A film heating device and a heating method

Abstract

The present application relates to the technical field of thin film heating, in particular to a thin film heating device and a heating method, the thin film heating device comprises a microwave radiation array layer and a coupling energy receiving layer arranged oppositely, the microwave radiation array layer is composed of a plurality of radiation units arranged closely on the same plane and regularly distributed in an array, a coaxial feed port for microwave feeding is arranged on each radiation unit; the coupling energy receiving layer is used for receiving coupling energy, an adhesion surface is arranged on the side of the coupling energy receiving layer facing the microwave radiation array layer, and the adhesion surface is used for adhesion of a thin film material to be heated. The heating device and the heating method can uniformly and effectively heat a lossy dielectric thin film, and have small volume and high energy utilization rate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thin film heating, in particular to a thin film heating device and a heating method. BACKGROUND

[0002] Hot air heating is a common heating method for heating thin films attached to the surface of a metal. This method transmits heat from the outside to the inside of the thin film in the form of heat conduction. However, because hot air is used to heat the thin film, it is a heating method from the outside to the inside, and the heating uniformity is poor. In addition, in order to achieve uniform heating, the hot air heating method needs to maintain the current environmental temperature for a long time, resulting in high energy consumption, long heating time, large equipment volume, and poor heating effect.

[0003] Chinese patent application CN 114007292 B discloses a microwave heating thin film device and system. The heating device includes a rectangular waveguide and a compression ridge. The compression ridge is arranged in the cavity of the rectangular waveguide, and a dielectric plate is arranged on the compression ridge. The compression ridge and the thin film to be heated are separated by a gap, and electromagnetic waves pass through the gap after being compressed by the compression ridge. A leakage prevention device is arranged on the rectangular waveguide to absorb / block the leakage of electromagnetic waves in the cavity. A ventilation structure is arranged in the rectangular waveguide to carry the moisture in the cavity out of the cavity. In addition, hot air can be used to accelerate the heating of the thin film. By arranging the dielectric plate on the T-shaped ridge waveguide, the original electric field distribution in the waveguide is changed, and the microwave can heat the lossy dielectric thin film attached to the metal surface. However, this heating method has the following defects: the input power of the waveguide is limited, and the uniformity of the T-shaped ridge waveguide is relatively poor because the microwave is fed from one side port. Therefore, there is still a lack of a device and method for uniformly and effectively heating lossy dielectric thin films attached to the surface of a metal in the prior art. SUMMARY

[0004] To solve the above technical problems, the purpose of the present application is to provide a thin film heating device and a heating method, which can uniformly and effectively heat lossy dielectric thin films, and have small volume and high energy utilization rate to solve the defects in the prior art.

[0005] To achieve the above technical effects, the present application adopts the following technical solutions:

[0006] In a first aspect, the present application provides a thin film heating device, comprising:

[0007] A microwave radiation array layer is composed of a plurality of radiation units arranged in a regular array on the same plane, and each of the radiation units is provided with a coaxial feed port for feeding in microwaves.

[0008] A coupling energy receiving layer is arranged opposite to the microwave radiation array layer and used for receiving microwave coupling energy, and the coupling energy receiving layer is provided with an attachment surface on the side facing the microwave radiation array layer, and the attachment surface is used for attaching the film material to be heated.

[0009] Further, the film heating device further comprises a heat preservation layer, which is arranged between the microwave radiation array layer and the coupling energy receiving layer, and the heat preservation layer has at least a first close side, which is used for close contact with the film material to be heated.

[0010] Preferably, the heat preservation layer further has a second close side, which is used for close contact with the microwave radiation array layer.

[0011] Further, the radiation unit comprises a dielectric substrate and a metal ground and a metal patch arranged on both sides of the dielectric substrate, the metal ground is arranged on the side away from the coupling energy receiving layer, and the projection area of the metal ground is greater than the projection area of the metal patch, and preferably, the dielectric substrate is preferably a dielectric ceramic material.

[0012] Further, in order to facilitate the input of microwave energy, the coaxial feed port is arranged on the side of the metal ground and at least completely penetrates the metal ground and the dielectric substrate.

