A process for resisting high-speed water impact in the water pressure sensor of a large amphibious aircraft

Abstract

This invention relates to the field of aircraft water load flight testing technology, and specifically to a method for resisting high-speed water impact on water pressure sensors for large amphibious aircraft. This method employs a combination of high-strength aerospace structural adhesive and a water-impact-resistant coating, effectively solving the problem of surface-adhesive water pressure sensors being easily washed away due to surface bonding processes. By adding a certain amount of rigid nanoparticles to the water-impact-resistant coating, the mechanical and adhesive properties of the surface coating itself are greatly improved, effectively protecting the sensor's adhesive seams from the risk of being punctured by high-speed water. This solves the technical problem of water pressure sensors being unsuitable for use on the bottom skin of aircraft, making it possible to conduct large-scale, full-aircraft water load measurements on large amphibious aircraft using surface-adhesive water pressure sensors.

Description

Technical Field

[0001] This invention relates to the field of aircraft water load flight test technology, and to a process method for resisting high-speed water impact on the water pressure sensor of a large amphibious aircraft. Background Technology

[0002] Amphibious aircraft experience complex water loads during takeoff and landing, and the resulting immense impact can cause vibrations in the hull, potentially leading to structural damage. Therefore, developing water load flight testing technology to characterize the effects of these impacts on the hull is crucial. Pressure measurement is the most intuitive method for testing hull load distribution. However, traditional pressure sensors require drilling into the aircraft's hull, which damages the structure and limits their widespread use. Therefore, surface-mounted pressure sensors have emerged as a potential solution for water load flight testing of large amphibious aircraft. Large amphibious aircraft land at approximately 45 m / s, with impact pressures not exceeding 2 MPa. Traditional water-impact resistant coatings withstand water impacts of 20–30 m / s and can only withstand short-term impacts. Therefore, existing impact-resistant methods are unsuitable for the high-speed water impact resistance of surface-mounted water pressure sensors used in large amphibious aircraft. This document clearly describes the magnitude and approximate range of high-speed water impact in this field, along with the magnitude and range of traditional water impact forces. Existing shock-resistant methods are unsuitable for resisting high-speed water impact on surface-mounted water pressure sensors used in large amphibious aircraft. However, surface-mounted pressure sensors face significant challenges during installation. To ensure that the sensor and cables do not damage the aircraft's original structure, riveting, welding, and slotting methods cannot be used to connect and fix the sensor and cables to the aircraft skin. Therefore, adhesive bonding becomes the only option for installing such sensors and cables.

[0003] Based on the actual operating conditions of large amphibious aircraft landing on water, the installation process for sensors and cables needs to address two issues. First, the compressive strength, tensile lap shear strength, and mechanical properties under humid and hot conditions of the adhesive used to bond the sensors and cables must be significantly greater than the actual pressure during water landing. Second, during water landing and high-speed water skidding, the surface coating of the adhesive area for the sensors and cables must simultaneously possess waterproof, high-speed water penetration resistance, abrasion resistance, and seawater corrosion resistance. Therefore, a surface-mount sensor installation method is urgently needed to solve these problems. Summary of the Invention

[0004] Purpose of the invention

[0005] This invention addresses the need for surface-mounted water pressure sensors to measure water loads on large amphibious aircraft, both on land and at sea. It proposes a process for resisting high-speed water impact on surface-mounted water pressure sensors and their cables. This method combines high-strength aerospace structural adhesive with a water-impact resistant coating, effectively solving the problem that surface-mounted water pressure sensors are easily washed away due to the surface bonding process.

[0006] Technical solution

[0007] To address the aforementioned issues, a method for resisting high-speed water impact in the water pressure sensor of a large amphibious aircraft is proposed. This method combines high-strength aerospace structural adhesive with a water-impact resistant coating. By selecting a suitable high-strength aerospace structural adhesive, the sensor can withstand the impact of the aircraft landing on water. Furthermore, by adding a certain amount of rigid nanoparticles to the water-impact resistant coating, the mechanical properties and adhesion of the surface coating itself are improved.

