CN114526623A - Flat plate type thermal diode, preparation method thereof and solar heat collector - Google Patents
Flat plate type thermal diode, preparation method thereof and solar heat collector Download PDFInfo
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- CN114526623A CN114526623A CN202210156312.6A CN202210156312A CN114526623A CN 114526623 A CN114526623 A CN 114526623A CN 202210156312 A CN202210156312 A CN 202210156312A CN 114526623 A CN114526623 A CN 114526623A
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- 238000002360 preparation method Methods 0.000 title abstract description 11
- 230000002209 hydrophobic effect Effects 0.000 claims abstract description 61
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 47
- 238000012546 transfer Methods 0.000 claims abstract description 38
- 238000007789 sealing Methods 0.000 claims abstract description 19
- 238000000034 method Methods 0.000 claims abstract description 3
- SQGYOTSLMSWVJD-UHFFFAOYSA-N silver(1+) nitrate Chemical compound [Ag+].[O-]N(=O)=O SQGYOTSLMSWVJD-UHFFFAOYSA-N 0.000 claims description 20
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 10
- 238000001035 drying Methods 0.000 claims description 10
- XPBBUZJBQWWFFJ-UHFFFAOYSA-N fluorosilane Chemical compound [SiH3]F XPBBUZJBQWWFFJ-UHFFFAOYSA-N 0.000 claims description 10
- 229910001961 silver nitrate Inorganic materials 0.000 claims description 10
- 239000008367 deionised water Substances 0.000 claims description 9
- 229910021641 deionized water Inorganic materials 0.000 claims description 9
- 238000011049 filling Methods 0.000 claims description 9
- 238000005245 sintering Methods 0.000 claims description 8
- 238000012986 modification Methods 0.000 claims description 7
- 230000004048 modification Effects 0.000 claims description 7
- -1 polytetrafluoroethylene Polymers 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 5
- 229910000838 Al alloy Inorganic materials 0.000 claims description 4
- 238000006056 electrooxidation reaction Methods 0.000 claims description 4
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 4
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 4
- 239000011148 porous material Substances 0.000 claims description 4
- 230000003075 superhydrophobic effect Effects 0.000 claims description 4
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 claims description 3
- 239000004743 Polypropylene Substances 0.000 claims description 3
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- 229920001971 elastomer Polymers 0.000 claims description 3
- 238000005530 etching Methods 0.000 claims description 3
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- 239000004814 polyurethane Substances 0.000 claims description 3
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/0233—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes the conduits having a particular shape, e.g. non-circular cross-section, annular
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
- F24S10/00—Solar heat collectors using working fluids
- F24S10/90—Solar heat collectors using working fluids using internal thermosiphonic circulation
- F24S10/95—Solar heat collectors using working fluids using internal thermosiphonic circulation having evaporator sections and condenser sections, e.g. heat pipes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/04—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with tubes having a capillary structure
- F28D15/046—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with tubes having a capillary structure characterised by the material or the construction of the capillary structure
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/40—Solar thermal energy, e.g. solar towers
- Y02E10/44—Heat exchange systems
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
Abstract
The invention provides a flat thermal diode, a preparation method thereof and a solar thermal collector, and relates to the technical field of thermal diodes. Specifically, the planar thermal diode includes a hydrophilic plate, a hydrophobic plate, and a seal disposed between the hydrophilic plate and the hydrophobic plate; at least one closed cavity formed among the hydrophilic plate, the hydrophobic plate and the sealing element is a water vapor area, and the water vapor area is used for bearing heat transfer working media; in the steam area, the surface of hydrophilic board is provided with the capillary core. The flat plate type thermal diode has excellent unidirectional heat transfer capability and reverse heat insulation capability, controllable energy transfer direction and high heat transfer efficiency; meanwhile, the method has certain designability and can meet the requirements of different scenes on heat transfer.
Description
Technical Field
The invention relates to the technical field of thermal diodes, in particular to a flat plate type thermal diode, a preparation method thereof and a solar thermal collector.
