A wave-transmitting heating film

Abstract

The present application relates to the field of heating devices, and in particular to a wave-permeable heating film, and in particular to a wave-permeable heating film, which includes a microchannel membrane and a microchannel arranged in the microchannel membrane, the two ends of the microchannel penetrate to the outside of the microchannel membrane, a pair of interfaces that are conductive and can pass liquid are installed in the microchannel, and the two ends of the microchannel are respectively connected to a propeller through the interface, and the propeller includes a first microchannel propeller and a second microchannel propeller respectively connected to the two interfaces, and the first microchannel propeller is filled with conductive liquid metal that can fill the entire microchannel. The heating film can be switched between conductive heating and non-conductive wave-permeable states, and the present application has the effect of enabling the heating film to have the functions of heating and wave-permeability at the same time.

Description

Technical Field

[0001] The present application relates to the field of heating devices, and in particular to a wave-transmissive heating film. Background Art

[0002] Heating film technology has been widely used in various fields, such as thermal insulation and heating of equipment or spaces, anti-icing / de-icing on the surfaces of aircraft and other equipment, etc.

[0003] All kinds of heating films basically have heating resistors built into the heating films. Based on the principle of Joule's law, a certain power source is applied to the heating resistor to achieve the purpose of electric heating. This principle of electric heating films requires good electrical conductivity. Some equipment surfaces not only have heating requirements but also wave transmission requirements. For example, the surface of an aircraft often has stealth requirements. The main principle of a stealth aircraft is that when the radar emits rays to continue detecting the aircraft, the aircraft itself is made of wave-transmitting materials, so that the rays emitted by the radar can penetrate the aircraft itself, and the radar cannot detect the existence of the aircraft. Therefore, the surface of the aircraft with stealth requirements has wave transmission requirements.

[0004] Traditional heating films have good electrical conductivity, so they have strong reflective ability for electromagnetic waves. Traditional heating films are not suitable for use on the surface of equipment that requires wave transmission. Therefore, traditional heating films cannot achieve compatible heating and wave transmission functions. Summary of the invention

[0005] In order to enable the heating film to have both heating and wave-transmitting functions, the present application provides a wave-transmitting heating film.

[0006] The wave-transmissive heating film provided in the present application adopts the following technical solution:

[0007] A wave-transmissive heating film comprises a microchannel membrane and a microchannel arranged in the microchannel membrane, wherein both ends of the microchannel extend to the outside of the microchannel membrane, a pair of interfaces that are conductive and can pass liquid are installed in the microchannel, and both ends of the microchannel are respectively connected to a propeller through the interfaces, and the propeller comprises a first microchannel propeller and a second microchannel propeller respectively connected to the two interfaces, and the first microchannel propeller is filled with conductive liquid metal that can fill the entire microchannel.

[0008] By adopting the above technical scheme, the purpose of using electrodes to heat the heating film is achieved by filling liquid metal in the microchannel. The liquid metal can move freely in the microchannel. When the heating function of the heating film is not needed, the liquid metal in the microchannel is extracted from the microchannel by the first microchannel propeller, and the liquid metal flows into the first microchannel propeller. There is no liquid metal filled in the microchannel, so that the entire microchannel membrane can have a better wave transmission function, realizing the stealth function of the aircraft. When the heating function of the heating film needs to be used again, the first microchannel propeller is used to push the liquid metal into the microchannel, and the two ends of the liquid metal flow to the position in contact with the two electrodes. The two electrodes pressurize the liquid metal, and the liquid metal is heated and heated, thereby realizing the heating function of the heating film, so that the heating film can be switched between conductive heating and non-conductive wave transmission states.

[0009] Optionally, the second microfluidic channel propeller is filled with an immiscible liquid that is immiscible with the liquid metal, and the immiscible liquid has wave-transmitting properties.

[0010] By adopting the above technical solution, the second microchannel propeller is filled with immiscible liquid. When the conductive heating function of the microchannel membrane is not needed, the second microchannel propeller propels the immiscible liquid into the microchannel from the end away from the first microchannel propeller. The liquid metal in the microchannel is pushed into the first microchannel syringe. At this time, there is no air to fill the microchannel, which effectively reduces the interference of air on the wave permeability of the entire heating film.

