti-icing effects; the industry mainly relies on shutting down the turbine and waiting for de-icing or manual / mechanical de-icing, which is costly and poses safety hazards.

[0004] Therefore, developing a wind turbine blade coating with high bonding quality, good anti-icing and de-icing effect, and long service life is of great significance for the protection of wind turbine blades. Summary of the Invention

[0005] To overcome the problems of easy icing on the blade surface and insufficient bonding strength and short service life caused by air bubbles during the bonding process in existing wind turbine blade coatings, this application provides a weather-resistant coating for the hollow structure of the skin wind turbine blade, its preparation method and application.

[0006] In a first aspect, this application provides a weather-resistant coating for the hollowed-out structure of a wind turbine blade skin, employing the following technical solution: A weather-resistant coating for the hollow structure behind a wind turbine blade skin includes multiple coating units arranged in segments. Each coating unit includes, from the inside out: an inner adhesive film with a thickness of 0.5-1.2 mm, a hollow cavity with a thickness of 2-8 mm, and an outer functional film with a thickness of 0.8-1.5 mm. The inner adhesive film is used for direct bonding to the blade substrate; The hollow cavity contains support columns and a network of miniature air tubes. The outer functional membrane has a micro-nano composite hydrophobic structure on its surface and is distributed with micropores with a pore size of 1-10 μm.

[0007] This application provides a weather-resistant coating for the hollow structure at the rear of wind turbine blades. Firstly, it replaces the traditional single-section coating with multiple segmented coating units, fundamentally eliminating the problem of insufficient air removal at the interface due to excessively long membrane material during installation. Simultaneously, the segmented structure confines potential localized debonding or damage within individual membrane segments, effectively suppressing large-area peeling and spreading edge curling, significantly improving the overall long-term reliability and service life of the coating under alternating loads and temperature cycles. Secondly, the weather-resistant coating for the hollow structure at the rear of wind turbine blades in this application is a three-layer composite structure consisting of an inner adhesive film, a hollow cavity, and an outer functional film. The hollow cavity contains support columns capable of forming a micro-air network, ensuring the uniformity of thickness and structural stability of the hollow cavity under inflated conditions, allowing the outer functional film to undergo rapid, uniform, and controllable elastic expansion. The outer functional membrane surface features a micro-nano composite hydrophobic structure with micropores. This structure endows the membrane with excellent passive hydrophobic anti-icing capabilities. When not inflated, the surface micropores are closed or semi-closed, ensuring the cleanliness of the cavity and the smoothness of the membrane surface during daily service. During inflation, the micropores open to release gas. Under low-pressure airflow, the gas film formed on the membrane surface prevents liquid water adhesion, thus achieving anti-icing. Under high-pressure pulsed airflow, the rapid elastic expansion of the membrane surface causes the attached ice layer to actively detach due to brittle fracture, achieving simultaneous de-icing and ice removal. Furthermore, the support pillars effectively constrain excessive expansion of the inner and outer membranes, preventing the inner adhesive membrane from peeling off under stress and ensuring that the expansion deformation energy is concentrated on the outer membrane, guaranteeing both de-icing effectiveness and long-term safety of the bonding interface. In summary, the weather-resistant coating for the hollowed-out structure of wind turbine blades provided in this application has the advantages of good adhesion reliability, strong active anti-icing and de-icing capabilities, and excellent structural stability, which can provide strong protection for the long-term safe and efficient operation of wind turbine blades in harsh environments.

[0008] In this application, the length of the coating unit is designed according to the length of the blade protection area. To ensure that air bubbles are completely expelled during the pasting process and to leave a safety margin, the length of a single coating unit is preferably 3-5m.

[0009] Optionally, the pore size of the micropores on the surface of the outer functional membrane is 3-8 μm, and the areal density is 80-150 pores / cm³. 2 .

[0010] In this application, the raw materials for the outer functional film include fluorinated resin, nano-SiO2, modified nano-TiO2, hindered amine light stabilizer, ultraviolet absorber, and microencapsulated flame retardant; the nano-SiO2 has a particle size of 20-50 nm and is added at 2-5 wt% of the matrix resin; the modified nano-TiO2 has a particle size of 80-150 nm and is added at 1-3 wt% of the matrix resin; the hindered amine light stabilizer is added at 0.5-1.5 wt% of the matrix resin; the ultraviolet absorber is added at 0.3-1.0 wt% of the matrix resin; and the microencapsulated flame retardant is added at 3-8 wt% of the matrix resin.