[0013] Further, the geometric center of the metal patch is provided with a slot structure penetrating the metal patch, and preferably, the outer edge of the metal patch is in a regular shape, such as a rectangle, and the main purpose of arranging the slot structure is to make the coupling current generated by the radiation unit to avoid the geometric center position, so as to improve the common phenomenon of uneven heating with high middle temperature and low peripheral temperature, and the shape and size of the slot can be adjusted, and the ultimate purpose is that when microwaves of a certain frequency are input through the coaxial feed port, the microwave radiation array layer and the coupling energy receiving layer can resonate.

[0014] Further, the coupling energy receiving layer is made of a high conductivity material, and the conductivity of the high conductivity material layer is greater than 10 3 S·m -1 . Preferably, the conductivity of the high conductivity material layer is greater than 10 5 S·m -1 .

[0015] Further preferably, the high-conductivity material layer is made of a solid metal material, which is preferably any one of copper and its alloys, iron and its alloys, and aluminum and its alloys.

[0016] Further, the thin-film heating device further comprises one or more microwave sources, and the microwave radiation array layer is connected to the microwave sources through a microwave transmission device to realize generation and transmission of microwaves.

[0017] In a second aspect, the present application provides a thin-film heating method, which is to heat a thin-film material to be heated by using the thin-film heating device as described above.

[0018] Further, the thin-film material to be heated has an electrical conductivity of not less than 0.5 S·m -1 ; preferably, the thin-film material to be heated has an electrical conductivity of 2-10 5 S·m -1 ; more preferably, the thin-film material to be heated has an electrical conductivity of 10-10 2 S·m -1 .

[0019] Further, during the heating process, the thin-film material to be heated is either attached to the attachment surface of the coupling energy receiving layer in a relatively static manner or moves closely to the attachment surface of the coupling energy receiving layer to realize continuous heating.

[0020] Further, the thin-film material to be heated can be a solid thin-film material at room temperature, such as a carbon fiber reinforced polymer matrix composite (CFRP), or a liquid thin-film material at room temperature, such as a liquid water-based conductive film or a paint film with a certain electrical conductivity, or a liquid thin-film thermosetting material at room temperature, such as a thermosetting resin film.

[0021] Compared with the prior art, the present application has the following advantages:

[0022] The thin-film heating device provided by the present application uses microwaves for heating, which is high in energy efficiency and uniform in heating. In the microwave heating device, microwaves are output by a microwave source, the microwaves are radiated by a microwave radiation array layer, and the coupling energy receiving layer receives the coupled microwave energy, which is then loaded on the thin-film material to be heated by the coupling energy receiving layer, so as to realize heating of the thin-film material to be heated. The heating device and the heating method solve the defect of difficulty in heating of thin-film materials in the prior art, and the device can achieve the technical effects of uniform and efficient heating, and is not limited by input power, thus solving the defects of large size and low heating efficiency of traditional thin-film heating devices. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0024] Figure 2 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1. Figure 1 A partial enlarged view of A is shown in Figure 2.

[0025] Figure 3 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0026] Figure 4 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1. Figure 3 A partial enlarged view of B is shown in Figure 3.

[0027] Figure 5 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0028] Figure 6 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0029] Figure 7 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0030] Figure 8 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0031] Figure 9 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0032] Figure 10 A schematic diagram of the overall structure of a thin film heating device provided by the present application is shown in Figure 1.

[0033] The reference signs are: 10, coupling energy receiving layer, 20, heat preservation layer, 30, thin film material to be heated, 41, dielectric substrate, 42, metal ground, 43, metal patch, 44, slotted structure, 45, coaxial feed port. DETAILED DESCRIPTION

[0034] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0035] Unless otherwise defined, all terms used in disclosing embodiments of the application, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this application belongs. By means of example, the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counter-clockwise", "axial", "radial", "longitudinal", "circumferential", "x-direction", "y-direction", "z-direction" and the like, merely connote the orientation or position of the device or element as shown in the drawings, and are used for convenience and simplicity of description and illustration, and are not intended to indicate or imply that the device or element referred to must necessarily have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application described herein, and the terms describing the orientation or position are used only for illustrative purposes and should not be construed as limiting the patent. The terms describing the orientation or position should be understood by those skilled in the art in conjunction with the drawings, and the specific meaning of the terms should be understood according to the specific circumstances.

