Large-scale anti-icing / deicing method based on local interface weakening

Abstract

The invention belongs to the technical field of surface ice prevention / removal, and particularly relates to a large-scale ice prevention / removal method based on local interface weakening, which comprises the following steps: applying local stimulation to a coating of which the surface is coated with an ice layer so as to induce local interface weakening, and then applying deicing thrust to the edge of the ice layer so as to remove ice; wherein the local stimulation comprises local pressure fluid stimulation, local ultrasonic stimulation, local electrical stimulation, local mechanical stimulation and local light stimulation; a local stimulus is applied toward the interface between the ice layer and the coating, and the application location is proximate to the application location of the deicing thrust. Compared with the prior art, the problems of poor ice prevention / removal effect, high energy consumption and limited application generally existing in the ice prevention / removal technology in the prior art are solved. According to the method for promoting interface fracture expansion based on local interface weakening, the interface adhesion strength between the ice layer and the coating is reduced by 3-4 times, and low-energy-consumption large-scale ice prevention / removal is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of surface anti-icing / de-icing, and in particular relates to a large-scale anti-icing / de-icing method based on local interface weakening. Background Art

[0002] Extreme conditions such as low temperatures, high humidity, and high wind speeds can easily cause ice to form on the surfaces of ships, aircraft, rail transit, wind turbine blades, and power transmission lines, severely impacting their normal operation and posing significant safety risks. For example, when ships navigate polar regions, seawater splashing onto the cold hull or deck can freeze and form ice, threatening navigation safety. When aircraft operate in extreme environments, ice on wings and tail fins increases surface roughness and flight resistance, altering aerodynamic performance and, in severe cases, causing aircraft instability and crashes. Icing on wind turbine blades can lead to power loss, mechanical failure, and ice throwoff, posing serious safety hazards during wind turbine operation. Ice accumulation on the surfaces of long-distance transmission lines, towers, insulators, and other power transmission infrastructure can overload mechanical components, causing flashover tripping and line disconnection, increasing transmission losses and widespread power outages. Therefore, efficient icing protection technology has important economic value and social benefits in daily life, industrial production, national defense and military industry, etc. It is a difficult problem that needs to be solved urgently in the field of practical engineering applications and material surface and interface science. It is also a core key technology that urgently needs to be broken through in major national scientific and technological strategic layouts such as domestic large aircraft and Arctic routes.

[0003] The existing mainstream anti-icing / deicing technologies mainly include active anti-icing / deicing technologies and passive anti-icing / deicing technologies. Passive anti-icing / deicing strategies mainly use the intrinsic properties of materials to delay, reduce or even prevent ice formation, mainly including liquid anti-icing / deicing technology, antifreeze proteins, photothermal coatings, superhydrophobic surfaces, superslippery surfaces and low interface toughness materials. Liquid anti-icing / deicing technology introduces anti-icing liquid (ethylene glycol, isopropyl alcohol, ethanol, etc.) on the surface of the material to make the anti-icing surface temperature higher than the freezing point and thus inhibit surface ice formation. This technology requires a large amount of organic solvents, which is expensive and easy to cause environmental pollution. Antifreeze proteins in natural organisms can effectively inhibit the formation and growth of ice. Applying the extracted biomass to the surface of the material can improve its anti-icing performance, but its cost is relatively high. Photothermal deicing coatings melt ice and snow by absorbing solar energy and converting it into heat energy. It does not require the use of chemical deicing agents, is environmentally friendly and low-cost, but existing photothermal deicing coatings are limited by the low photothermal conversion efficiency of photothermal materials, and have low deicing efficiency. Superhydrophobic surfaces based on the "lotus effect" exhibit multifunctional properties such as oil-water separation, corrosion resistance, antibacterial, marine antifouling, underwater drag reduction, and self-cleaning due to their low surface energy properties. They can effectively reduce the adhesion of water droplets, delay ice crystal nucleation, prolong the time to complete freezing, and significantly reduce the adhesion between ice and the substrate. However, in extremely low temperature and humid environments, the microstructure of the superhydrophobic coating surface forms an interlocking structure with ice, increasing the ice adhesion strength. To date, there has been no major breakthrough in the mechanical impact resistance of the surface micro-nanostructure of superhydrophobic coatings. Liquid super-slippery surfaces (SLIPS) based on the "pitcher plant" structure have extremely strong liquid repellency and self-healing capabilities, and can maintain good anti- / de-icing performance under various extreme environmental conditions (extreme temperature and humidity changes). However, most super-slippery coating surfaces are usually relatively simple two-dimensional (2D) microstructures, with low ability to store and protect lubricating oil. Factors such as evaporation and wind / jet impact can easily cause continuous loss of lubricating oil. The poor mechanical durability of the microstructure is a key technical bottleneck restricting the engineering application of super-slippery surfaces for anti- / de-icing. For example, the preparation and application of porous PDMS-infiltrated organic oil gel anti-icing / de-icing materials disclosed in CN115353741B achieves lower ice adhesion strength by improving the structure of the coating material so that it can avoid the loss of lubricating fluid. However, this solution still utilizes the effect of the lubricating fluid, and the performance will also change accordingly after changing the structure of the coating material. Therefore, this solution has certain restrictions and requirements on the application objects and application environment, resulting in limited application of this coating. In summary, both super-hydrophobic and super-slippery surfaces require the manufacture of fine micro-nano structures. Existing preparation technologies mostly rely on expensive micro-nano processing equipment and cumbersome chemical synthesis methods, which are inefficient and difficult to meet large-scale and large-scale preparation requirements. In addition, most surface microstructures are prepared based on rigid hard materials, and rigid microstructures are more difficult to resist environmental factors such as mechanical impact.