[0011] In this application, the raw materials of the inner adhesive film include the following components in parts by weight: 60-80 parts of bisphenol A type epoxy resin, 20-40 parts of alicyclic epoxy resin, 8-15 parts of toughening agent, 0.5-1.5 parts of coupling agent, and 0.3-1 parts of curing accelerator.

[0012] Optionally, the adjacent coating units are connected by an overlapping or mosaic-style connection structure.

[0013] In this application, the jigsaw puzzle connection structure is selected from biomimetic jigsaw puzzle overlapping or independent jigsaw puzzle connection. Biomimetic jigsaw puzzle overlapping refers to the mating edges of adjacent membrane segments having complementary irregular contours, wherein the irregular contours are wavy curve splicing, sawtooth splicing, or finger-like interlaced splicing; independent jigsaw puzzle connection refers to the edges of each membrane segment having complementary shapes, which interlock in the plane.

[0014] Optionally, the weather-resistant coating for the hollow structure behind the wind turbine blade skin also includes an inflation system; the inflation system has an anti-icing mode, a de-icing mode, and a cooling mode.

[0015] The anti-icing mode of this application is as follows: Under ambient temperatures of -5℃ to 5℃ and humidity ≥80%, a fan is activated to supply air to the hollow cavity of each membrane unit at a pressure of 5-15 kPa, and the gas escapes through the micropores of the outer functional membrane. The de-icing mode involves, when an ice layer is detected on the blade surface, air is injected into the hollow cavity at a pressure of 30-50 kPa and a pressurization rate of 5-10 kPa / s, while optionally activating a heater to deliver hot air at 40-60℃. The cooling mode involves, when the membrane surface temperature exceeds 65℃, introducing ambient temperature airflow for heat dissipation.

[0016] Optionally, the weather-resistant coating for the hollow structure behind the wind turbine blade skin also includes an intelligent sensing and monitoring system.

[0017] Optionally, the inner adhesive film is made of modified epoxy resin base film, the hollow cavity internal support column is made of polycarbonate, and the outer functional film is made of fluorinated resin film.

[0018] Optionally, the diameter of the support column is 1-2 mm, the spacing is 30-50 mm, and the height is 2-8 mm; the water contact angle of the outer functional membrane surface is ≥130°.

[0019] Secondly, this application provides a method for preparing a weather-resistant coating for a hollow structure at the rear of a wind turbine blade, comprising the following steps: preparing an outer functional film, preparing an inner adhesive film, preparing a hollow cavity, and hot-pressing composite. The hot-pressing composite temperature is 130-150℃; the pressure is 0.3-0.8MPa.

[0020] Thirdly, this application provides an application of a weather-resistant coating for the hollow structure of a wind turbine blade in the protection of wind turbine blades, including the following steps: First, clean and polish the surface of the wind turbine blade and apply an epoxy primer; then, paste the coating unit segment by segment onto the surface of the wind turbine blade through an overlapping or mosaic connection structure; the segment pasting is done from the blade root to the blade tip, and after each segment is pasted, use a rubber roller to push and roll it from the center to the periphery 5-8 times to ensure no air bubbles remain; finally, cure at 20-30℃ for 72-90 hours.

[0021] Optionally, each film-covering unit is 2-8m long, with an overlap width of 15-25mm, and the bonding construction time for each film-covering unit is controlled within 15 minutes.

[0022] In summary, this application has the following beneficial effects: 1. This application provides a weather-resistant coating for the hollow structure behind the skin of a wind turbine blade. Through a segmented coating unit design, it fundamentally eliminates the defect of traditional whole-section pasting where the membrane material is too long and cannot completely expel the air at the interface. In addition, the coating of the wind turbine blade is completed by the overlapping / puzzle-like connection structure between adjacent membrane segments. Therefore, local damage is confined to a single membrane segment, which can avoid large-area edge curling and detachment, and significantly improve the long-term service reliability of the coating under alternating loads and temperature cycles.