[0008] Includes the following steps:

[0009] Step S100: Use paint remover to remove the topcoat and primer from the designated areas of the aircraft skin.

[0010] Through theoretical simulation, the installation location and number of water pressure sensors are determined based on the magnitude of the water load intensity. Using a clean cloth dampened with acetone, surface contaminants such as grease, oil, and residual dirt are removed from the designated areas of the aircraft skin (water pressure sensors and cables). After the acetone has completely evaporated, tape is used to limit the area requiring paint removal. Then, a brush dampened with paint remover is applied inside the tape-limited area to remove the topcoat and primer from the designated areas of the aircraft skin.

[0011] Step S200: The adhesive-coated patch water pressure sensor is glued to the designated position using an adhesive control device.

[0012] Before bonding, use a clean cloth dampened with acetone to remove surface contaminants from the areas where paint has peeled off, and wait for the acetone to completely evaporate. Use masking tape to define the bonding positions of the patch-type water pressure sensor and cable. The adhesive is specifically a high-strength aerospace structural adhesive. Apply the mixed adhesive evenly to the bonding area of ​​the patch-type water pressure sensor, and then bond the adhesive-coated patch-type water pressure sensor to the designated position on the aircraft skin.

[0013] Step S300: Cover the sensor cable with adhesive.

[0014] After the patch-type water pressure sensor is fixed, quickly use paper tape to fix the cable with the sleeve along the designated position on the aircraft skin. When fixing the cable, it should be tightly attached to the aircraft skin. Then, apply high-strength aerospace structural quick-drying adhesive to the area near the paper tape and apply adhesive to the cable. After the quick-drying adhesive has cured, remove the paper tape and use high-strength aerospace structural adhesive to fully cover the surface of the cable. The thickness and width of the adhesive coverage should be ensured to not affect the hydrodynamics.

[0015] Step S400: Spray resin onto the bonding area: After the adhesive has cured, spray resin onto the bonding seam area of ​​the patch-type water pressure sensor and the area covered by the adhesive cable. First, mix the resin, hardener, and thinner, then apply the resin to the covered area using a brush. After uniform mixing, apply the resin to the covered area using a brush. The curing temperature is room temperature, and the curing time is 12 hours.

[0016] Step S500: Apply a water-impact resistant coating to the bonding area.

[0017] After the resin has cured halfway (after drying at room temperature for 2 hours), spray a water-impact resistant coating onto the adhesive joint areas and the areas covered by the adhesive cables. This is while the resin is still partially cured; spraying the coating in this state effectively increases the adhesion between the surface coating and the underlying resin. First, mix the inorganic particles, resin, hardener, and thinner. Then, apply the resin to the covered areas using a brush. The resin is either a hydrophobic epoxy resin or a hydrophobic polyurethane. For hydrophobic epoxy resins, the hardener is isophorone diamine, diethylenetriamine, etc. For hydrophobic polyurethanes, they need to be mixed according to a two-component ratio.

[0018] Furthermore, Figure 1 The image shows a side view of a glue control device, characterized by a glue control frame 1, a movable base plate 2 placed inside the frame, and four height adjustment screws 3 installed around the back of the frame for adjusting the glue layer thickness. A spring-loaded screw 4 is inserted through the center of the back of the frame and connected to the base plate. During glue application, the spring screw is slightly pressed to separate the sensor from the device.

[0019] Furthermore, during use: place the patch sensor and cable on the movable base plate 2 inside the adhesive control frame 1 according to the shape. Adjust the stroke of the four height adjustment screws 3 to measure the distance between the adhesive surface of the sensor and the surface of the frame 1. The shorter the distance, the less adhesive is applied. Use a scraper to scrape off any excess adhesive along the bottom of the adhesive control device. When adjusting the screw distance, use a vernier caliper to measure the distance between the sensor and the surface of the frame to determine the adhesive layer thickness. Place the adhesive control device with the pressure sensor at the designated position on the bottom skin of the aircraft or ship. Separate the clamp from the sensor by slightly pressing the spring on the back of the clamp and pushing out the screw 4.