[0011] Optionally, the relative dielectric constants of the microfluidic membrane and the immiscible liquid are both less than 2.8.

[0012] Optionally, the relative dielectric constant of the microfluidic membrane and the immiscible liquid differs by less than 0.5.

[0013] By adopting the above technical solution, the dielectric constant of the material of the microchannel membrane is close to that of the immiscible liquid, thereby reducing the reflected waves caused by the difference in dielectric constants between the microchannel membrane and the immiscible liquid when the immiscible liquid fills the microchannel, thereby improving the wave transmission performance of the entire heating film.

[0014] Optionally, the microfluidic channel membrane is a microfluidic channel membrane made of a polymer of a low dielectric constant non-polar material.

[0015] By adopting the above technical solution, the microfluidic membrane with a low dielectric constant can ensure that the entire microfluidic membrane has good wave transmission performance as a whole.

[0016] Optionally, the room temperature kinematic viscosity of the immiscible liquid is less than 200 square millimeters per second and the freezing point is lower than -20°C.

[0017] By adopting the above technical solution, the fluidity of the immiscible liquid is good, so that the resistance of the immiscible liquid when flowing in the microchannel is small, and the freezing point of the immiscible liquid is low, which can effectively avoid the freezing and solidification of the immiscible liquid under low temperature conditions, thereby maintaining the functional switching of the entire heating film.

[0018] Optionally, the interface includes a first electrode plate and a second electrode plate for conducting electricity, a first flow channel is fixed to a side of the first electrode plate close to the second electrode plate, a second flow channel is fixed to a side of the second electrode plate close to the first electrode plate, an outer diameter of the first flow channel is equal to an inner diameter of the second flow channel, and the first flow channel is inserted into the inner side of the second flow channel to form an interference fit.

[0019] By adopting the above technical solution, since the outer diameter of the first flow channel is equal to the inner diameter of the second flow channel, the first flow channel and the second flow channel are interference fit after insertion, and the liquid in the microchannel flows in and out through the interface, thereby ensuring the internal pressure of the microchannel is stable and the internal liquid flows smoothly.

[0020] Optionally, the interface includes a first opening provided on one side of the first flow channel, and the second electrode plate is provided with a third opening.

[0021] By adopting the above technical solution, the flow of liquid in and out of the microchannel can be ensured through the first opening and the third opening, and the channel for liquid flow is single, thereby reducing the possibility of liquid flowing out from other openings.

[0022] In summary, the present application includes at least one of the following beneficial technical effects:

[0023] 1. The purpose of heating the heating film by using the electrode is achieved by filling the microchannel with liquid metal, and the liquid metal can move freely in the microchannel; when the heating function of the heating film is not needed, the liquid metal in the microchannel is extracted from the microchannel by the first microchannel propeller, and the liquid metal flows into the first microchannel propeller. There is no liquid metal filling in the microchannel, so that the entire microchannel membrane can have a better wave-transmitting function, and the stealth function of the aircraft is realized; when the heating function of the heating film needs to be used again, the first microchannel propeller is used to push the liquid metal into the microchannel, and the two ends of the liquid metal flow to the position in contact with the two electrodes. The two electrodes pressurize the liquid metal, and the liquid metal is heated and heated, thereby realizing the heating function of the heating film, so that the heating film can be switched between the conductive heating and non-conductive wave-transmitting states;

[0024] 2. Fill the second microchannel propeller with immiscible liquid. When the conductive heating function of the microchannel membrane is not needed, the second microchannel propeller pushes the immiscible liquid into the microchannel from the end away from the first microchannel propeller. The liquid metal in the microchannel is pushed into the first microchannel syringe. At this time, there is no air to fill the microchannel, which effectively reduces the interference of air on the wave permeability of the entire heating film. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application.

[0026] Figure 2 It is an exploded diagram of the interface in the embodiment of the present application.

[0027] Figure 3 It is a structural diagram of the interface in the embodiment of the present application.

