Active and passive combined de-icing method and device

Abstract

The application provides a kind of active and passive combination ice prevention method and device, including ice prevention demand surface, synthetic jet exciter, hydrophobic material layer, and hydrophobic material is pre-set on the ice prevention demand surface;When water droplet impacts the ice prevention demand surface, at this time the surface has ice prevention demand, synthetic jet exciter is used to spray jet on the ice prevention demand surface, jet is directly impacted by water droplet on the ice prevention demand surface, changes the water droplet motion trajectory and weakens the speed of water droplet impacting the ice prevention demand surface, regulates the impact dynamic characteristics of liquid droplet, reduces the contact time, the velocity gradient of jet and wall produces lift to promote liquid droplet to quickly separate and away from surface, hot jet maintains super-hydrophobic good performance, super-hydrophobic material reduces jet energy consumption, to achieve the purpose of active and passive combination ice prevention.The application can meet the large-area ice prevention demand under low energy consumption condition, reduce the cost and complexity of ice prevention device, and improve the ice prevention effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicle anti-icing, and particularly relates to a combined active and passive anti-icing method and device. BACKGROUND

[0002] Icing is a widespread natural phenomenon. Icing causes damage in many ways. For example, icing affects the power generation efficiency of wind turbines. Wind turbines are arranged in locations with good wind conditions, but these locations are often also the areas most affected by icing. Icing on the blades of wind turbines will seriously affect the power generation of the wind turbines, causing economic losses. Icing can also seriously endanger the safety of aircraft flight. Icing in different parts of an aircraft can endanger flight safety to varying degrees: icing on the lift surface can cause the aircraft to increase in drag, decrease in lift, decrease in stall angle of attack, increase in stall speed, and deterioration in controllability and stability quality; icing in the air inlet can worsen the air intake characteristics of the engine, increase the fuel consumption, reduce the service life of the engine, and even cause the engine to stall; when important instruments such as air speed tubes are iced, the on-board computer will send out incorrect information, directly affecting flight safety.

[0003] Research and exploration of effective anti- / de-icing methods have been widely concerned by scholars at home and abroad. Although anti- / de-icing research has been in-depth in recent decades, developing a more efficient, environmentally friendly, and energy-saving anti- / de-icing method is still the goal of scholars.

[0004] Currently, the main anti- / de-icing technologies that have been practically applied include hot air anti-icing, inflatable tube de-icing, electromagnetic pulse de-icing, and electric heating anti- / de-icing.

[0005] Although traditional anti- / de-icing methods can achieve good results, there are still many problems. For example, the hot air anti-icing method has problems such as low energy efficiency, reduced engine performance, and damage to materials. The inflatable tube and electromagnetic pulse de-icing methods change the aerodynamic shape, and the skin vibration generated by the latter can cause structural fatigue. The electric heating anti- / de-icing method has a high energy cost, and can also damage surface composites. In addition, traditional anti- / de-icing technologies cannot effectively achieve icing protection in some emerging hot fields. For example, existing anti- / de-icing technologies have great limitations in the application of unmanned aerial vehicles. Because unmanned aerial vehicles have less weight and can carry limited energy, and unmanned aerial vehicles are small in size and are more threatened in the same icing environment. Currently, unmanned aerial vehicles mostly use strategic anti-icing methods, i.e., avoiding icing weather to perform tasks, which severely limits their combat capabilities.

[0006] Hydrophobic materials are a promising new method of deicing with the advantages of zero energy consumption, no weight increase, etc. However, due to the micro-roughness structure on the surface of hydrophobic materials, small water droplets will impact the surface at a high speed in icing weather, thus destroying the structure. In addition, once the water droplets freeze or frost on the surface of the hydrophobic material, the material will be damaged, and its contact angle will gradually increase with the development of the icing process. Ice will also be "embedded" in the micro-structure of the hydrophobic surface, forming a larger mechanical interlocking force, which is more difficult to remove. The lack of stability and durability of hydrophobic materials under icing weather conditions seriously restricts their practical application.