[0004] Compared to existing passive anti-icing / de-icing methods, active anti-icing / de-icing methods require neither micro- or nanostructured coatings (which have poor mechanical durability and can form interlocking structures in low-temperature, high-humidity environments, increasing ice adhesion) nor surface chemical modification (which has a short anti-icing effect and can easily cause environmental pollution). Active anti-icing / de-icing technologies primarily include chemical de-icing, electrothermal de-icing, mechanical de-icing, and gas-thermal de-icing. Traditional chemical de-icing methods use chemicals such as sodium chloride to lower the freezing point, melting accumulated snow / ice and thereby removing and preventing ice formation. However, this de-icing / de-icing technology is inefficient, and the excessive use of sodium chloride can cause corrosion to metal equipment. Electric heating de-icing methods install a resistance wire on the bottom of components, controlling the surface temperature through the electrothermal effect to prevent and melt ice. However, these methods are complex, energy-intensive, and prone to secondary icing. Manual mechanical de-icing primarily involves breaking up the ice with sharp tools, which is inefficient and can damage equipment. Gas-heat anti-icing technology uses high-temperature, high-pressure steam or water flow to melt ice, which can easily cause high-temperature impact damage to materials and has high energy consumption costs.

[0005] In summary, for large-scale (ice length > 20 cm) deicing, the existing active deicing methods have the problems of high energy consumption, easy secondary icing, and complex deicing system. Summary of the Invention

[0006] The present invention aims to address at least one of the aforementioned issues by providing a large-scale de-icing method based on localized interface weakening. This approach addresses the poor effectiveness, high energy consumption, and limited applicability of existing de-icing technologies. This approach, based on localized interface weakening to promote interfacial fracture propagation, reduces the interfacial adhesion strength between the ice layer and the coating by 3-4 times, achieving low-energy, large-scale de-icing.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] A large-scale anti-icing / de-icing method based on local interface weakening comprises the following steps:

[0009] Applying local stimulation to the coating with ice layer on the surface to induce local interface weakening and promote interface fracture propagation between the ice layer and the coating, and then applying deicing thrust at the edge of the ice layer to de-ice;

[0010] in,

[0011] The local stimulation includes local pressure fluid stimulation, local ultrasound stimulation, local electrical stimulation, local mechanical stimulation and local light stimulation;

[0012] The local stimulation is applied toward the interface between the ice layer and the coating, and the application position of the local stimulation is close to the application position of the deicing thrust.

[0013] Preferably, the local stimulation is local negative pressure air stimulation and / or local ultrasonic stimulation.