[0028] Figure 4 It is a schematic diagram of a replacement scheme of the propulsion member in state two in an embodiment of the present application.

[0029] Figure 5 It is a schematic diagram of a replacement scheme of the propulsion member in state one in an embodiment of the present application.

[0030] Figure 6 It is a structural block diagram of some devices installed on the liquid pipeline in the embodiment of the present application.

[0031] Explanation of the accompanying drawings: 1. Microfluidic membrane; 2. Microfluidic channel; 3. Interface; 31. First metal interface; 311. First electrode plate; 312. First channel; 3121. First opening; 32. Second metal interface; 321. Second electrode plate; 3211. Third opening; 322. Second channel; 3221. Second opening; 4. Propeller; 41. First microfluidic channel propeller; 42. Second microfluidic channel propeller; 6. Liquid metal; 7. Immiscible liquid; 8. Liquid pipeline; 81. One-way throttle valve; 82. Liquid drive member; 83. Pressure reducing valve. DETAILED DESCRIPTION

[0032] The following is combined with Figure 1-6 This application is described in further detail.

[0033] The present application embodiment discloses a wave-transmissive heating film. Figure 1 The heating film includes a microfluidic membrane 1 and a microfluidic channel 2 arranged in the microfluidic membrane 1; an interface 3 is respectively arranged at the head and tail ends of the microfluidic channel 2, the microfluidic channel 2 is filled with liquid, and the two interfaces 3 of the microfluidic channel 2 are respectively connected to a propeller 4, and the propeller 4 includes a first microfluidic channel propeller 41 and a second microfluidic channel propeller 42.

[0034] The microchannel 2 is bent and spiraled in the microchannel membrane 1. In this embodiment, the microchannel membrane 1 is a membrane of a polymer matrix. The polymer matrix material can be selected from low dielectric constant and non-polar materials such as polydimethylsiloxane, polyacetamide, polyetheretherketone, styrene-butadiene rubber, epoxy resin, polyurethane, etc. The low dielectric constant material can ensure the overall wave transmission performance of the heating film.

[0035] The cross section of the microchannel 2 can be a circle with a diameter of 1-2 mm or a square with a side length of 1-2 mm. Without affecting the flow of liquid, it occupies a smaller thickness of the entire heating film. The microchannel 2 can be manufactured by mold replication, laser engraving, embossing, etc.

[0036] Reference Figure 2 The interface 3 includes a first metal interface 31 and a second metal interface 32. The first metal interface 31 includes a first electrode plate 311 and a first flow channel 312 fixed to the first electrode plate 311. The first electrode plate 311 is disc-shaped, the first flow channel 312 is a tube with openings at both ends, and the annular side of the first flow channel 312 is provided with a first opening 3121.

[0037] The second metal interface 32 includes a disc-shaped second electrode plate 321 and a second flow channel 322 fixed to the second electrode plate 321. The second flow channel 322 is also in the shape of a tube with openings at both ends, and a second opening 3221 is provided on the side of the second flow channel 322. A third opening 3211 is provided through the second electrode plate 321, and the third opening 3211 is connected to the second flow channel 322. The materials of the first electrode plate 311 and the second electrode plate 321 include but are not limited to copper, aluminum and other alloy conductive materials.

[0038] Reference Figure 2 , Figure 3 The outer diameter of the first flow channel 312 is equal to the inner diameter of the second flow channel 322. The first flow channel 312 is inserted into the inner side of the second flow channel 322 so that the first flow channel 312 and the second flow channel 322 are interference fit, and the first opening 3121 is connected to the second opening 3221, and each interface 3 is provided with two openings for liquid flow.

[0039] When in use, the liquid in the microchannel 2 flows along the first opening 3121 and the third opening 3211. Since the first channel 312 and the second channel 322 are partially interference fit, the internal pressure of the microchannel 2 is guaranteed to be stable and the internal liquid flows smoothly.

[0040] Reference Figure 1 , Figure 3A wire is also connected between the two interfaces 3, and a power source for applying voltage is connected to the wire. The first electrode plate 311 or the second electrode plate 321 of each interface 3 is connected to the wire, and then conduction is performed with the help of the first electrode plate 311 or the second electrode plate 321.