[0020] Furthermore, in step S200, during the bonding process, the adhesive control device used here strictly controls the thickness of the adhesive layer between 0.1mm and 0.2mm to reduce the impact of excessive adhesive layer on the hydrodynamic measurement of the sensor on the outer skin surface of the aircraft bottom, and to ensure that the adhesive layer thickness of the patch-type water pressure sensor is uniform and consistent.

[0021] Furthermore, in step S300, the coverage thickness is specifically controlled between 1.2mm and 1.5mm, and the coverage width of the adhesive is controlled between 15mm and 20mm.

[0022] Furthermore, in step S400, the resin is a hydrophobic epoxy resin or a hydrophobic polyurethane. For the hydrophobic epoxy resin, the curing agent is isophorone diamine or diethylenetriamine. For the hydrophobic polyurethane, the components need to be mixed according to a specific ratio. The ratios between the epoxy resin, curing agent, and different components of the polyurethane resin need to be calculated according to the specific formulation.

[0023] Furthermore, in step S500, the inorganic particles are alumina particles and silica particles with a size of 1–100 micrometers, and their addition amount is 30–60 wt.% of the resin. The diluent is ethyl acetate, butyl acetate, ethanol, etc., and its addition amount is 1–2 times the weight of the resin. After uniform mixing, the resin is applied to the coverage area by brushing, and the curing temperature is room temperature, and the curing time is 12 hours.

[0024] Furthermore, for E-51 epoxy resin, the ratio of diethylenetriamine as curing agent is 100:8, and the ratio of isophorone diamine as curing agent is 100:22; the diluent is ethyl acetate, butyl acetate, ethanol, etc., and the amount added is 1 to 2 times the weight of the resin.

[0025] Furthermore, in step S100, the grades of paint remover and adhesive tape are selected based on the materials of the aircraft's topcoat, primer, and skin. Because paint remover is highly corrosive, corrosion-resistant adhesive tape must be used according to process specifications to prevent corrosion of the paint surface in the limiting area. Conventional paper tape can be used during the fixing and bonding of the sensor and optical cable.

[0026] Furthermore, in step S200, the adhesive components are mixed strictly in the specified proportions at the specified temperature according to the adhesive material specifications.

[0027] Furthermore, the selection of adhesive in step S200 depends on the aircraft skin material and the sensor encapsulation material.

[0028] The beneficial effects of this application are as follows:

[0029] This invention solves the technological challenges of existing surface-mounted water pressure sensors, such as the poor mechanical properties of the adhesive that makes them easily detached upon landing on large amphibious aircraft, and the vulnerability of the waterproof coating at the sensor's adhesive seams to high-speed water penetration during landing and high-speed water skidding, thus preventing their application in the aerospace field. Traditional methods of fixing sensors and cables, such as riveting, welding, and grooving, damage the original structure of the aircraft skin and are therefore not permitted for aerospace applications. Therefore, surface bonding becomes the only option. Commonly used fast-drying adhesives for sensors have low mechanical properties and cannot meet the requirements of aircraft landing. By selecting a suitable high-strength aerospace structural adhesive, the sensor can withstand the impact of landing. Furthermore, by adding a certain amount of rigid nanoparticles to the water-resistant coating, the mechanical and adhesive properties of the surface coating itself are greatly improved, effectively protecting the sensor's adhesive seams from high-speed water penetration. This solves the technical problem of water pressure sensors being unusable on the bottom skin of aircraft and makes it possible to use surface-mounted water pressure sensors for large-scale, full-aircraft water load measurement of large amphibious aircraft. Attached Figure Description

[0030] Figure 1 This is a side view of the adhesive control device;

[0031] Wherein: 1-frame, 2-movable base plate, 3-height adjustment screw, 4-spring ejection screw;

[0032] Figure 2 This is a microscopic image of the surface after the coating adhesion test;

[0033] Figure 3 Optical photograph of the coating contact angle test;

[0034] Figure 4 This is an experimental result of the water impact resistant coating.