Background
The thermal diode is a high-efficiency heat transfer element, has the advantages of unidirectional heat transfer, controllable heat flow, high heat transfer efficiency and the like, and has the characteristics of compact volume, light weight, no noise, no transmission part and the like. Under the background of a double-carbon strategy, the thermal diode has wide application prospects and potential market values in the fields of energy storage, energy conservation, heat preservation and the like, and can replace the original heat transfer workpiece no matter in combination with new energy, in the aspects of traditional chemical heat transfer and heat recovery, or in the aspects of heat conduction and heat dissipation of precise devices in the field of mechanical electronics. However, the application and popularization of the thermal diode still belong to the starting stage, the two-phase flow and material design and related theoretical calculation are not mature, and the problems of high cost, high marketing difficulty and the like exist.
At present, a common thermal diode in the market is a gravity type thermal diode, after a working medium is heated and vaporized in an evaporation section, the working medium flows down to a condensation pipe under the action of a gravity field and an accelerated pressure difference, heat is released and converted into liquid, the condensate flows back to the evaporation section under the action of gravity, and circulation is formed. For the gravity thermal diode, the condensation section must be positioned above the evaporation section when in use, so that certain limitations exist in design and application. A thermal diode which does not rely on gravity, such as CN202110633764.4, discloses an ultrathin thermal diode based on a gas-liquid coplanar structure and a preparation method thereof, wherein a main trunk liquid absorption core and an auxiliary liquid absorption core with a porous structure are arranged to realize the flow of a liquid working medium; because the structure of the liquid absorption core is more complex, the preparation process is complicated, the sealing performance of the liquid absorption core and the shell structure needs to be maintained after the liquid absorption core is put into use, and the production cost is very high.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
The first object of the present invention is to provide a flat type thermal diode having excellent unidirectional heat transfer capability and reverse heat insulation capability, controllable energy transfer direction, and high heat transfer efficiency.
The second purpose of the invention is to provide a preparation method of the flat plate type thermal diode, which is simple and feasible and is suitable for mass production; the design is high, and the requirements of different scenes on heat transfer can be met.
The third purpose of the present invention is to provide a solar heat collector, which includes the flat thermal diode and has the advantage of high heat transfer efficiency.
In order to achieve the above purpose of the present invention, the following technical solutions are adopted:
a flat thermal diode comprising a hydrophilic plate, a hydrophobic plate, and a seal disposed between the hydrophilic plate and the hydrophobic plate; at least one closed cavity formed among the hydrophilic plate, the hydrophobic plate and the sealing element is a water vapor area, and the water vapor area is used for bearing heat transfer working media.
And in the water vapor area, the surface of the hydrophilic plate is provided with a capillary core.
Preferably, the porosity of the capillary core is 45% -55%, and the pore diameter of the capillary core is 50-150 μm;
preferably, the capillary wick is obtained by sintering aluminum powder;
more preferably, the capillary core is obtained by sintering aluminum powder with the thickness of 3 mm-5 mm.
In the water vapor area, the surface of the hydrophobic plate is provided with a plurality of concave structures.
Preferably, the diameter of the recessed features is less than 100 μm;
preferably, the recessed structure is obtained by chemically etching the hydrophobic plate.
The capillary core structure on the surface of the hydrophilic plate and the concave structure on the surface of the hydrophobic plate in the water vapor area cooperate with each other to assist water vapor double-phase circulation and heat transfer or blocking;
when heat is transferred to the hydrophobic plate from the hydrophilic plate, the liquid phase is heated and evaporated on one side of the hydrophilic plate, vapor is condensed on one side of the hydrophobic plate, and due to the super-hydrophobicity formed by the concave structure and the surface modification of the hydrophobic plate, liquid drops of the liquid phase cannot stay on the surface of the hydrophobic plate, roll back to one side of the hydrophilic plate and are absorbed by the capillary core on the surface of the hydrophilic plate, so that a forward heat transfer cycle is formed. The heat transfer coefficient of the forward circulation is 30W/mK-100W/mK;
when heat is transferred from the hydrophobic plate to the hydrophilic plate, the liquid phase is heated and evaporated at one side of the hydrophobic plate, steam is condensed at one side of the hydrophilic plate, liquid droplets of the liquid phase are absorbed by the capillary core due to the super-hydrophilicity of the capillary core on the surface of the hydrophilic plate, the liquid phase cannot overflow the capillary core based on the filling volume of the heat transfer working medium, the heat transfer circulation is blocked, and reverse heat transfer blocking is formed. The heat transfer coefficient is less than 0.5W/m.K when the reverse blocking is carried out, and the heat insulation capability is strong.