[0041] Reference Figure 1 , the first microchannel propeller 41 is filled with liquid metal 6 or immiscible liquid 7, and the second microchannel propeller 42 is filled with liquid metal 6 or immiscible liquid 7, and the liquids filled in the first microchannel propeller 41 and the second microchannel propeller 42 are different. The immiscible liquid 7 cannot be dissolved in the liquid metal 6, and the liquid metal 6 and the immiscible liquid 7 are respectively filled into the microchannel 2 through the two interfaces 3, and the volume of the liquid metal 6 or the immiscible liquid 7 can fill the entire microchannel 2.

[0042] Reference Figure 1 , Figure 4 The first microfluidic propeller 41 and the second microfluidic propeller 42 can be various types of syringes, injection pumps, etc. Since one of the first microfluidic propeller 41 and the second microfluidic propeller 42 pushes out when the other one pushes forward, the first microfluidic propeller 41 and the second microfluidic propeller 42 always perform opposite actions synchronously, and a synchronous driving device can also be used to achieve linkage.

[0043] Reference Figure 1 The liquid metal 6 in this embodiment is selected from materials with a low melting point (i.e., the melting point is below 10°C, the melting point is the solidification point, if the melting point is too high, it is solid at room temperature and cannot flow (generally the anti-icing temperature is below 20°C)) that can flow freely in the microchannel 2, such as alloys of metals such as gallium, indium, and tin, which can directly generate Joule heat after being connected to direct current or alternating current.

[0044] The immiscible liquid 7 in this embodiment can be selected from methyl silicone oil, amino silicone oil, liquid paraffin, low melting point lubricating liquid and other liquids that are immiscible with the liquid metal 6. At the same time, the immiscible liquid 7 is non-conductive, and the room temperature kinematic viscosity of the immiscible liquid is less than 200 square millimeters per second, and the freezing point is lower than -20°C.

[0045] When selecting the immiscible liquid 7 and the polymer matrix for making the microfluidic membrane 1, the dielectric constants thereof should be measured and investigated first. When the relative dielectric constants of the two are less than 2.8 and the difference is less than 0.5, the microfluidic membrane 1 and the immiscible liquid 7 that meet this condition will have the least interference with electromagnetic waves. This can reduce the reflected waves caused by the difference in dielectric constants between the microfluidic channel 2 and the immiscible liquid 7 in state 2, and optimize the overall wave transmission of the heating film (the experiment uses dimethyl silicone oil + polydimethylsiloxane, and the dielectric constants of the liquid and the polymer matrix are close for the best).

[0046] Reference Figure 5 When the propulsion member 4 pushes the liquid metal 6 to fill the microchannel 2, this state is defined as state 1 in the present embodiment. The liquid metal 6, the two interfaces 3 and the wire form a passage. At this time, the wire is energized. Due to the good conductive property of the liquid metal 6, the liquid metal 6 is turned on, and the liquid metal 6 is heated by the two electrodes, and the heating film is in a heating state.

[0047] Reference Figure 4 When the immiscible liquid 7 fills the microchannel 2, this embodiment defines this state as the initial state (also called state 2). At this time, since the immiscible liquid 7 is not conductive, the immiscible liquid 7, the two interfaces 3 and the wires cannot form a passage, and then the heating film cannot be heated, so that the heating film is in a wave-transmitting state.

[0048] In the initial state, the microfluidic channel 2 is filled with the immiscible liquid 7. At this time, the liquid in the microfluidic channel 2 is neither conductive nor heatable, but has good wave transmission performance and can meet the stealth requirements of the aircraft.

[0049] Reference Figure 5 In state one, the propeller 4 pushes the liquid metal 6 into the microchannel 2. At the same time, the immiscible liquid 7 is pushed out by the liquid metal 6 in the microchannel 2 until the liquid metal 6 fills the entire microchannel 2. The interfaces 3 at both ends of the microchannel 2 are connected. After DC or AC power is connected, the liquid metal 6 generates Joule heat. At this time, the conductive performance of the heating film is good, but the wave transmission performance is poor.