[0035] Figure 5 The image shows the results of the Taber friction test on the coating. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be described in more detail below. In the examples, the same or similar reference numerals denote the same or similar components or elements having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this invention. The embodiments described below with reference to reference are exemplary and intended to explain this invention, and should not be construed as limiting the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The embodiments of this invention will be described in detail below.

[0037] Typically, 45 measuring points are installed in areas with concentrated water loads to test the aircraft's resistance to water impact. 42 points use analog patches without cables, identical in shape to the water pressure sensor package, while 3 points use water pressure sensors with cables. A clean cloth dampened with acetone is used to remove contaminants such as grease, oil, and residual dirt from the 45 measuring points and the vicinity of the 3 cables on the skin. After the acetone has completely evaporated, masking tape is used to define the areas requiring paint removal. Then, a brush soaked in paint remover is applied inside the tape-defined areas to remove the topcoat and primer from the designated locations on the aircraft skin. The paint remover and tape brands are selected based on the materials of the aircraft's topcoat, primer, and skin.

[0038] Before bonding, use a clean cloth dampened with acetone to remove surface contaminants from areas where paint has peeled off, and allow the acetone to evaporate completely. Use tape to mark the bonding locations of the sensors and cables. Following the supplier's adhesive material specifications, mix the adhesive components strictly according to the specified mixing ratios at the specified temperature. The adhesive used here refers to a high-strength aerospace structural adhesive, the selection of which depends on the aircraft skin material and the sensor encapsulation material. Apply the mixed adhesive evenly to the sensor bonding area, and then bond 42 adhesive-coated analog patches and 3 water pressure sensors with cables to the designated locations on the aircraft skin. During bonding, a specialized adhesive control device is used to strictly control the adhesive layer thickness between 0.1mm and 0.2mm, ensuring a uniform and consistent adhesive layer thickness across all sensors on the aircraft.

[0039] For the three water pressure sensors with cables, after the water pressure sensors are fixed, quickly use masking tape to fix the cables along the designated positions on the aircraft skin. When fixing the cables, they should be tightly attached to the aircraft skin. Then, apply high-strength aerospace structural quick-drying adhesive to the area near the masking tape and apply it to the cables. After the quick-drying adhesive has cured, remove the masking tape and use high-strength aerospace structural adhesive to fully cover the surface of the cables. The thickness of the adhesive coverage should be controlled between 1.2mm and 1.5mm, and the width of the adhesive coverage should be controlled between 15mm and 20mm.

[0040] After the adhesive has cured for 24 hours, resin is sprayed onto the bonding area, sensor joint gaps, and areas covered by the adhesive cable. First, a hydrophobic epoxy resin, isophorone diamine (curing agent), and ethyl acetate (diluent) are mixed. The isophorone diamine content is 25 wt.% of the resin, and the ethyl acetate content is twice the resin content. After uniform mixing, the resin is applied to the covered areas using a brush. The curing temperature is room temperature, and the curing time is 12 hours.

[0041] After the resin has cured to half its original strength (2 hours at room temperature), spray a water-impact resistant coating onto the adhesive joint areas and the areas covered by the adhesive cables. First, mix the hydrophobic epoxy resin with the curing agent isophorone diamine, silica particles, and the diluent ethyl acetate. The isophorone diamine content is 25 wt.% of the resin, and the ethyl acetate content is twice that of the resin. The silica particles have a size of ~5 micrometers and a content of 40 wt.% of the resin. After uniform mixing, apply the resin to the coverage area using a brush. The curing temperature is room temperature, and the curing time is 12 hours.

[0042] The specific number and location of measuring points need to be adjusted according to different water load flight test plans. There are multiple ways to achieve this, and the final implementation result should meet the above sensor installation method and process flow.

[0043] Please add experimental analysis or reports below, consisting of either pure text descriptions or comparative tables recording data. The text and tables should ideally be at least three pages long to fully demonstrate the significant improvement in impact resistance achieved by this method. Comparative black-and-white images are acceptable.