[0023] 2. The weather-resistant coating of this application has a double-layer hollow perforated structure. With the matching inflation system, combined with the micro-nano composite hydrophobic structure and microporous design on the surface of the outer functional membrane, it can achieve a triple effect of surface hydrophobic anti-icing, microporous air film anti-icing, and inflation expansion de-icing. In addition, the outer functional membrane of the weather-resistant coating is compounded with functional fillers such as fluorinated resin, nano-SiO2, and modified nano-TiO2, and combined with the micro-nano composite structure treated by plasma etching, so that the coating has excellent hydrophobicity, weather resistance, and mechanical properties, which can meet the long-term protection requirements of wind turbine blades in harsh environments such as ultraviolet radiation, wind and sand erosion, and salt spray corrosion. Detailed Implementation

[0024] This application provides a weather-resistant coating for the hollow structure at the rear of a wind turbine blade skin, comprising multiple coating units arranged in segments. Each coating unit, from the inside out, includes: an inner adhesive film with a thickness of 0.5-1.2 mm, a hollow cavity with a thickness of 2-8 mm, and an outer functional film with a thickness of 0.8-1.5 mm. The inner adhesive film is used for direct bonding to the blade substrate. The hollow cavity contains support columns and a network of micro-tubes. The surface of the outer functional film has a micro-nano composite hydrophobic structure and is distributed with pores of 1-10 μm in diameter and an areal density of 50-200 pores / cm². 2 Micropores.

[0025] This application provides a method for preparing a weather-resistant coating for the hollowed-out structure of a wind turbine blade skin, comprising the following steps: (1) Preparation of outer functional film: Using fluorinated resin as the matrix resin, nano-SiO2, modified nano-TiO2, hindered amine light stabilizer, ultraviolet absorber and microencapsulated flame retardant are added, mixed and cast into a film, and then the film surface is subjected to plasma etching treatment to construct a micro-nano composite hydrophobic structure and form micropores to obtain the outer functional film; wherein, the particle size of the nano-SiO2 is 20-50nm, and the amount added is 2-5wt% of the matrix resin; the particle size of the modified nano-TiO2 is 80-150nm, and the amount added is 1-3wt% of the matrix resin; the amount added of the hindered amine light stabilizer is 0.5-1.5wt% of the matrix resin; the amount added of the ultraviolet absorber is 0.3-1.0wt% of the matrix resin; the amount added of the microencapsulated flame retardant is 3-8wt% of the matrix resin; (2) Preparation of inner adhesive film: Bisphenol A type epoxy resin, alicyclic epoxy resin, toughening agent and coupling agent are added to the reaction vessel, heated to 80-90℃, and stirred at 300-500rpm for 20-30min to make the components evenly mixed; then cooled to 50-60℃, added curing accelerator, and continued stirring for 15-20min. After mixing, casting into film and drying, the inner adhesive film is obtained. (3) Preparation of hollow cavity: Polycarbonate support columns are arranged in a diamond array on the upper surface of the inner adhesive film. The diameter of the support columns is 1-2 mm, the spacing is 30-50 mm, and the height is 2-8 mm. The support columns are fixed to the surface of the inner adhesive film by hot pressing. The fixing temperature is 120-140℃, the pressure is 0.1-0.5 MPa, and the pressure holding time is 3-8 s. Then, silicone tubing is arranged in the gaps between the support column array to form a micro air tube network.

[0026] (4) Hot-pressing composite: The outer functional membrane and the inner adhesive membrane with the support column array are hot-pressed to form a double-layer hollow structure; the hot-pressing composite temperature is 130-150℃; the pressure is 0.3-0.8MPa; and the holding time is 45-60s.

[0027] (5) Segmented cutting and structural processing: According to the segmented design of the blade, the composite membrane is cut into multiple standard length segments of the coating unit, and the edges of each coating unit are processed into an overlapping or jigsaw puzzle connection structure.

[0028] This application provides an application of a weather-resistant coating for the perforated structure of a wind turbine blade in the protection of wind turbine blades, comprising the following steps: cleaning and removing contaminants and loose layers of the original coating from the surface of the wind turbine blade; then sanding the blade surface with 240-grit sandpaper and applying an epoxy primer (coating amount of 100-150 g / m²). 2 Next, the membrane units are pasted onto the surface of the wind turbine blade segment by segment using an overlapping or jigsaw puzzle connection method. Each membrane unit is 2-8m long with an overlap width of 15-25mm. The pasting time for each membrane unit is controlled within 15 minutes. The overlapping area is coated with a 0.5mm thick two-component epoxy structural adhesive. The segment pasting proceeds from the blade root to the blade tip. After each segment is pasted, a rubber roller is used to push and roll it from the center to the periphery 5-8 times to ensure no air bubbles remain. Finally, it is cured at 20-30℃ for 72-90 hours.

[0029] The raw materials, reagents, solvents, etc. used in the embodiments of this application are all commercially available.