Preferably, the thermal conductivity of the seal is less than 0.5W/(m K);
preferably, the material of the sealing element comprises at least one of polytetrafluoroethylene, polypropylene, acrylic, phenolic resin, polyurethane and rubber;
more preferably, the sealing element is made of polytetrafluoroethylene;
for the sealing element, the stronger the heat insulation performance, the better the material effect, but the corresponding raw material cost will also rise, and the material of the sealing element is selected with the adaptability according to the application scenario and the economic cost.
Preferably, the heat transfer working medium is deionized water;
more preferably, the volume of the deionized water is no more than 40% of the volume of the capillary wick;
more preferably, the vacuum level of the moisture zone is less than 10 degrees f prior to filling with deionized water-3Pa；
Physical properties such as gas-liquid conversion temperature, heat capacity, surface tension and the like of the heat transfer working medium are closely related to the performance of the thermal diode, and water has high heat capacity, good surface tension, low cost and easy acquisition, thereby being an ideal heat transfer working medium of the thermal diode.
Meanwhile, the surface properties of the hydrophilic plate and the hydrophobic plate are matched with the physical properties of the heat transfer working medium to realize heat circulation. When deionized water is used as a heat transfer working medium, in a water vapor area, the contact angle of the deionized water on the surface of the hydrophilic plate is less than 10 degrees, the contact angle on the surface of the hydrophobic plate is more than 150 degrees, the rolling angle is less than 10 degrees, other gas and liquid do not exist in water and vapor in the water vapor area, and the heat transfer performance of the thermal diode can be affected by insufficient vacuum degree.
A preparation method of a flat thermal diode is adapted to the flat thermal diode and mainly comprises the following steps:
(1) sintering the hydrophilic plate with the aluminum powder on the surface to obtain a hydrophilic plate with a super-hydrophilic surface;
(2) carrying out electrochemical corrosion treatment on the hydrophobic plate, and then respectively modifying and treating the hydrophobic plate through a silver nitrate solution and a fluorosilane solution to obtain the hydrophobic plate with the super-hydrophobic surface;
(3) sequentially assembling the hydrophilic plate and the sealing member in the step (1) and the hydrophobic plate in the step (2), and carrying out fixing and sealing treatment to obtain the flat plate type thermal diode;
preferably, in the step (2), the silver nitrate solution is soaked for 2 to 3 hours, and the concentration of the silver nitrate solution is 3 to 7 weight percent;
preferably, in the step (2), the fluorosilane solution is soaked for 2 to 4 hours, and the concentration of the fluorosilane solution is 0.5 to 2 weight percent;
preferably, in step (2), the modification treatment further comprises: drying the hydrophobic plate at 100 ℃, wherein the drying time is 15-30 min; more preferably, the drying time is 20 min.
A solar heat collector comprises the flat thermal diode.
Compared with the prior art, the invention has the beneficial effects that:
(1) the flat plate type thermal diode has excellent unidirectional heat transfer capability and reverse heat insulation capability, controllable energy transfer direction and high heat transfer efficiency.
(2) The flat plate type thermal diode can adjust the whole appearance and the internal water vapor area cavity structure according to the use scene, and has high designability.
(3) The flat plate type thermal diode has the advantages of simple structure, short preparation method flow, less time consumption, suitability for mass production and better application prospect.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a schematic structural diagram of a planar thermal diode according to the present invention;
FIG. 2 is a schematic cross-sectional view of a planar thermal diode provided by the present invention;
FIG. 3 is a schematic view of a stage of the planar thermal diode provided by the present invention;
fig. 4 is a schematic structural diagram of a solar thermal collector provided by the present invention.
Detailed Description
The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and the detailed description, but those skilled in the art will understand that the following described embodiments are some, not all, of the embodiments of the present invention, and are only used for illustrating the present invention, and should not be construed as limiting the scope of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The invention proceeds from the following detailed description:
a flat thermal diode comprising a hydrophilic plate, a hydrophobic plate, and a seal disposed between the hydrophilic plate and the hydrophobic plate; at least one closed cavity formed among the hydrophilic plate, the hydrophobic plate and the sealing element is a water vapor area, and the water vapor area is used for bearing heat transfer working media;
and in the water vapor area, the surface of the hydrophilic plate is provided with a capillary core.