[0044] 1. Selection of structural adhesives

[0045] Considering the actual operating conditions of aircraft water load sea testing, aerospace structural adhesives must possess excellent compressive strength, shear strength, water resistance, and corrosion resistance. Since the aircraft's bottom skin and sensor encapsulation patches are both made of aluminum alloy, adhesives for bonding metal aerospace structures are a potential option. The bonding strength properties of the selected adhesives are shown below:

[0046] 1.1 Tensile lap shear strength

[0047] Tensile lap shear strength at different test temperatures was tested according to ASTM D1002. The bond was made of bare 2024-T3 aluminum material anodized with phosphoric acid according to ASTM D3933. Test data are shown in Table 1.

[0048] Table 1. Tensile lap shear strength at different test temperatures.

[0049] Test temperature (°C) Typical junction (MPa) -55 27.6 25 34.5 82 20.72 107 13.8 121 6.5

[0050] The process variables of the adhesive (different adhesive curing schemes) and the tensile lap shear strength at different test temperatures were tested according to ASTM D1002. The adhesive was 2024-T3AIClad aluminum anodized with phosphoric acid according to ASTM D3933. The test data are shown in Table 2:

[0051] Table 2. Tensile lap shear strength of different curing schemes.

[0052]

[0053] The tensile lap shear strength of the adhesive under conditions of dryness, heat aging, heat / humidity, and aviation fuel was tested according to ASTM D1002. The adhesive was 2024-T3 AIClad aluminum anodized with phosphoric acid according to ASTM D3933 and coated with BR-127 primer. The test data are shown in Table 3.

[0054] Table 3. Tensile lap shear strength under different environments.

[0055]

[0056]

[0057] 1.2 Peel strength

[0058] The peel strength of the floating roller (bell-shaped) was tested according to ASTM D3167. The adhesive was 2024-T3 AIClad aluminum with a 0.020-inch (0.51 mm) peel and a 0.063-inch (1.6 mm) backing skin, phosphate anodized according to ASTM D3933 and coated with BR-127 primer. Test data are shown in Table 4:

[0059] Table 4. Peel strength of floating rollers (bell-shaped).

[0060]

[0061] Peel strength was tested according to ASTM D1876. The adhesive was 0.020 inch (0.51 mm) thick bare aluminum of 2024-T3, anodized with phosphoric acid according to ASTM D3933. Test data are shown in Table 5:

[0062] Table 5. T-Peel peel strength.

[0063]

[0064] 1.3 Compressive strength

[0065] According to ASTM D695, cylindrical samples with a height of 1.42 inches (36 mm) and a diameter of 0.56 inches (14.2 mm) were used. The adhesive was cured at 77°F (25°C) for seven days. Test data are shown in Table 6:

[0066] Table 6. Compressive strength.

[0067]

[0068] Water impact resistant coating and high-speed water impact resistance test

[0069] Considering the actual working conditions of large amphibious aircraft undergoing sea trials with water loads, a waterproof coating needs to be sprayed onto the adhesive surface to prevent seawater corrosion, high-speed water flow penetration, and physical friction. Good adhesion is the primary condition for long-term protection of the coating. This patent first tests the adhesion between the coating and the substrate. According to ASTM D3359, the test results show good adhesion between the coating and the substrate after cross-cutting with a cross-cutting tool, with no peeling. Therefore, its adhesion rating to the substrate is the highest, 5B.

[0070] Then, this patent tests the contact angle of the coating, such as... Figure 3 As shown, the contact angle between the coating and the surface is 156.3°, which is greater than 150°. The surface coating has good hydrophobic properties and reaches a superhydrophobic state.

[0071] Subsequently, this patent tested and compared the water flow impact resistance of two types of densely packed superhydrophobic coatings. In a laboratory environment, two adhesives were selected and bonded to 1mm thick sensor patches at room temperature according to their respective process specifications. After curing, the two coatings were sprayed onto the adhesive joints. Then, a high-pressure water gun (maximum water pressure 15MPa, maximum water velocity approximately 130m / s) was used to continuously irrigate the adhesive joints of the test pieces for 30s, 60s, and 90s, respectively. The water velocity started from 40m / s and increased at 5m / s intervals, stopping at a maximum of 130m / s.