[0030] The present application will be further described in detail below with reference to embodiments and performance testing. Example 1

[0031] Example 1 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin, the preparation method of which includes the following steps: (1) Preparation of outer functional membrane: (1-1) First, 3g of SiO2 with a particle size of 30nm and 2g of fluorosilane-modified rutile nano-TiO2 with a particle size of 100nm were added to 30g of FEVE fluorocarbon resin (Daikin GK570), and pre-dispersed and ground at 25℃ for 45min using a three-roll mill. Then, the remaining 70g of FEVE fluorocarbon resin, 1g of light stabilizer Tinuvin 292, 0.5g of UV absorber Tinuvin 571 and 5g of microencapsulated flame retardant TF-MF601 were added, and stirred at 700rpm for 30min until uniformly mixed to obtain the outer functional film coating solution; (1-2) The coating liquid is vacuum degassed and introduced into the casting die; the die temperature is controlled at 90℃ and the casting speed is 3m / min; the coating liquid is cast onto a stainless steel strip with a silicone oil-treated surface, and the strip temperature is 70℃. The coating thickness is adjusted by the die opening and the casting speed to achieve a final dry film thickness of 1.0mm. The coated film is then dried and cured in three stages: the first stage at 80℃ for 5min, the second stage at 100℃ for 10min, and the third stage at 120℃ for 5min. After curing, the film is cooled, peeled off, and wound up to obtain a fluoropolymer-based film. (1-3) The above-mentioned fluorinated resin matrix film was placed in a low-temperature plasma treatment device, with argon / oxygen gas at a volume ratio of 4:1 as the working gas. The working gas pressure was adjusted to 40 Pa, the radio frequency power to 200 W, and the treatment time to 90 s. The film surface was bombarded by plasma to form a micron-level uneven structure and a nano-level roughness on the film surface. At the same time, a mask (with a pore size of 6 μm and a pore spacing of 120 pores / cm²) was used. 2 Selective shielding of the plasma distribution allows for the etching of 6 μm diameter pores with a surface density of 120 pores / cm² in the unshielded areas, penetrating the film thickness. 2 The micropores ultimately yielded an outer functional membrane with a thickness of 1 mm.

[0032] (2) Preparation of inner layer adhesive film: 70g of E-44 bisphenol A type epoxy resin, 30g of TDE-85 alicyclic epoxy resin, 10g of carboxyl-terminated liquid nitrile rubber CTBN and 1g of KH560 were added to the reactor and stirred at 90℃ and 400r / min for 30min to make the components evenly mixed; then the temperature was lowered to 55℃, 0.5g of imidazole curing accelerator was added, and stirring was continued for 20min; the mixture was degassed under vacuum and then introduced into the casting die head, the die head temperature was controlled at 55℃ and the casting speed was 3m / min; the coating liquid was cast onto a stainless steel strip with a silicone oil surface to form a film, the strip temperature was 45℃; the film was dried in three stages: the first stage at 60℃ for 5min, the second stage at 80℃ for 10min, and the third stage at 100℃ for 5min, finally obtaining an inner layer adhesive film with a thickness of 0.8mm.

[0033] (3) Preparation of hollow cavity: (3-1) Polycarbonate support columns are arranged in a diamond pattern on the upper surface of the inner adhesive film; the support columns have a diameter of 1.5 mm, a height of 5 mm, and a column spacing of 40 mm; the support columns are fixed to the surface of the inner adhesive film by hot pressing, with a fixing temperature of 130℃, a pressure of 0.3 MPa, and a holding time of 5 s; (3-2) Silicone tubing is laid between the gaps in the support column array to form a micro-air pipe network; one main air pipe (4mm diameter) is laid along the length of the membrane segment, and branch air pipes (2mm diameter) are laid perpendicular to the main air pipe at intervals of 100mm. The ends of each branch air pipe open at the edge of the membrane segment and can be connected to the external inflation system.

[0034] (4) Hot pressing composite: The outer functional membrane is covered on the inner adhesive membrane which is provided with support columns and air pipe network. After aligning the edges, hot pressing composite is performed. The hot pressing temperature is 140℃, the pressure is 0.5MPa, and the holding time is 45s. After hot pressing, a hollow cavity with a thickness of 5mm is formed between the inner and outer membranes to obtain the weather-resistant coating for the hollow structure of the wind turbine blade skin.

[0035] (5) Segmented cutting and structural processing: According to the segmented design of the blade, the composite membrane is cut into multiple standard length segments of the coating unit, and the edges of each coating unit are processed into an overlapping or jigsaw puzzle connection structure. Example 2

[0036] Example 2 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin.