[0007] In summary, the existing deicing methods have many shortcomings, and it is urgent to develop a simple structure, light weight, low energy consumption, low cost and good effect of anti-icing method. SUMMARY

[0008] In view of the problems of large energy consumption, complex structure and large weight of the existing anti-icing method, the present application provides a passive-active combined anti-icing method and device to meet the large-area anti-icing demand under low energy consumption conditions, reduce the cost and complexity of the anti-icing device, and improve the anti-icing effect.

[0009] To achieve the above technical purposes, the technical solutions of the present application are as follows:

[0010] The passive-active combined anti-icing method pre-provides a hydrophobic material on the anti-icing demand surface, and one or more synthetic jet actuators are arranged below the anti-icing demand surface, opposite the anti-icing demand surface, or the outer circumferential side of the anti-icing demand surface; when the anti-icing demand surface has anti-icing demand, the synthetic jet actuators are used to spray synthetic jets on the anti-icing demand surface and the surrounding area.

[0011] A hydrophobic material is pre-provided on the anti-icing demand surface; when a water droplet impacts the anti-icing demand surface, the anti-icing demand surface has anti-icing demand at this time, a high-speed jet is sprayed on the anti-icing demand surface by the synthetic jet actuator, the synthetic jet directly impacts the part of the anti-icing demand surface that is impacted by the water droplet, changes the trajectory of the water droplet and reduces the speed of the water droplet impacting the anti-icing demand surface, thereby reducing the collection rate of the water droplet and achieving the purpose of anti-icing. The synthetic jet can control the tangential and vertical direction speed of the water droplet before impact by adjusting the contact time and the impact dynamic characteristics of the water droplet, so as to quickly remove the water droplet. The lift generated by the jet and the wall due to the strong velocity gradient can promote the water droplet to quickly rebound and separate from the super-hydrophobic surface.

[0012] As a preferred scheme of the present application, at the part of the anti-icing demand surface where the overflow water passes, the adhesion of the water droplet on the super-hydrophobic material surface is low, and the overflow water is directly blown away by the jet generated by the synthetic jet actuator to prevent the generation of overflow ice.

[0013] As a preferred scheme of the present application, the synthetic jet actuator is a thermal synthetic jet actuator, and when the anti-icing demand surface has an anti-icing demand, the thermal synthetic jet actuator is used to spray a hot synthetic jet with a certain temperature on and near the anti-icing demand surface. A heat source is arranged inside the jet cavity of the synthetic jet actuator, the heat source heats the jet generated by the synthetic jet actuator, and then generates a hot jet to be sprayed. Further, the heat source can be any one of a ceramic heating sheet, an iron-chromium-nickel resistance wire, or a resistance net, and the heat source is arranged in the internal space of the synthetic jet actuator cavity or on the inner and outer surfaces of the cavity. The heat source can also be hot gas, and a hot gas supply source introduces hot gas with a certain temperature into the internal space of the jet cavity of the synthetic jet actuator through a heat conduction pipeline.

[0014] The present application provides a kind of active and passive combination anti-icing device, including anti-icing demand surface, synthetic jet actuator, hydrophobic material layer, there is a layer of hydrophobic material layer made of hydrophobic material on the anti-icing demand surface, synthetic jet actuator is arranged below the anti-icing demand surface or / and the opposite side of the anti-icing demand surface or / and the periphery side of the anti-icing demand surface, and synthetic jet actuator includes jet cavity, diaphragm and jet cavity outlet.

[0015] As a preferred scheme of the present application, the synthetic jet actuator has one or more jet cavity outlets, and each jet cavity outlet corresponds to a jet spray port opened on the anti-icing demand surface.

[0016] As a preferred scheme of the present application, the synthetic jet actuator has a heat source arranged inside the jet cavity, the heat source heats the jet generated by the synthetic jet actuator, and then generates a hot jet to be sprayed. Further, the heat source is not limited in form, and the heat source can be any one of a ceramic heating sheet, an iron-chromium-nickel resistance wire, or a resistance net, and the heat source is arranged in the internal space of the synthetic jet actuator cavity or on the inner and outer surfaces of the cavity. The heat source can also be hot gas, and a hot gas supply source introduces hot gas with a certain temperature into the internal space of the jet cavity of the synthetic jet actuator through a heat conduction pipeline.