Fig. 1 is a schematic structural view of a planar thermal diode according to the present invention, and fig. 2 is a schematic cross-sectional view of the planar thermal diode according to the present invention.
In a preferred embodiment, the hydrophilic plate is made of aluminum alloy; in the water vapor area, the contact angle of water on the surface of the hydrophilic plate is less than 10 degrees.
In a preferred embodiment, the hydrophobic plate is also made of aluminum alloy; in the water vapor area, the contact angle of water on the surface of the hydrophobic plate is more than 150 degrees, and the rolling angle is less than 10 degrees.
In a preferred embodiment, the porosity of the capillary core is 45% to 55%, and the pore diameter of the capillary core is 50 μm to 150 μm; wherein the porosity of the wick includes, but is not limited to, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%; the pore size of the capillary wick includes, but is not limited to, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, 105 μm, 110 μm, 115 μm, 120 μm, 125 μm, 130 μm, 135 μm, 140 μm, 145 μm, 150 μm.
As a preferred embodiment, the capillary wick is obtained by sintering aluminum powder; specifically, a layer of aluminum powder is stacked on the surface of the hydrophilic plate and sintered to form the capillary core; the thickness of the aluminum powder is 3 mm-5 mm, including but not limited to 3mm, 4mm or 5 mm.
In a preferred embodiment, in the water vapor area, the surface of the hydrophobic plate is provided with a plurality of concave structures; the diameter of the concave structure is less than 100 μm; in a more preferred embodiment, the recessed structure is obtained by chemically etching the hydrophobic plate.
As a preferred embodiment, the thermal conductivity of the seal is less than 0.5W/(m × K); the sealing element is made of at least one of polytetrafluoroethylene, polypropylene, acrylic, phenolic resin, polyurethane and rubber;
as a preferred embodiment, the moisture region is planned by the configuration of the seal; obtaining a sealing element with a preset shape through mechanical processing and forming; specifically, the sealed cavity formed between the hydrophilic plate and the hydrophobic plate is divided into one or more regions by the sealing member, and the division of each region may be regular or irregular, and the specific division manner depends on the application of the thermal diode.
As a preferred embodiment, the heat transfer working medium is deionized water; the volume of the deionized water is no more than 40% of the capillary wick volume, including but not limited to 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%; the vacuum degree of the water vapor area is less than 10 before the deionized water is filled-3Pa。
In a preferred embodiment, a temperature measuring element is arranged in the hydrophilic plate and/or the hydrophobic plate; the temperature measuring element is used for inspecting the working performance of the thermal diode;
the temperature measuring element comprises any one of conventional temperature measuring elements such as a thermal resistor, a thermocouple, an infrared thermometer and the like; in a more preferred embodiment, the temperature measuring element is a thermocouple.
As a preferred embodiment, pre-embedded grooves are arranged inside the hydrophilic plate and the hydrophobic plate according to the shape of the temperature measuring element, and are used for placing the temperature measuring element; it should be noted that the depth of the pre-buried groove should be as close to the hydrophilic region as possible to ensure that the measured temperature is as close to the temperature inside the hydrophilic region as possible; the embedded grooves correspond to the temperature measuring elements one to one, and 2-4 embedded grooves are respectively formed in the hydrophilic plate and the hydrophobic plate.
A preparation method of a flat thermal diode mainly comprises the following steps:
(1) sintering the hydrophilic plate with the aluminum powder on the surface to obtain a hydrophilic plate with a super-hydrophilic surface;
(2) carrying out electrochemical corrosion treatment on the hydrophobic plate, and then respectively modifying and treating the hydrophobic plate through a silver nitrate solution and a fluorosilane solution to obtain the hydrophobic plate with the super-hydrophobic surface;
(3) sequentially assembling the hydrophilic plate and the sealing member in the step (1) and the hydrophobic plate in the step (2), and carrying out fixing and sealing treatment to obtain the flat plate type thermal diode;
as a preferred embodiment, in step (2): carrying out electrochemical corrosion treatment on the hydrophobic plate to obtain a plurality of pits with the diameter of less than 150 mu m, soaking the pits in a silver nitrate solution, taking out the pits and drying the pits, then modifying the surface of the hydrophobic plate by using a fluorosilane solution, and drying the pits at 80-120 ℃ to obtain the hydrophobic plate with the super-hydrophobic surface;
as a more preferable embodiment, the soaking treatment is performed for 2 to 3 hours in the step (2) by the silver nitrate solution, and the concentration of the silver nitrate solution is 3 to 7 wt%;
as a more preferable embodiment, in the step (2), the fluorosilane solution is soaked for 2 to 4 hours, and the concentration of the fluorosilane solution is 0.5 to 2 weight percent;
as a more preferable embodiment, in the step (2), after the modification treatment, the method further comprises: drying the hydrophobic plate at 100 ℃, wherein the drying time is 15-30 min; as a further preferred embodiment, the drying time is 20 min.