[0014] Preferably, the local negative pressure air stimulation is applied by constructing a local flow channel inside the coating and connecting the local flow channel to a negative pressure air pump;

[0015] The pressure applied by the negative pressure air pump is in the range of -10kPa to -5MPa.

[0016] Preferably, the local ultrasonic stimulation is applied by an ultrasonic element attached to the surface of the coating;

[0017] The ultrasonic power applied by the ultrasonic element is in the range of 5W to 200W, and the operating frequency is in the range of 5kHz to 200kHz.

[0018] Preferably, the application position of the local stimulation is located within the range of 0-40 mm of the application position of the deicing thrust, wherein when the application position of the local stimulation is located at 0 mm of the application position of the deicing thrust, the application position of the local stimulation is located at the edge of the ice layer where the deicing thrust is applied.

[0019] Preferably, the application area of ​​the local stimulation is less than 20% of the interface area between the ice layer and the coating.

[0020] Preferably, the adhesion strength between the ice layer and the coating does not exceed 500 kPa.

[0021] Preferably, the coating is a silicone rubber composite material coating plasticized with silicone oil, the elastic modulus of the coating ranges from 50 kPa to 500 kPa, and the adhesion strength between the coatings is less than 100 kPa.

[0022] Preferably, the silicone oil plasticized silicone rubber composite material coating is prepared by the following steps:

[0023] Part A and Part B of Ecoflex 00-30 were stirred and mixed, followed by a first degassing treatment to obtain an Ecoflex precursor solution;

[0024] Silicone oil is added to the Ecoflex precursor solution, followed by stirring and mixing, and then a second degassing treatment is performed to obtain a silicone oil plasticized Ecoflex coating.

[0025] Preferably, one or more of the following are included:

[0026] i) Mix Part A and Part B of Ecoflex 00-30 in a mass ratio of 1:1;

[0027] ii) the first degassing treatment is a vacuum degassing treatment, with stirring at a speed of 1000 rpm for 60 seconds;

[0028] iii) mixing Ecoflex precursor solution and silicone oil in a mass ratio of 1:1;

[0029] iv) the second degassing treatment is a vacuum degassing treatment, with stirring at a speed of 2000 rpm for 5 minutes;

[0030] v) The viscosity of the silicone oil is 1000 cst.

[0031] The working principle of the present invention is:

[0032] Local stress stimulation is applied at or near the edge of the loading end (the end where deicing thrust is applied) of the interface between the ice layer and the coating to induce local interface weakening, promote the fracture extension of the interface between the ice layer and the coating, and reduce the adhesion strength of the interface between the ice layer and the coating.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. The present invention introduces local stress stimulation at the loading end (the end where deicing thrust is applied) of the interface between the ice layer and the coating, thereby inducing local interface weakening and promoting fracture expansion at the interface between the ice layer and the coating.

[0035] 2. The present invention introduces local stimulation interface weakening, which reduces the adhesion strength of the interface between the ice layer and the coating by 3-4 times, achieving large-scale anti-icing / de-icing with low energy consumption.

[0036] 3. The present invention establishes a finite element model of local stimulation of interface weakening to promote interface fracture extension, revealing the mechanical mechanism of local stimulation-induced fracture extension at the ice-coating interface.

[0037] 4. The effective area of ​​the local stimulation applied in the present invention is less than 20% of the interface area between the ice layer and the coating, which is significantly smaller than the effective area required by existing anti-icing / de-icing technologies, and can reduce the overall anti-icing / de-icing energy consumption.

[0038] 5. The present invention designs an anti-icing coating made of silicone oil-plasticized silicone rubber composite material with a low elastic modulus. The elastic modulus of the coating ranges from 50kPa to 500kPa. The low elastic modulus property ensures that the ice adhesion strength of the coating is less than 100kPa, thereby ensuring that a large-area active deicing effect can be achieved by applying local stimulation.

[0039] 6. The location where the local stimulation of the present invention is applied must be at the starting point of the force-bearing end of the interface between ice and coating, which can have a good stress concentration effect, thereby reducing the de-icing force required to be applied.