[0017] As a preferred scheme of the present application, the synthetic jet actuator is a single-membrane single-cavity synthetic jet actuator or a single-membrane double-cavity synthetic jet actuator.

[0018] As a preferred scheme of the present application, the outlet of the synthetic jet actuator is a round hole or a slit, and the outlet area is tens to hundreds of square mm, and the working frequency is hundreds to thousands of hertz.

[0019] As a preferred scheme of the present application, the active and passive combined anti-icing device can be used in various occasions, such as the anti-icing demand surface is located on a translational component of an aircraft, including but not limited to a wing leading edge and a wing trailing edge; or the anti-icing demand surface is located on a rotating component of an aircraft, including but not limited to an engine rotating cap or a helicopter rotor or a wind turbine blade. Further, the supercooled water droplet particle size before icing in each application scenario is between micron and millimeter.

[0020] As a preferred scheme of the present application, the synthetic jet actuator can realize large-scale deflection of the direction of the high-speed jet flow generated by the synthetic jet actuator through control of the input electrical signal, thereby expanding the anti-icing range of a single synthetic jet actuator.

[0021] As a preferred scheme of the present application, the synthetic jet actuator can be arranged in an array mode under the anti-icing demand surface according to the size of the anti-icing demand surface and other actual needs.

[0022] As a preferred scheme of the present application, the hydrophobic material can be inorganic or organic, or a composite of multiple materials, and can be processed and prepared by electrochemical method, etching method, etc., to partially or completely cover the anti-icing demand surface. Further, the hydrophobic material is wax casting ash, polytetrafluoroethylene, polyvinylidene fluoride, polysiloxane-based viscoelastic material or polydimethylsiloxane, and the hydrophobic material is arranged on the anti-icing demand surface by using a photolithography method, an imprinting method or a spraying method.

[0023] The deicing demand surface of the present application is not limited, and can be widely applied to various fields and devices, such as aircraft, wind turbines, etc.

[0024] Compared with the prior art, the present application can obtain the following technical effects:

[0025] At present, the anti-icing methods based on thermal effect, such as hot gas anti-icing and electric heating anti-icing, have extremely high energy consumption; and the anti-icing methods based on anti-freezing fluid have serious environmental pollution problems. The surface electrodes of the DBD anti-icing method are easy to be damaged, and the energy conversion efficiency from electric energy to thermal energy is extremely low, and the energy consumption is large. The hydrophobic material which performs superior performance in a static flow field will be quickly damaged and fail in an icing environment. The active and passive combined anti-icing method and device proposed in the present application first uses the aerodynamic anti-icing principle. The synthetic jet actuator can generate a jet flow, change the motion trajectory of water droplets and weaken the speed of water droplets impacting the surface at the position directly impacted by the water droplets, thereby reducing the water droplet collection rate and achieving the purpose of anti-icing. At the position passed by the overflow water, the water droplets can be directly blown away by the jet flow to avoid the generation of overflow ice.

[0026] In addition, the heat-power coupling anti-icing principle is used. The synthetic jet exciter can generate a hot synthetic jet with vector characteristics. On the one hand, the supercooled water droplets can be heated to reduce the icing probability; on the other hand, the jet can change the running track of the water droplets to reduce the surface water droplet collection rate or directly blow the water droplets away from the surface.

[0027] Further, the active-passive combined anti-icing principle is used. The hydrophobic material plays a role in making the water droplets rebound and then be removed, and the synthetic jet can control the tangential and vertical velocity of the water droplets before impact with the super-hydrophobic surface, control the impact dynamic characteristics of the water droplets, reduce the contact time, and play a role in quickly removing the water droplets. The lift generated by the strong velocity gradient between the jet and the wall can promote the water droplets to quickly rebound and move away from the surface during the rebound process on the super-hydrophobic surface. The heating device can generate a hot jet, and the hot synthetic jet can effectively heat the hydrophobic surface to prevent the small structure of the hydrophobic material from being damaged by surface frost and ice. The hot synthetic jet can also change the running track of the water droplets and reduce the impact speed of the water droplets to avoid the water droplets from impacting and piercing the surface of the hydrophobic material; the hot synthetic jet heats the supercooled water droplets, so that the water droplets do not freeze on the surface while maintaining the Cassie state, and the performance of the hydrophobic material is fully utilized.