[0072] like Figure 2 As shown, the adhesives without a superhydrophobic coating were all washed away by the high-speed water impact. Adhesive 1 was washed out of the gap, while only a small piece of adhesive 2 was washed away. The patches with water-impact resistant coatings (coating 1 and coating 2) could withstand the impact of high-speed water pressure.

[0073] In addition, the superhydrophobic coating prepared by this patent also has good friction resistance. The wear resistance of the coating was tested by the Taber friction machine and it was found that the coating only lost its superhydrophobic properties after 1000 friction cycles, indicating that the superhydrophobic coating shown by this invention has good durability.

[0074] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein. The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Within the spirit and principles of the present invention, any person skilled in the art may use the disclosed technical content to make changes or modifications to create equivalent embodiments applicable to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention, any modifications, equivalent substitutions, improvements, etc., should be included within the protection scope of the present invention.

Claims

1. A manufacturing method for a water pressure sensor of a large amphibious aircraft to resist high-speed water impact, characterized in that, By combining high-strength aerospace structural adhesive with a water-impact resistant coating, and by selecting a suitable high-strength aerospace structural adhesive, the patch-type water pressure sensor can withstand the impact of the aircraft landing on water. Furthermore, by adding a certain amount of rigid nanoparticles to the water-impact resistant coating, the mechanical properties and adhesion properties of the surface coating itself were improved. Includes the following steps: Step S100: Use paint remover to remove the topcoat and primer from the designated areas of the aircraft skin. Through theoretical simulation, the installation position and number of patch-type water pressure sensors are determined according to the magnitude of water load intensity; use a clean cloth soaked in acetone to remove surface contaminants at the designated location on the skin, and after waiting for the acetone to completely evaporate, use tape to limit the area to be peeled off, and then use a brush soaked in paint remover to apply to the inside of the tape-limited area to remove the topcoat and primer at the designated location on the aircraft skin. Step S200: The adhesive-coated patch water pressure sensor is glued to the designated position using an adhesive control device. Before bonding, use a clean cloth dampened with acetone to remove surface contaminants from the paint-stripped area and wait for the acetone to completely evaporate. Use masking tape to limit the bonding positions of the patch-type water pressure sensor and the cable. The adhesive is a high-strength aerospace structural adhesive. Apply the mixed adhesive evenly to the bonding area of ​​the patch-type water pressure sensor and then bond the adhesive-coated patch-type water pressure sensor to the designated position on the aircraft skin. Step S300: Cover the patch-type water pressure sensor cable with adhesive. After the patch-type water pressure sensor is fixed, quickly use paper tape to fix the cable with the sleeve along the designated position on the aircraft skin. When fixing the cable, it should be tightly attached to the aircraft skin. Then, apply high-strength aerospace structural quick-drying adhesive to the area near the paper tape and apply adhesive to the cable. After the quick-drying adhesive has cured, remove the paper tape and use high-strength aerospace structural adhesive to fully cover the surface of the cable. The thickness and width of the adhesive coverage should be ensured to not affect the hydrodynamics. Step S400: Spray resin on the bonding area: After the adhesive has cured, spray resin on the bonding gap area of ​​the patch-type water pressure sensor and the area covered by the adhesive cable; First, mix the resin with the curing agent and the thinner, and then apply the resin to the covered area by brushing; After uniform mixing, apply the resin to the covered area by brushing, the curing temperature is room temperature, and the curing time is 12 hours. Step S500: Apply a water-impact resistant coating to the bonding area. After the resin has cured halfway, spray an anti-water impact coating on the adhesive seam area of ​​the patch-type water pressure sensor and the area covered by the adhesive cable. This is the state where the resin is not fully cured. Spraying the coating in this state can effectively increase the adhesion between the surface coating and the underlying resin. First, mix the inorganic particles, resin, curing agent, and diluent. Then, apply the resin to the coverage area by brushing. The resin is a hydrophobic epoxy resin or a hydrophobic polyurethane. For hydrophobic epoxy resin, the curing agent is isophorone diamine or diethylenetriamine. For hydrophobic polyurethane, it needs to be mixed according to the two-component ratio.