[0037] The difference between the above embodiment and Embodiment 1 is that the micropore size on the surface of the outer functional membrane is 1 μm and the areal density is 200 pores / cm³. 2 Micropores. Example 3

[0038] Example 3 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin.

[0039] The difference between the above embodiment and Embodiment 1 is that the micropore diameter on the surface of the outer functional membrane is 3 μm and the areal density is 150 pores / cm³. 2 Micropores. Example 4

[0040] Example 4 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin.

[0041] The difference between the above embodiment and Embodiment 1 is that the micropore diameter on the surface of the outer functional membrane is 8 μm and the areal density is 80 pores / cm³. 2 Micropores. Example 5

[0042] Example 5 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin.

[0043] The difference between the above embodiment and Embodiment 1 is that the micropore diameter on the surface of the outer functional membrane is 10 μm and the areal density is 50 pores / cm². 2 Micropores. Comparative Example 1

[0044] Comparative Example 1 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin.

[0045] Comparative Example 1 uses the same materials and structure as Example 1, except that the outer functional membrane has a micro-nano composite hydrophobic structure on its surface, but no micropores are provided. Comparative Example 2

[0046] Comparative Example 2 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin.

[0047] Comparative Example 2 uses the same materials and structure as Example 1. The only difference from Example 1 is that the surface of the outer functional film is not subjected to plasma etching and is in a smooth state; however, a microporous structure is provided. Comparative Example 3

[0048] Comparative Example 3 provides a weather-resistant coating unit for the hollowed-out structure of a wind turbine blade skin.

[0049] Comparative Example 3 uses the same materials and structure as Example 1. The only difference from Example 1 is that the membrane is a single-layer solid structure without a hollow cavity and an inflation system. The inner adhesive membrane and the outer functional membrane are directly heat-pressed together, without support columns and air tube network. Performance testing

[0050] Weather-resistant coating test specimens were prepared according to the methods provided in the examples and comparative examples, and their mechanical properties were tested. The results are shown in Table 1 below.

[0051] (1) Surface water contact angle: The water contact angle of the outer functional film of the weather-resistant coating was tested according to GB / T 30693-2014 "Measurement of water contact angle of plastic film". Five measurement points were randomly selected at different positions on the surface of each sample and the average value was taken. The test environment temperature was 23±2℃ and the relative humidity was 50±5%.

[0052] (2) Peel strength: Refer to GB / T 2792-2014 "Test method for peel strength of adhesive tape"; the weather-resistant coating material is pasted onto a glass fiber reinforced epoxy resin composite substrate, cured at 23±2℃ and 50±5%RH for 72h, and the sample is cut into strips 25mm wide. A universal testing machine is used to perform a 180° peel test at a peel rate of 300mm / min, the average peel force during the peeling process is recorded, and the peel strength (the ratio of peel force to width) is calculated. Up to 5 parallel samples are tested in each group, and the average value is taken.

[0053] (3) Anti-icing performance: Refer to the test method for icing delay time in DL / T 1974-2019 "Technical Conditions for Anti-icing Coating Materials for Wind Turbine Blades". Place the coated sample in a low-temperature environmental test chamber with the temperature set at -5±1℃ and the sample at a 45° angle to the horizontal plane. Spray supercooled water mist (water temperature 0-2℃, flow rate 100mL / min, droplet size 10-100μm) onto the sample surface using a spraying device, spray continuously, and record the time from the start of spraying until the ice layer coverage area on the sample surface reaches 5%, which is the icing delay time. Three parallel samples are tested in each group, and the minimum value is taken.

[0054] (4) De-icing performance: Refer to the standard ISO / TS 19392-6 "Coating materials - Coating systems for wind turbine rotor blades - Part 6: Determination and evaluation of ice adhesion using a centrifuge" to test the de-icing performance of weather-resistant coatings. An ice layer of approximately 10 mm thickness was prepared on the surface of the coated sample at -10°C and frozen for 24 h. The outer film was rapidly inflated with 45 kPa pressure, and the ice layer was observed to break and fall off. Ten parallel samples were tested in each group, and the percentage of samples with completely detached ice was recorded as the de-icing success rate.