[0040] 7. The present invention proves that the closer the local stimulation application position is to the starting position of the force-bearing end, the smaller the de-icing force is, and the farther the local stimulation application position is from the starting position of the force-bearing end, the greater the de-icing force is.

[0041] 8. The present invention verifies the effectiveness of the large-scale anti-icing / de-icing method of locally stimulating interface weakening and promoting interface fracture extension by designing a large-scale anti-icing / de-icing experiment in which local negative pressure air stimulation and local ultrasonic stimulation are used to induce local interface weakening and promote interface fracture extension.

[0042] 9. This invention is a low-cost, highly effective active deicing method. In addition to its advantages over existing passive deicing methods, it is also a purely physical deicing method, theoretically providing indefinite, high-efficiency deicing capabilities. This method uses localized stimulation to induce crack propagation at the icing interface, requiring an active area of ​​less than 20%, and requiring far less energy than mainstream active deicing technologies such as electric deicing, solar thermal deicing, and hot air circulation deicing. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Schematic diagram of the implementation of the large-scale anti-icing / de-icing method of the present invention based on local interface weakening to promote interface crack propagation;

[0044] Figure 2 This is a comparison chart of ice adhesion strength on common material surfaces in Comparative Example 1;

[0045] Figure 3 Schematic diagram of the percentage of effective areas of the electric heating anti-icing / deicing technology, the photothermal anti-icing / deicing technology, the hot air circulation anti-icing / deicing technology, and the anti-icing / deicing method proposed in the present invention at different freezing temperatures in Comparative Example 2;

[0046] Figure 4 Schematic diagram of energy input power density of the electric heating anti-icing / deicing technology, the photothermal anti-icing / deicing technology, the hot air circulation anti-icing / deicing technology, and the anti-icing / deicing method proposed in the present invention at different temperatures in Comparative Example 3;

[0047] Figure 5 This is a physical picture of the large-scale anti-icing / de-icing device induced by local ultrasonic stimulation in Example 2;

[0048] Figure 6 Demonstration results of large-scale anti-icing / de-icing application induced by local ultrasonic stimulation in Example 2;

[0049] Figure 7The deicing force per unit width of the four coatings, Sylgard 184 PDMS, Ecoflex, plasticized Sylgard 184 PDMS, and plasticized Ecoflex, before and after application of local ultrasonic stimulation in Example 2;

[0050] Figure 8 This is a physical picture of the large-scale anti-icing / de-icing device using local negative pressure fluid stimulation in Example 3;

[0051] Figure 9 Demonstration results of large-scale anti-icing / de-icing application induced by local negative pressure fluid stimulation in Example 3;

[0052] Figure 10 The deicing force per unit width of the four coatings, Sylgard 184 PDMS, Ecoflex, plasticized Sylgard 184 PDMS, and plasticized Ecoflex, before and after application of local negative pressure fluid stimulation in Example 3. DETAILED DESCRIPTION

[0053] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0054] In the following description, unless otherwise specified, the reagents used are conventional commercial products, the methods used are well known in the art, and other matters not covered can be solved using existing technologies.

[0055] The present invention provides a large-scale anti-icing / de-icing method based on local interface weakening to promote interface fracture extension, such as Figure 1 As shown, it applies local stress stimulation at the edge of the loading end (the end that applies de-icing thrust) of the ice-coating interface, inducing local interface weakening, promoting the fracture extension of the ice-coating interface, and reducing the adhesion strength of the ice-coating interface.

[0056] The material type of the coating is not restricted, and the only requirement is that the initial ice adhesion strength of the coating is less than 500 kPa.

[0057] Among them, the types of local stimulation include but are not limited to local pressure fluid stimulation, local ultrasound stimulation, local electrical stimulation, local mechanical stimulation, local light stimulation, etc.

[0058] The local stimulation is preferably applied at the edge of the loading end of the ice-coating interface (the end where the deicing force is applied). The closer the local stimulation is to the starting point of the loading end of the ice-coating interface, the smaller the deicing force required. Conversely, the farther the local stimulation is from the starting point of the loading end of the ice-coating interface, the greater the deicing force required.

[0059] The applied local stimulation has an effective area less than 20% of the interface area between the ice and the coating.