[0028] On the other hand, the hydrophobic material can maintain good hydrophobic performance under the protection of the hot synthetic jet, so that the impacting water droplets rebound, or the water droplets collected on the surface maintain the Cassie state and quickly pass through or quickly fall off, relieve the working pressure of the hot synthetic jet exciter, and thus reduce the overall anti-icing power.

[0029] In summary, the present application has the advantages of simple structure, light weight, and low energy consumption. Compared with the traditional electric heating and hot gas anti-icing, the hot synthetic jet and the supercooled water droplets can fully exchange heat by convection, thereby ensuring high energy efficiency. The unique aerodynamic anti-icing advantage and strong vector characteristics can ensure that it has the advantages of large-area and high-efficiency anti-icing. Further, the hot synthetic jet and the hydrophobic material achieve a complementary anti-icing effect, the hot synthetic jet fully protects the hydrophobic material, and the performance of the hydrophobic material is maximized. The hydrophobic material as a passive method relieves the working pressure and energy consumption of the hot synthetic jet, so that this active-passive method has obvious advantages in energy consumption, structure, weight, etc. compared with the previous anti-icing methods. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only show some embodiments of the present application, and those skilled in the art can obtain other drawings according to the structures shown in these drawings without any creative effort.

[0031] Figure 1 Figure 1 is a schematic diagram of a principle framework of a combined active and passive ice prevention method according to an embodiment of the present application;

[0032] Figure 2 Figure 2 is a schematic diagram of a structure according to an embodiment of the present application;

[0033] Figure 3 Figure 3 is a schematic diagram of a structure according to an embodiment of the present application;

[0034] Figure 4 Figure 4 is a schematic diagram of a structure according to an embodiment of the present application;

[0035] Figure 5 Figure 5 is a schematic diagram of a structure according to an embodiment of the present application;

[0036] Reference numerals in the drawings:

[0037] 1, ice prevention demand surface; 2, synthetic jet exciter; 201, jet cavity; 202, diaphragm; 203, jet cavity outlet; 3, jet ejection port; 4, heat source; 5, hydrophobic material layer. Specific embodiments

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0039] It should be noted that all directionality indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directionality indications also change accordingly.

[0040] In addition, the description such as “first”, “second” and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as “first”, “second” can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of “a plurality of” is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0041] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation" and the like should be understood in a broad sense, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection, or physical connection, or wireless communication connection; can be directly connected, or indirectly connected through an intermediate medium, can be internal communication of two elements or interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] In addition, the technical solutions among various embodiments of the present application can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the scope of protection required by the present application.

[0043] Reference Figure 1 In an embodiment of the present application, a kind of active and passive combined ice prevention method is provided, and hydrophobic material is arranged on the surface with ice prevention demand in advance.The material of the hydrophobic material can be inorganic material or organic material, or the composite of multiple materials.Hydrophobic material can be prepared on the surface with ice prevention demand by electrochemical method, etching method and the like, so that hydrophobic material partially or completely covers the surface with ice prevention demand.