[0055] Table 1 Performance test results of weather-resistant coatings obtained in Examples 1-5 and Comparative Examples 1-3

[0056] The experimental data in Table 1 show that the water contact angle of the weather-resistant coatings obtained in Examples 1-5 is 132.2-143.7°, the 180° peel strength is 51.8-52.0 N / cm, the icing delay time is 67.8-75.6 min, and the first-time de-icing success rate is 90-100%. Therefore, this demonstrates that the weather-resistant coating provided in this application has excellent surface hydrophobic properties, substrate adhesion strength, and anti-icing and de-icing effects. It can be used in the hollowed-out structure behind wind turbine blades and has good application prospects in cold and extremely harsh environments.

[0057] The de-icing success rate of Comparative Example 1 (without micropores) was only 30%, because the lack of micropore channels prevented the gas filled into the cavity from escaping effectively, and the expansion of the membrane surface alone was insufficient to fully break the ice layer. The de-icing success rate of Comparative Example 2 (without hydrophobic structure) was 70%, which was lower than that of the embodiment but higher than that of Comparative Example 1, indicating that the surface hydrophobicity also has a certain auxiliary effect on the ice layer shedding. The de-icing success rate of Comparative Example 3 (without hollow cavity) was 0%, proving that the de-icing method of inflation expansion adopted in this application can bring significant results.

[0058] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A weather-resistant coating for the hollowed-out structure of a wind turbine blade skin, characterized in that, It includes multiple coating units arranged in segments. Each coating unit includes, from the inside out: an inner adhesive film with a thickness of 0.5-1.2 mm, a hollow cavity with a thickness of 2-8 mm, and an outer functional film with a thickness of 0.8-1.5 mm. The inner adhesive film is used for direct bonding to the blade substrate; The hollow cavity contains support columns and a network of miniature air tubes. The outer functional membrane has a micro-nano composite hydrophobic structure on its surface, and is distributed with pores of 1-10 μm in diameter and an areal density of 50-200 pores / cm². 2 Micropores.

2. The weather-resistant coating for the hollowed-out structure of the wind turbine blade skin according to claim 1, characterized in that, The micropores on the surface of the outer functional membrane have a pore size of 3-8 μm and an areal density of 80-150 pores / cm³. 2 .

3. The weather-resistant coating for the hollowed-out structure of the wind turbine blade skin according to claim 1, characterized in that, The adjacent coating units are connected by an overlapping or jigsaw puzzle structure.

4. The weather-resistant coating for the hollowed-out structure of the skin wind turbine blade according to any one of claims 1-3, characterized in that, The weather-resistant coating for the hollow structure behind the wind turbine blade also includes an inflation system; the inflation system has an anti-icing mode, a de-icing mode, and a cooling mode.

5. The weather-resistant coating for the hollowed-out structure of the wind turbine blade skin as described in claim 4, characterized in that, The weather-resistant coating for the hollowed-out structure behind the wind turbine blade also includes an intelligent sensing and monitoring system.

6. The weather-resistant coating for the hollowed-out structure of the wind turbine blade skin according to claim 1, characterized in that, The inner adhesive film is made of modified epoxy resin, the hollow cavity internal support column is made of polycarbonate, and the outer functional film is made of fluorinated resin.

7. The weather-resistant coating for the hollowed-out structure of the wind turbine blade skin according to claim 1, characterized in that, The diameter of the support columns is 1-2 mm, the spacing is 30-50 mm, and the height is 2-8 mm; the water contact angle of the outer functional membrane surface is ≥130°.

8. The method for preparing the weather-resistant coating for the hollowed-out structure of the wind turbine blade skin as described in any one of claims 1-7, characterized in that, Includes the following steps: Preparation of outer functional membrane, preparation of inner adhesive membrane, preparation of hollow cavity, and hot-pressing composite; The hot-pressing composite temperature is 130-150℃; the pressure is 0.3-0.8MPa.

9. The application of the weather-resistant coating for the hollowed-out structure of the skin wind turbine blade as described in any one of claims 1-7 in the protection of wind turbine blades, characterized in that, Includes the following steps: First, clean and polish the surface of the wind turbine blade and apply an epoxy primer. Then, attach the film-coated units to the surface of the wind turbine blade segment by segment using an overlapping or mosaic connection structure. The segment-by-segment attachment is done from the blade root to the blade tip. After each segment is attached, use a rubber roller to push and roll it from the center outwards 5-8 times to ensure no air bubbles remain. Finally, cure at 20-30℃ for 72-90 hours.

10. The application according to claim 9, characterized in that, Each film-covering unit is 2-8m long and has an overlap width of 15-25mm. The application time for each film-covering unit is controlled within 15 minutes.

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