[0060] Comparative Example 1

[0061] Comparison of ice adhesion strength on common material surfaces. The test conditions for ice adhesion strength on material surfaces are as follows: freezing temperature -20°C, ice length 10cm, ice width 1cm, and thickness of all coating materials 1mm. Specific experimental process: First, install a tension-compression dynamometer with an accuracy of 0.0001 Newton on a programmable motion slider. By controlling the slider to move forward, the push rod of the tension-compression dynamometer is driven to push the ice. The tension-compression dynamometer records the shear force required to remove ice on different coating surfaces. The measured shear force is divided by the area of ​​the ice interface to obtain the ice adhesion strength on the coating material surface. Figure 2 As shown in the figure, by comparing the ice adhesion strength of aluminum, polyvinyl chloride, polycarbonate, nylon, polydimethylsiloxane (PDMS), plasticized polydimethylsiloxane, silicone rubber, plasticized Ecoflex, and plasticized Ecoflex with local stimulation, it is obvious that the plasticized Ecoflex has the lowest ice adhesion strength after local stimulation, indicating that local stimulation induces interface weakening and promotes interface crack propagation, which significantly reduces the ice adhesion strength.

[0062] Comparative Example 2

[0063] Comparison of the effective areas of common anti-icing / de-icing technologies: Figure 3 As shown, by comparing the percentage of effective areas of electric heating anti-icing / deicing technology, photothermal anti-icing / deicing technology, hot air circulation anti-icing / deicing technology, and the anti-icing / deicing method proposed in the present invention at different icing temperatures. Among them, the effective area percentages of electric heating anti-icing / deicing technology and photothermal anti-icing / deicing technology are greater than 95%, and the effective area of ​​hot air circulation anti-icing / deicing technology is greater than 25% (data from literature). The effective area percentage of the anti-icing / deicing technology proposed in the present invention is less than 20%: in the large-scale deicing experiment induced by local ultrasonic stimulation, the area of ​​the ultrasonic transducer is about 40mm 2 , the area of ​​the ice interface is about 300mm 2 , the effective area percentage of local ultrasonic stimulation is about 13.3%; in the large-scale deicing experiment induced by local pressure fluid stimulation, the area of ​​the embedded flow channel is about 35mm 2 , the area of ​​the ice interface is about 300mm 2 , the effective action area percentage of local pressure fluid stimulation is about 11.7%.

[0064] It can be seen intuitively from the performance comparison that the local stimulation method adopted in this scheme can achieve an anti-icing / de-icing effect comparable to that of traditional technologies at a lower percentage of active area.

[0065] Comparative Example 3

[0066] Comparison of energy input power density of common anti-icing / de-icing technologies: Figure 4 As shown in the figure, the deicing energy consumption of electric heating anti-icing / deicing technology, light-heat anti-icing / deicing technology, hot air circulation anti-icing / deicing technology and the anti-icing / deicing technology proposed by the present invention is compared under different icing temperatures. The energy input power density of electric heating anti-icing / deicing technology and hot air circulation anti-icing / deicing technology is about 120W / m 2 -10000W / m 2 The energy input power density of the optical thermal anti-icing / de-icing technology is about 80W / m 2 -1000W / m 2 (Data from literature) The energy input power density of the anti-icing / de-icing technology proposed in this invention is: the electric energy consumed by local stimulation de-icing (the power of the ultrasonic transducer multiplied by the de-icing time, or the power of the negative pressure air pump multiplied by the de-icing time) divided by the effective area of ​​local stimulation, which is less than 20W / m 2 .

[0067] It can be seen intuitively from the performance comparison that the local stimulation method adopted in this scheme can achieve an anti-icing / de-icing effect comparable to that of traditional technologies at a lower energy input power density.

[0068] Among the above,

[0069] The test data of the non-solution in Comparative Example 1 comes from:

[0070] 1) Kevin Golovin, et al. Low-interfacial toughness materials for effective large-scale deicing. Science, 364, 371-375, 2019. DOI: 10.1126 / science.aav1266.

[0071] The test data for Comparative Examples 2 and 3 that are not based on this solution are derived from:

[0072] 1) Jiang, G., Liu, ZY & Hu, JH Superhydrophobic and Photothermal PVDF / CNTs Durable Composite Coatings for Passive Anti-Icing / Active De-Icing. AdvMater Interfaces, 2021. doi:10.1002 / admi.202101704.