2. The method as described in claim 1, characterized in that, The adhesive control device includes a frame with a movable base plate inside. Four height-adjustable screws are installed around the back of the frame to adjust the adhesive layer thickness. A spring-loaded screw passes through the center of the back of the frame and connects to the base plate. During bonding, slightly pressing the spring-loaded screw separates the patch-type water pressure sensor from the adhesive control device. In use: Place the patch-type water pressure sensor and cable according to their shape on the movable base plate inside the frame. Adjust the stroke of the four height-adjustable screws to change the distance between the adhesive surface of the patch-type water pressure sensor and the surface of the frame. The shorter the distance, the less adhesive is applied. Excess adhesive is scraped off along the bottom of the adhesive control device with a scraper. When adjusting the distance of the height-adjustable screws, the adhesive layer thickness is determined by measuring the distance between the patch-type water pressure sensor and the surface of the frame with calipers. Place the adhesive control device with the patch-type water pressure sensor in the designated position on the bottom skin of an aircraft or ship. Slightly press the spring-loaded screw on the back of the clamp to separate the clamp from the patch-type water pressure sensor.

3. The method as described in claim 2, characterized in that, In step S200, during the bonding process, the adhesive control device used here strictly controls the thickness of the adhesive layer between 0.1 mm and 0.2 mm to reduce the impact of excessive adhesive layer on the hydrodynamic measurement of the patch-type water pressure sensor on the surface of the aircraft bottom skin, and to ensure that the adhesive layer thickness of the patch-type water pressure sensor is uniform and consistent.

4. The method as described in claim 3, characterized in that, In step S300, the covering thickness is specifically controlled between 1.2 mm and 1.5 mm, and the covering width of the adhesive is controlled between 15 mm and 20 mm.

5. The method as described in claim 4, characterized in that, In step S400, the resin is a hydrophobic epoxy resin or a hydrophobic polyurethane. For hydrophobic epoxy resin, the curing agent is isophorone diamine or diethylenetriamine. For hydrophobic polyurethane, the components need to be mixed in proportion. The proportions between the epoxy resin, curing agent, and different components of the polyurethane resin need to be calculated according to the specific formula.

6. The method as described in claim 5, characterized in that, In step S500, the inorganic particles are alumina particles and silica particles with a size of 1-100 micrometers, and their addition amount is 30-60 wt.% of the resin; the diluents are ethyl acetate, butyl acetate, and ethanol, and their addition amount is 1-2 times the weight of the resin; after uniform mixing, the resin is applied to the covered area by brushing, the curing temperature is room temperature, and the curing time is 12 hours; for E-51 epoxy resin, the ratio is 100:8 when diethylenetriamine is used as the curing agent, and 100:22 when isoflurane diamine is used as the curing agent; the diluents are ethyl acetate, butyl acetate, and ethanol, and their addition amount is 1-2 times the weight of the resin.

7. The method as described in claim 6, characterized in that, In step S100, the grades of paint remover and tape are selected based on the materials of the aircraft's topcoat, primer, and skin. Because paint remover is highly corrosive, corrosion-resistant tape should be used according to the process specifications to avoid corrosion of the paint surface in the limiting area. Conventional paper tape can be used in the fixing and bonding process of the patch-type water pressure sensor and optical cable.

8. The method as described in claim 7, characterized in that, In step S200, the adhesive components are mixed strictly in the specified proportions at the specified temperature according to the adhesive material specifications.

9. The method as described in claim 8, characterized in that, The selection of adhesive in step S200 depends on the aircraft skin material and the encapsulation material of the patch-type water pressure sensor.

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