[0036] Embodiment 1

[0037] See Figures 1-4The embodiment provides a film heating device, which comprises a microwave source (not shown in the drawings), a microwave transmission device, a microwave radiation array layer, a heat preservation layer 20, a film material to be heated 30 and a coupling energy receiving layer 10 arranged oppositely to the microwave radiation array layer, wherein the microwave source is used for generating microwaves, the microwave transmission device is used for realizing distribution and delivery of microwave energy, in particular, the microwave transmission device comprises a power distributor and a plurality of groups of coaxial cables connected to the power distributor, the power distributor has one input port and a plurality of output ports, the input port is connected to the microwave source, the output ports are respectively connected to the plurality of groups of coaxial cables, and output ends of the coaxial cables are connected to the microwave radiation array layer to realize input of microwave energy. More specifically, the microwave radiation array layer is composed of a plurality of radiation units arranged closely on the same plane and in a regular array, each of the radiation units is provided with a coaxial feed port 45 for feeding microwaves, microwaves of a certain wavelength are fed through the coaxial feed port 45, a gap is arranged between the microwave radiation array layer and the coupling energy receiving layer 10, the heat preservation layer 20 is arranged in the gap, and two sides of the heat preservation layer 20 are respectively a first close side and a second close side, the first close side is attached to the film material to be heated 30, and the second close side is attached to the microwave radiation array layer. The arrangement of the heat preservation layer 20 can effectively isolate heat and avoid direct conduction of heat generated when the film is heated to the microwave radiation array layer, which can effectively protect the microwave radiation array layer. On the other hand, the arrangement of the heat preservation layer 20 can slow down the speed of heat dissipation, which is beneficial to heating of the film material to be heated 30. It should be particularly noted that the manufacturing material of the heat preservation layer 20 can be selected from any existing technical material that can achieve the purpose of the present application, such as an aerogel material. In addition, in order to effectively and uniformly heat the film material to be heated 30, the coupling energy receiving layer 10 is provided with an attachment surface on the side facing the microwave radiation array layer, and the film material to be heated 30 is attached to the attachment surface. It should be noted that the film material to be heated 30 can be attached to the attachment surface by any means that can achieve the purpose of the present application, for example, by any one of close attachment, adhesion and hot pressing.

[0038] In the embodiment, each radiation unit comprises a dielectric substrate 41 and a metal ground 42 and a metal patch 43 arranged on both sides of the dielectric substrate 41, the metal ground 42 and the metal patch 43 are parallel to each other, the metal ground 42 is arranged on the side away from the coupling energy receiving layer 10, and the projection area of the metal ground 42 is greater than the projection area of the metal patch 43, the dielectric substrate is selected from dielectric ceramic materials, the coaxial feed port 45 longitudinally penetrates the radiation unit, and the position of the coaxial feed port 45 should be such that the input impedance of the radiation unit is 50Ω. At the same time, in order to make the coupling current generated by the radiation unit produce an avoidance effect at the above-mentioned geometric center position, so as to improve the common phenomenon of uneven heating with high middle temperature and low peripheral temperature, the geometric center of the metal patch 43 is provided with a slot structure 44 penetrating the metal patch 43. In addition, in order to realize the feeding of microwaves, the coaxial feed port is arranged on the side of the metal ground 42 and penetrates the metal ground 42 and the dielectric substrate 41 completely, the coaxial cable comprises an inner conductor and an outer conductor, the inner conductor penetrates the inside of the coaxial feed port 42 and is welded to the metal patch 43 to realize the electrical connection between the two, and the outer conductor is electrically connected to the metal ground 42, so as to realize the connection between the coaxial cable and the radiation unit. Preferably, the inner conductor and the metal patch 43, and the outer conductor and the metal ground 42 are connected by welding to realize the electrical connection.

[0039] The principle of the embodiment is that the microwave source is used to output microwaves, the microwave radiation array layer is used to radiate microwaves, and the coupling energy receiving layer 10 is mainly used to receive the microwave energy coupled from the microwave radiation array layer. In the device, the microwave energy is coupled to the high-conductivity coupling energy receiving layer 10 through the microwave radiation array layer, and then the energy is loaded on the thin film material 30 to be heated through the coupling energy receiving layer 10, so as to realize the heating of the thin film material 30 to be heated.