[0073] 2)Li,Y.et al.One-pot synthesis of superhydrophobic photothermalmaterials with self-healing for efficient ice removal.Appl.Surf.Sci.,2022.doi:10.1016 / j.apsusc.2022.154177.

[0074] 3)Liu,Y.B.et al.Robust Photothermal Coating Strategy for EfficientIce Removal.Acs.Appl.Mater.Inter.,46981-46990,2020.doi:10.1021 / acsami.0c13367.

[0075] 4)Wu,S.W.,et al.Superhydrophobic photothermal icephobic surfacesbased on candle soot.P.Natl.Acad.Sci.USA,11240-11246,2020.doi:10.1073 / pnas.2001972117.

[0076] 5)Xie,Z.T.,et al.Carbon-Based Photothermal Superhydrophobic Materialswith Hierarchical Structure Enhances the Anti-Icing and Photothermal DeicingProperties.Acs.Appl.Mater.Inter.,48308-48321,2021.doi:10.1021 / acsami.1c15028.

[0077] 6)Zhang,S.N.et al.An electroless nickel plating fabric coated withphotothermal Chinese ink for powerful passive anti-icing / icephobic and fastactive deicing.Chem.Eng.J.,2022.doi:10.1016 / j.cej.2022.138328.

[0078] 7)Wu,B.R.et al.A superhydrophobic coating harvesting mechanicalrobustness,passive anti-icing and active de-icing performances.J.Colloid.Interf.Sci.,301-310,2021.doi:10.1016 / j.jcis.2021.01.054.

[0079] 8)Xue,C.H.et al.Superhydrophobic anti-icing coatings with self-deicing property using melanin nanoparticles from cuttlefishjuice.Chem.Eng.J.,2021,doi:10.1016 / j.cej.2021.130553.

[0080] 9)Xie,H.et al.Non-fluorinated and durable photothermalsuperhydrophobic coatings based on attapulgite nanorods for efficient anti-icing and deicing.Chem.Eng.J.,2022.doi:10.1016 / j.cej.2021.132585.

[0081] 10)Zhao,W.R.et al.Moth-eye-inspired texturing surfaces enabled self-cleaning aluminum to achieve photothermal anti-icing.Opt.Laser Technol.,2021.doi:10.1016 / j.optlastec.2021.107115.

[0082] 11) Li, NB et al. Micro / nano-cactus structured aluminum with superhydrophobicity and plasmon-enhanced photothermal trap foricephobicity. Chem. Eng. J., 2022. doi: 10.1016 / j.cej.2021.132183.

[0083] Example 1

[0084] Preparation of silicone oil plasticized Ecoflex coating: First, add 15 grams each of Ecoflex 00-30 Part A and Part B into a 100 ml beaker, use a mechanical stirrer to stir at 1000 rpm for 60 seconds, and then perform vacuum degassing to prepare a uniform Ecoflex 00-30 precursor solution. Subsequently, add 30 grams of silicone oil with a viscosity of 1000 cst to the Ecoflex 00-30 precursor solution, use a mechanical stirrer to stir at 2000 rpm for 5 minutes, and then perform vacuum degassing to complete the preparation of silicone oil plasticized Ecoflex coating, and place it in a refrigerator at 4°C for use.

[0085] Example 2

[0086] Experimental test on the surface anti-icing / de-icing of silicone oil plasticized Ecoflex coating under local ultrasonic stimulation: To further demonstrate the effectiveness of the anti-icing / de-icing method proposed in this invention, we designed a large-scale anti-icing / de-icing experimental device ( Figure 5 ): An ultrasonic transducer (rated voltage 220V, rated power 35W, operating frequency 43kHz) is embedded in and fixed to a substrate (aluminum plate), and the operating frequency is controlled by adjusting the control circuit board of the ultrasonic transducer. The effective working length of the ultrasonic transducer is approximately 5cm; a silicone oil plasticized silicone rubber composite material (Ecoflex) coating prepared in Example 1 is coated on the aluminum plate substrate, and the silicone oil plasticized silicone rubber composite material coating completely covers the ultrasonic transducer.