[0050] Reference Figure 4 On the contrary, in state 2, the pusher 4 pushes the immiscible liquid 7 into the microchannel 2, and the liquid metal 6 is pushed out at the same time, until the immiscible liquid 7 fills the entire microchannel 2, so as to empty the liquid metal 6 from the microchannel 2 with built-in electrodes, thereby disconnecting the conductive circuit inside the microchannel 2. At this time, the heating film loses its conductivity, but has better wave transmission performance. By filling or emptying the liquid metal 6, the switching between the conductive heating performance and the insulating wave transmission performance of the microchannel film 1 is achieved, thereby realizing the controllable wave transmission of the heating film.

[0051] Reference Figure 6 Here, a liquid pipeline 8 is provided between the first microfluidic propeller 41 and one of the interfaces 3, and the second microfluidic propeller 42 is also connected to the other interface 3 and is provided with the same liquid pipeline 8. Here, the liquid pipeline 8 connected to the first microfluidic propeller 41 is taken as an example for introduction.

[0052] A one-way throttle valve 81 is installed on the liquid pipeline 8, and the one-way throttle valve 81 is used to ensure smooth switching of the two liquids in the microchannel 2. A liquid driving member 82 is also installed on the liquid pipeline 8, and the liquid in the first microchannel propeller 41 can be pumped out or withdrawn by the liquid driving member 82. Here, the liquid driving member 82 is a hydraulic pump.

[0053] A pressure reducing valve 83 is also installed between the one-way throttle valve 81 and the first microchannel propeller 41 , and the liquid pipeline 8 is protected by the pressure reducing valve 83 to reduce the possibility of overpressure in the liquid pipeline 8 , thereby protecting the liquid pipeline 8 .

[0054] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A wave-transmissive heating film, characterized in that: The invention comprises a microfluidic membrane (1) and a microfluidic channel (2) arranged in the microfluidic membrane (1), wherein two ends of the microfluidic channel (2) extend to the outside of the microfluidic membrane (1), a pair of interfaces (3) capable of conducting electricity and passing liquid are installed in the microfluidic channel (2), and two ends of the microfluidic channel (2) are respectively connected to a propulsion member (4) through the interfaces (3), and the propulsion member (4) comprises a first microfluidic channel propeller (41) and a second microfluidic channel propeller (42) respectively connected to the two interfaces (3), and the first microfluidic channel propeller (41) is filled with a conductive liquid metal (6) capable of filling the entire microfluidic channel (2); The second microchannel propeller (42) is filled with an immiscible liquid (7) that is immiscible with the liquid metal (6), and the immiscible liquid (7) has a wave-transmitting property; The microfluidic channel membrane (1) is a microfluidic channel membrane (1) made of a polymer of a low dielectric constant non-polar material.

2. The wave-transmissive heating film according to claim 1, characterized in that: The relative dielectric constants of the microfluidic membrane (1) and the immiscible liquid (7) are both less than 2.

8.

3. The wave-transmissive heating film according to claim 1, characterized in that: The relative dielectric constant of the microfluidic membrane (1) and the immiscible liquid (7) differs by less than 0.

5.

4. The wave-transmissive heating film according to claim 1, characterized in that: The room temperature kinematic viscosity of the immiscible liquid (7) is less than 200 square millimeters per second, and the freezing point is lower than -20°C.

5. The wave-transmissive heating film according to claim 1, characterized in that: The interface (3) comprises a first electrode plate (311) and a second electrode plate (321) for conducting electricity; a first flow channel (312) is fixed on a side of the first electrode plate (311) close to the second electrode plate (321); a second flow channel (322) is fixed on a side of the second electrode plate (321) close to the first electrode plate (311); an outer diameter of the first flow channel (312) is equal to an inner diameter of the second flow channel (322); and the first flow channel (312) is plugged into the inner side of the second flow channel (322) to form an interference fit.

6. The wave-transmissive heating film according to claim 5, characterized in that: The interface (3) comprises a first opening (3121) provided on one side of the first flow channel (312), and the second electrode plate (321) is provided with a third opening (3211).

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