[0044] The present application mainly realizes the active and passive ice prevention effect by using the following mechanism: the synthetic jet sprayed by the synthetic jet exciter can change the running track of water droplets and reduce the impact speed of water droplets, reduce the collection rate of water droplets while avoiding the impact of water droplets to pierce and damage the microstructure of the hydrophobic surface; the synthetic jet can control the tangential and vertical direction speed between the water droplets before impact and the hydrophobic surface, control the impact dynamic characteristics of the water droplets, reduce the contact time, and play a role in quickly removing the water droplets. The lift generated by the strong velocity gradient between the synthetic jet and the wall on the water droplets can promote the water droplets to quickly separate and move away from the surface during the rebound process on the hydrophobic surface. When the synthetic jet is a hot jet, a hot gas film can be formed on the hydrophobic surface to prevent frost on the surface, so that the hydrophobic performance of the hydrophobic surface is not reduced and fails. The supercooled water droplets are fully heated by the convective heat transfer of the hot synthetic jet, so that they do not freeze on the surface with ice prevention demand while maintaining the Cassie state, and the performance of the hydrophobic material is fully utilized. On the other hand, the hydrophobic material can overcome the defect that it is easily damaged under icing weather under the protection of the hot synthetic jet, and long-term maintain good hydrophobic performance, so that the impact water droplets rebound, or the water droplets collected on the surface maintain the Cassie state on the surface and quickly pass through or quickly fall off, thereby reducing the working power of the hot synthetic jet exciter, and achieving the purpose of active and passive combined ice prevention as a whole.

[0045] When water droplets impact the anti-icing demand surface, at which time the surface has anti-icing demand, the synthetic jet actuator is used to spray the anti-icing demand surface with a jet, which changes the trajectory of the water droplets and reduces the speed of the water droplets impacting the anti-icing demand surface, thereby reducing the water droplet collection rate and achieving the purpose of anti-icing. The synthetic jet actuator is not limited in structure and can be a single-membrane single-cavity synthetic jet actuator or a single-membrane double-cavity synthetic jet actuator.

[0046] In an embodiment of the present application, at a position on the anti-icing demand surface through which overflow water passes, the synthetic jet actuator is used to spray the position with a jet, which directly blows away the overflow water to prevent the generation of overflow ice.

[0047] In an embodiment of the present application, the synthetic jet actuator is a thermal synthetic jet actuator, which is used to spray a hot synthetic jet with a certain temperature on the anti-icing demand surface and the vicinity of the surface when the anti-icing demand surface has anti-icing demand. A heat source is arranged inside the jet cavity of the synthetic jet actuator, which heats the jet generated by the synthetic jet actuator to generate a hot jet to be sprayed out. Further, the heat source can be any one of a ceramic electric heating sheet, an iron-chromium-nickel resistance wire, or a resistance net, which is arranged in the internal space of the cavity of the synthetic jet actuator or on the inner or outer surface of the cavity. The heat source can also be hot gas, and a hot gas supply source introduces hot gas with a certain temperature into the internal space of the jet cavity of the synthetic jet actuator through a heat conduction pipeline.

[0048] In an embodiment of the present application, a combined active and passive anti-icing device is provided, which includes an anti-icing demand surface, a synthetic jet actuator, and a hydrophobic material layer, and the hydrophobic material is arranged on the anti-icing demand surface in advance. When water droplets impact the anti-icing demand surface, at which time the surface has anti-icing demand, the synthetic jet actuator is used to spray the anti-icing demand surface with a jet, which changes the trajectory of the water droplets and reduces the speed of the water droplets impacting the anti-icing demand surface, adjusts the impact dynamic characteristics of the droplets, reduces the contact time, and generates a lifting force due to the velocity gradient between the jet and the wall to promote the rapid separation and movement of the droplets away from the surface. The hot jet maintains the good performance of the super-hydrophobic material, the super-hydrophobic material reduces the energy consumption of the jet, and the purpose of combined active and passive anti-icing is achieved. The present application can meet the demand for large-area anti-icing under low energy consumption conditions, reduce the cost and complexity of the anti-icing device, and improve the anti-icing effect.

[0049] In an embodiment of the present application, a kind of active and passive combination ice prevention device is provided, including ice prevention demand surface 1, synthetic jet exciter 2, hydrophobic material layer 5, be provided with a layer of hydrophobic material layer 5 made of hydrophobic material in ice prevention demand surface 1, synthetic jet exciter is provided below ice prevention demand surface 1, synthetic jet exciter 2 includes jet cavity 201, diaphragm 202 and jet cavity outlet 203, the jet cavity outlet 203 of synthetic jet exciter 2 is aligned with the jet injection port 3 opened on ice prevention demand surface 1, a jet cavity outlet 203 is aligned with the jet injection port 3 opened on ice prevention demand surface 1.