[0087] The deicing force of the silicone oil plasticized Ecoflex coating surface was tested before and after applying local ultrasound stimulation. Figure 6 As shown in Figure A, an aluminum plate substrate coated with silicone oil plasticized Ecoflex coating completed the icing and deicing experiment in a -20℃ cold storage. The large-scale ice length was about 30cm. Figure 6 As shown in Figure B, when the ultrasonic transducer is powered on, the de-icing force applied per unit width can be reduced from 20N / cm to 6N / cm. Moreover, when the ultrasonic transducer is powered off, large-scale ice cannot rely on gravity to separate from the coating surface ( Figure 6 C); When the ultrasonic transducer is powered on, large-scale ice detaches from the coating surface under the action of gravity ( Figure 6 F). This experiment further demonstrates that large-scale deicing can be achieved by applying local ultrasonic stimulation to induce local interface weakening.

[0088] Experiments have shown that the rated power of the ultrasonic element (ultrasonic transducer) used to generate local ultrasonic stimulation is in the range of 5W to 200W, and the operating frequency is in the range of 5kHz to 200kHz, which is effective, that is, it can effectively achieve local ultrasonic stimulation to induce large-scale anti-icing / de-icing performance.

[0089] like Figure 7 As shown in the figure, the deicing force per unit width of four coatings, PDMS, Ecoflex, plasticized PDMS, and plasticized Ecoflex, was compared before and after application of localized ultrasonic stimulation. The test results show that localized ultrasonic stimulation can reduce the deicing force per unit width of all four coatings. The experimental results effectively confirm that the proposed anti-icing / deicing method of localized stimulation-induced localized interface weakening and promoted interface fracture propagation is applicable to various types of anti-icing / deicing coatings.

[0090] Example 3

[0091] Experimental test of large-scale anti-icing / de-icing induced by local negative pressure fluid stimulation: In order to further prove the effectiveness of the anti-icing / de-icing method proposed in this invention, we designed a large-scale anti-icing / de-icing experimental device induced by local interface weakening by negative pressure fluid stimulation ( Figure 8 ), a local flow channel is manufactured inside the coating by using the reverse molding technology. The effective length of the local flow channel is about 5 cm, and it is closely attached to the substrate (aluminum plate). The negative pressure gas input by the negative pressure air pump is used to achieve local deformation of the coating at the local flow channel. The coating on the substrate is the silicone oil plasticized Ecoflex coating prepared in Example 1.

[0092] like Figure 9 As shown in Figure A, an aluminum plate substrate coated with silicone oil plasticized Ecoflex coating completed the icing and deicing experiment in a -20℃ cold storage. The large-scale ice length was about 30cm. Figure 9 As shown in B, when the negative pressure air pump is powered on, the de-icing force applied per unit width drops from 18N / cm to 5.5N / cm. Moreover, when the negative pressure air pump is powered off, large-scale ice cannot rely on gravity to separate from the coating surface ( Figure 9 C); When the negative pressure air pump is powered on, large-scale ice detaches from the coating surface under the action of gravity ( Figure 9 D) This experiment further demonstrates that large-scale deicing can be achieved by applying local negative pressure fluid stimulation to induce local interface weakening.

[0093] Experiments have shown that the input pressure used to generate local negative pressure fluid stimulation is effective in the range of -10kPa to -5MPa, that is, it can effectively achieve large-scale anti-icing / de-icing performance induced by local negative pressure fluid stimulation.

[0094] like Figure 10 As shown, a comparative test of the deicing force per unit width of four coatings, PDMS, Ecoflex, plasticized PDMS, and plasticized Ecoflex, was conducted before and after application of local negative pressure fluid stimulation. The test results show that local negative pressure fluid stimulation can reduce the deicing force per unit width of all four coatings. This experimental test result further effectively confirms that the proposed anti-icing / deicing method of local stimulation-induced local interface weakening and promoted interface fracture propagation is applicable to various types of anti-icing / deicing coatings.