[0040] In the embodiment, it needs to be particularly pointed out that the shape and size of the slot structure 44, the position of the coaxial feed port 45, the shape of the metal patch 43, the shape and size of the radiation unit, the distance between the microwave radiation array layer and the coupling energy receiving layer 10, and the material selection of the coupling energy receiving layer 10 can be adjusted according to actual needs, and the final purpose is that when microwaves of a certain frequency are input by the coaxial feed port 45, the microwave radiation array layer can resonate between the microwave radiation array layer and the coupling energy receiving layer 10, and as much energy as possible is coupled to the coupling energy receiving layer 10. Preferably, the skilled person in the art can obtain the optimal values of the above-mentioned parameters through simulation parameter scanning.

[0041] Embodiment 2

[0042] Please refer to Figures 1-4The overall structure of the thin-film heating device provided in this embodiment is the same as that in Embodiment 1. However, this embodiment provides more detailed design parameters. In this embodiment, the microwave frequency generated by the microwave source is 2.45 GHz. The radiating unit is a regular square structure, and its metal ground 42 and dielectric substrate 41 are the same in size and shape. The projected area of ​​the metal patch 43 is slightly smaller than the projected areas of the dielectric substrate 41 and the metal ground 42. Specifically, the metal patch 43 is a square patch with a side length ranging from 32 to 50 mm. Simultaneously, a slotted structure 44 is provided at the very center of the metal patch 43. The dimensions of the slotted structure 44 are designed through simulation parameter scanning to ensure that the thin-film heating device resonates at a microwave input frequency of 2.45 GHz.

[0043] Example 3

[0044] Please see Figures 1-9 In order to verify the effect of the thin-film heating device provided in Embodiment 2 above, the following simulation experiment was conducted in this embodiment:

[0045] First, electromagnetic simulation software was used for modeling and simulation. The coupling energy receiving layer 10 was made of copper plate, and the thin film material 30 to be heated had an electrical conductivity of 20 S·m. -1 A liquid aqueous conductive film with a thickness of 0.1 mm and a microwave input frequency of 2.45 GHz was constructed. During the test, a centrally coupled array unit was established, and the four adjacent faces of the coupled array unit were set as periodic boundary conditions to simulate the coupled array, thereby exploring the coupling effect of the microwave radiation array layer on the copper plate and the liquid aqueous conductive film.

[0046] During the test, the microwave coupling energy applied to the copper plate and the liquid aqueous conductive film, as well as the microwave energy input from the coaxial feed port 45 on the central radiating unit, were respectively as follows: Figure 5 , Figure 6 and Figure 7 As shown in the figure; the simulation results show that the energy loaded on the copper plate accounts for 7.68%, and the energy loaded on the liquid water-based conductive film accounts for 79.51%. The coupling energy efficiency of the system is greater than 85%, and 79.51% is also the heating efficiency of the liquid water-based conductive film. The above results show that the heating efficiency of the film heating device is good.

[0047] Meanwhile, when microwave energy is coupled from the microwave radiation array layer to the copper plate, it mainly exists in the form of coupling current. The distribution of coupling current on the copper plate surface near the microwave radiation array layer is shown in the figure. Figure 8 As shown.

[0048] In Figure 8The arrow size is proportional to the current size, and the results show that the coupling current is located close to the surface of the liquid aqueous conductive film and is uniformly distributed. According to Joule's law Q = I 2 Rt, the coupling current on a substance with certain conductivity will generate corresponding Joule heat, thereby increasing the temperature of the liquid aqueous conductive film, thereby heating the liquid aqueous conductive film, and the heating effect is uniform.

[0049] In addition, the calculation results of electromagnetic loss are coupled with the thermal field to perform multi-physical field calculation, and then the temperature distribution of the liquid aqueous conductive film can be obtained. Here, the initial temperature value of the working environment is set to 293.15K, the system works for 60s under the condition of 20W input power, and the temperature distribution of the liquid aqueous conductive film on the side of the copper plate under the condition of not considering heat dissipation is as shown in Figure 9 Figure 9 It can be seen that the liquid aqueous conductive film as a whole has a higher temperature rise, and the bulk average temperature is 730.41K, and the temperature is uniformly distributed as a whole.