[0050] The structure of the synthetic jet exciter 2 is not limited, and can be a single-membrane single-cavity synthetic jet exciter or a single-membrane double-cavity synthetic jet exciter.

[0051] In an embodiment of the present application, the synthetic jet exciter is provided with a heat source 4 inside the jet cavity, which heats the high-speed jet generated by the synthetic jet exciter to generate a hot jet. Further, the heat source can be any one of a ceramic electric heating sheet, an iron-chromium-nickel resistance wire or a resistance net, and the heat source 4 is arranged in the internal space of the synthetic jet exciter cavity or on the inner or outer surface of the cavity. The heat source can also be hot gas, and a hot gas supply source introduces hot gas with a certain temperature into the internal space of the synthetic jet exciter jet cavity through a heat-conducting pipeline. Figure 2 As shown in FIG. 4, a single-membrane single-cavity synthetic jet exciter with a heat source 4 is used in this embodiment, and the single-membrane single-cavity synthetic jet exciter is arranged below the ice prevention demand surface 1, and the outlet of the single-membrane single-cavity synthetic jet exciter is flush with the ice prevention demand surface 1 provided with the hydrophobic material layer 5. Figure 3 As shown in FIG. 5, a single-membrane single-cavity synthetic jet exciter with a heat source 4 is used in this embodiment, and the single-membrane single-cavity synthetic jet exciter is arranged opposite to the ice prevention demand surface 1, and the outlet of the single-membrane single-cavity synthetic jet exciter is opposite to the ice prevention demand surface 1 provided with the hydrophobic material layer 5. Figure 4 As shown in FIG. 6, a single-membrane double-cavity synthetic jet exciter with a heat source 4 is used in this embodiment, and the single-membrane double-cavity synthetic jet exciter is arranged below the ice prevention demand surface 1, and the outlet of the single-membrane double-cavity synthetic jet exciter is flush with the ice prevention demand surface 1 provided with the hydrophobic material layer 5.

[0052] The ice prevention demand surface of the present application is not limited, and can be widely used in various fields and devices, such as wind turbines and aircraft. Figure 5As shown, the embodiment is a schematic diagram of the active and passive combined anti-icing device provided by the present application for wing anti-icing, that is, the anti-icing demand surface 1 is the wing surface. In actual application, the number of synthetic jet actuators is determined according to the size of the surface having anti-icing demand. Specifically, according to the geometric characteristics of the surface having anti-icing demand and factors such as icing temperature and thickness, a plurality of synthetic jet actuators are arranged in an array at a certain interval. The synthetic jet actuators can realize large-range deflection of the direction of the high-speed jet flow generated thereby by controlling the input electrical signal, thereby expanding the anti-icing range of a single synthetic jet actuator.

[0053] Anti-icing by using the active and passive combined anti-icing device, comprising the following steps:

[0054] Step one: a hydrophobic material layer is pre-set on the surface having anti-icing demand.

[0055] Step two: during anti-icing, the diaphragm inside the synthetic jet actuator or / and the heat source can be turned on as needed, and at the same time, large-angle deflection of the jet flow can be realized by changing the input electrical signal of the diaphragm.

[0056] Step three: at the end of anti-icing, the diaphragm and the heat source are turned off, and the next anti-icing is waited.

[0057] The remaining matters of the present application are known technologies.

[0058] The technical features of the above embodiments can be combined arbitrarily, and in order to make the description concise, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0059] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the patent protection scope of the present application should be subject to the appended claims.