[0095] In addition, experiments and simulations have found that the closer the applied local stimulation is to the application position of the deicing force, the better the final anti-icing / deicing effect will be. When the distance between the two exceeds 40mm, the effect of the local stimulation is very weak. Therefore, the application position of the local stimulation should be placed at the same position as the deicing thrust of 0-40mm, and preferably at 0mm (that is, the application position coincides).

[0096] In summary, the present invention introduces local stress stimulation at the stressed end of the interface between ice and coating to induce local interface weakening and promote the fracture extension of the interface between ice and coating. By designing a large-scale anti-icing / de-icing experiment that induces local interface weakening through local stimulation such as local negative pressure fluid and local ultrasound, and further using finite element modeling to reveal the mechanical mechanism by which local stimulation of interface weakening promotes interface fracture extension, the effectiveness of the large-scale anti-icing / de-icing method based on local stimulation of interface weakening to promote interface fracture extension disclosed in the present invention is fully verified. This method reduces the adhesion strength of the interface between ice and coating by 3-4 times, achieving large-scale anti-icing / de-icing with low energy consumption.

[0097] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention, without departing from the scope of the present invention, should be within the scope of protection of the present invention.

Claims

1. A large-scale anti-icing / de-icing method based on local interface weakening, characterized in that: The steps include: Applying local stimulation to the coating with ice layer on the surface to induce local interface weakening and promote interface fracture propagation between the ice layer and the coating, and then applying deicing thrust at the edge of the ice layer to de-ice; in, The local stimulation includes local pressure fluid stimulation, local ultrasound stimulation, local electrical stimulation, local mechanical stimulation and local light stimulation; The local stimulation is applied toward the interface between the ice layer and the coating, and the application position of the local stimulation is close to the application position of the deicing thrust.

2. A large-scale anti-icing / de-icing method based on local interface weakening according to claim 1, characterized in that: The local stimulation is local negative pressure air stimulation and / or local ultrasonic stimulation.

3. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 2, characterized in that: The local negative pressure air stimulation is applied by constructing a local flow channel inside the coating and connecting the local flow channel to a negative pressure air pump; The pressure applied by the negative pressure air pump is in the range of -10kPa to -5MPa.

4. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 2, characterized in that: The local ultrasonic stimulation is applied by an ultrasonic element attached to the surface of the coating; The ultrasonic power applied by the ultrasonic element is in the range of 5W to 200W, and the operating frequency is in the range of 5kHz to 200kHz.

5. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 1, characterized in that: The application position of the local stimulation is located within the range of 0-40 mm of the application position of the deicing thrust, wherein when the application position of the local stimulation is located at 0 mm of the application position of the deicing thrust, the application position of the local stimulation is located at the edge of the ice layer where the deicing thrust is applied.

6. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 1, characterized in that: The application area of ​​the local stimulation is less than 20% of the interface area between the ice layer and the coating.

7. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 1, characterized in that: The adhesion strength between the ice layer and the coating does not exceed 500 kPa.

8. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 1, characterized in that: The coating is a silicone rubber composite material coating plasticized with silicone oil, the elastic modulus of the coating ranges from 50kPa to 500kPa, and the adhesion strength between the coatings is less than 100kPa.

9. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 8, characterized in that: The silicone oil plasticized silicone rubber composite material coating is prepared by the following steps: Part A and Part B of Ecoflex 00-30 were stirred and mixed, followed by a first degassing treatment to obtain an Ecoflex precursor solution; Silicone oil is added to the Ecoflex precursor solution, followed by stirring and mixing, and then a second degassing treatment is performed to obtain a silicone oil plasticized Ecoflex coating.

10. The large-scale anti-icing / de-icing method based on local interface weakening according to claim 9, characterized in that: Include one or more of the following: i) Mix Part A and Part B of Ecoflex 00-30 in a mass ratio of 1:1; ii) the first degassing treatment is a vacuum degassing treatment, with stirring at a speed of 1000 rpm for 60 seconds; iii) mixing Ecoflex precursor solution and silicone oil in a mass ratio of 1:1; iv) the second degassing treatment is a vacuum degassing treatment, with stirring at a speed of 2000 rpm for 5 minutes; v) The viscosity of the silicone oil is 1000 cst.

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