[0050] Example 4

[0051] In addition to heating the film on the metal, the coupling energy receiving layer itself can also be heated. The implementation steps are similar to those of Example 3.

[0052] First, modeling and simulation are performed using electromagnetic simulation software. The conductivity of the coupling energy receiving layer is 10 6 S·m -1 The metal plate is 10S·m-1, the thickness of the coupling energy receiving layer to be heated is 1mm, and the microwave input frequency is 2.45GHz. During the test, a central coupling array unit is established, and the four adjacent surfaces of the coupling array unit are set as periodic boundary conditions to simulate the coupling array, and then the coupling effect of the microwave radiation array layer on the coupling energy receiving layer is explored.

[0053] Finally, the microwave coupling energy loaded on the coupling energy receiving layer is as shown in Figure 10 The results show that the proportion of energy loaded on the coupling energy receiving layer is 79.78%, and this value is also the heating efficiency of the device.

[0054] The above examples are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the purpose and scope of the present application, and they should be covered in the scope of the claims of the present application. The technical, shape, and structure parts not described in detail in the present application are well-known technologies.​

Claims

1. A thin-film heating device, characterized in that, include: The microwave radiation array layer consists of several radiation units arranged closely on the same plane and distributed in a regular array, and each radiation unit is provided with a coaxial feed port (45) for microwave feeding. A coupling energy receiving layer (10) is disposed opposite to the microwave radiation array layer and is used to receive coupling energy. The coupling energy receiving layer (10) has an attachment surface on the side facing the microwave radiation array layer. The attachment surface can be used for the film material (30) to be heated to attach. The radiating unit includes a dielectric substrate (41) and a metal ground (42) and a metal patch (43) disposed on both sides of the dielectric substrate (41). The metal ground (42) is disposed on the side away from the coupled energy receiving layer (10). The coaxial feed port (45) is disposed on the side of the metal ground (42) and at least completely penetrates the metal ground (42) and the dielectric substrate (41). The thin-film heating device further includes one or more microwave sources, and the microwave radiation array layer is connected to the microwave sources through a microwave transmission device; the microwave transmission device includes a power divider and multiple sets of coaxial cables connected thereto, the power divider has one input port and multiple output ports, the input port is connected to the microwave source, the output ports are respectively connected to the multiple sets of coaxial cables, and the output end of the coaxial cable is connected to the microwave radiation array layer; the coaxial cable includes an inner conductor and an outer conductor, the inner conductor extends to the inside of the coaxial feed port (45) and passes through the coaxial feed port (45) to connect to the metal patch (43), and the outer conductor is electrically connected to the metal ground (42), thereby realizing the connection between the coaxial cable and the radiation unit; It also includes a heat insulation layer (20), which is disposed between the microwave radiation array layer and the coupled energy receiving layer (10). The heat insulation layer (20) has at least one first close-fitting side, which can be attached to the film material (30) to be heated.

2. The thin-film heating device as described in claim 1, characterized in that: The projected area of ​​the metal ground (42) is larger than the projected area of ​​the metal patch (43).

3. The thin-film heating device as described in claim 2, characterized in that: The metal patch (43) has a slotted structure (44) that runs through the geometric center of the metal patch (43).

4. The thin-film heating device as described in claim 1, characterized in that: The coupled energy receiving layer (10) has at least a solid metal layer on the side closest to the microwave radiation array layer.

5. A thin-film heating method, characterized in that: The thin film heating device as described in any one of claims 1 to 4 is used to heat the thin film material (30) to be heated.

6. A thin-film heating method as described in claim 5, characterized in that, include: The thin film material (30) to be heated has an electrical conductivity of not less than 0.5 S·m. -1 Thin film materials.

7. A thin-film heating method as described in claim 6, characterized in that: During the heating process, the film material (30) to be heated is attached to the attachment surface of the coupling energy receiving layer (10) while relatively stationary, or the film material (30) to be heated moves while closely adhering to the attachment surface of the coupling energy receiving layer (10).

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