Claims

1. A combined active and passive anti-icing method, characterized in that: A hydrophobic material is pre-placed on the surface requiring anti-icing, and one or more synthetic jet actuators are arranged below the surface requiring anti-icing or / and on the opposite side of the surface requiring anti-icing or / and on the outer periphery of the surface requiring anti-icing; the synthetic jet actuator is a thermal synthetic jet actuator, and a heat source is provided inside the jet cavity of the synthetic jet actuator. The heat source heats the jet generated by the synthetic jet actuator, thereby generating a thermal jet that is ejected. When the surface requiring anti-icing has an anti-icing requirement, a thermally synthesized jet exciter is used to spray a thermally heated jet at a certain temperature onto the surface and its vicinity. The thermally heated jet forms a thermal gas film on the hydrophobic surface, preventing frost formation that would reduce or disable the hydrophobic properties of the surface. The thermally synthesized jet fully heats the supercooled water droplets through convective heat transfer, ensuring that the droplets remain in a Cassie state while preventing icing on the surface requiring anti-icing, thus fully utilizing the properties of the hydrophobic material. The hot jet directly impacts the water droplets on the surface requiring anti-icing, altering the droplet trajectory and reducing the speed at which the droplets hit the surface, thereby reducing the droplet collection rate and achieving the purpose of anti-icing. The thermal jet modulates the impact dynamics of the water droplet by controlling the tangential and perpendicular velocities between the water droplet and the superhydrophobic surface before impact, thereby reducing the contact time and enabling rapid removal of the water droplet. The lift generated by the strong velocity gradient between the thermal jet and the wall promotes the rapid detachment of the water droplet from the superhydrophobic surface during its rebound process.

2. The active-passive combined anti-icing method according to claim 1, characterized in that: In areas where overflow water passes over surfaces requiring anti-icing, water droplets have low adhesion to the superhydrophobic material surface. By generating a jet through a synthetic jet exciter, the overflow water is directly blown away, preventing the formation of overflow ice.

3. The active-passive combined anti-icing method according to claim 1 or 2, characterized in that: The heat source is a ceramic heating element, an iron-chromium-nickel resistance wire, or a resistance grid, and the heat source is located inside the cavity of the synthetic jet exciter or on the inner or outer surface of the cavity.

4. The active-passive combined anti-icing method according to claim 1 or 2, characterized in that: The heat source is hot gas, and the hot gas supply source introduces hot gas with a certain temperature into the jet cavity of the synthetic jet exciter through a heat conduction pipe.

5. An active-passive combined anti-icing device for implementing the active-passive combined anti-icing method as described in claim 1 or 2, characterized in that: The device includes an anti-icing required surface, a synthetic jet actuator, and a hydrophobic material layer. A hydrophobic material layer is disposed on the anti-icing required surface. A synthetic jet actuator is disposed below the anti-icing required surface and / or on the opposite side of the anti-icing required surface and / or on the outer periphery of the anti-icing required surface. The synthetic jet actuator includes a jet cavity, a vibrating diaphragm, and a jet cavity outlet. A heat source is disposed inside the jet cavity of the synthetic jet actuator. The heat source heats the jet generated by the synthetic jet actuator, thereby generating a hot jet that is ejected.

6. The active-passive combined anti-icing device according to claim 5, characterized in that: The heat source is a ceramic heating element, an iron-chromium-nickel resistance wire, or a resistance grid, and the heat source is located in the internal space of the synthetic jet exciter cavity or on the inner or outer surface of the cavity; or the heat source is hot gas, and the hot gas supply source introduces hot gas with a certain temperature into the interior of the synthetic jet exciter's jet cavity through a heat-conducting pipe.

7. The active-passive combined anti-icing device according to claim 5, characterized in that: The outlet of the synthetic jet exciter is a circular hole or slit with an outlet area of ​​tens to hundreds of square millimeters and an operating frequency of hundreds to thousands of hertz.

8. The active-passive combined anti-icing device according to claim 5, characterized in that: The anti-icing required surface is located on the translational components of the aircraft, including the leading edge and trailing edge of the wing; or the anti-icing required surface is located on the rotating components of the aircraft, including the engine shroud, helicopter rotor, or wind turbine blade.

9. The active-passive combined anti-icing device according to claim 7 or 8, characterized in that: The hydrophobic material is wax casting ash, polytetrafluoroethylene, polyvinylidene fluoride, polysiloxane viscoelastic material or polydimethylsiloxane. The hydrophobic material is applied to the surface requiring anti-icing by photolithography, embossing or spraying.

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