As a preferred embodiment, the preparation method further comprises: preparing a through hole on the hydrophilic plate or the hydrophobic plate for placing a liquid filling pipe; this operation adaptability is added to step (1) when a through hole is made on the hydrophilic plate, and to step (3) when a through hole is made on the hydrophobic plate;
the liquid filling pipe is used for extracting vacuum and filling heat transfer working media; and after the liquid filling is finished, removing the liquid filling pipe, and re-filling the hydrophilic plate or the hydrophobic plate. Figure 3 is a schematic view of a planar thermal diode provided by the present invention at this stage.
Fig. 4 is a schematic structural view of the solar thermal collector provided by the invention. The solar heat collector integrates heat collection, heat storage and heat extraction, and mainly comprises a heat collector, a flat thermal diode and a hot water storage device, wherein the hot water storage device comprises a cold water inlet and a hot water outlet.
The working principle of the solar heat collector mainly comprises the following steps: the solar radiation energy projected on the surface of the heat collector is absorbed by one side of a hydrophilic plate of the flat plate type thermal diode, and a liquid phase on one side of the hydrophilic plate is heated and evaporated and is gathered on one side of a hydrophobic plate; the hot water storage device is fixedly connected with one side of the hydrophobic plate, cold water is stored in the hot water storage device in advance, hot steam is liquefied at one side of the hydrophobic plate to release heat and transfers the heat to the hot water storage device, and liquid drops at one side of the hydrophobic plate flow back to one side of the hydrophilic plate to form circulation. After a period of time, the liquid in the hot water storage device is warmed to a suitable temperature.
While particular embodiments of the present invention have been illustrated and described, it will be appreciated that the above embodiments are merely illustrative of the technical solution of the present invention and are not restrictive thereof; those of ordinary skill in the art will understand that: modifications may be made to the above-described embodiments, or equivalents may be substituted for some or all of the features thereof without departing from the spirit and scope of the present invention; the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the present invention; it is therefore intended to cover in the appended claims all such alternatives and modifications that are within the scope of the invention.
Claims (10)
1. A flat thermal diode comprising a hydrophilic plate, a hydrophobic plate, and a seal disposed between the hydrophilic plate and the hydrophobic plate; at least one closed cavity formed among the hydrophilic plate, the hydrophobic plate and the sealing element is a water vapor area, and the water vapor area is used for bearing heat transfer working media;
and in the water vapor area, the surface of the hydrophilic plate is provided with a capillary core.
2. The planar thermal diode according to claim 1 wherein the hydrophilic plate is made of aluminum alloy;
preferably, in the water vapor region, the contact angle of water on the surface of the hydrophilic plate is less than 10 °.
3. The planar thermal diode according to claim 1, wherein the porosity of the wick is 45-55%, and the pore size of the wick is 50-150 μm;
preferably, the capillary wick is obtained by sintering aluminum powder;
more preferably, the capillary core is obtained by sintering aluminum powder with the thickness of 3 mm-5 mm.
4. The planar thermal diode according to claim 1 wherein the hydrophobic plate is made of aluminum alloy;
preferably, in the water vapor area, the contact angle of water on the surface of the hydrophobic plate is more than 150 degrees, and the rolling angle is less than 10 degrees.
5. The planar thermal diode according to claim 1 wherein the surface of the hydrophobic plate has a plurality of concave structures in the moisture region;
preferably, the diameter of the recessed features is less than 100 μm;
preferably, the recessed structure is obtained by chemically etching the hydrophobic plate.
6. The planar thermal diode of claim 1 wherein the thermal conductivity of the encapsulant is less than 0.5W/(m K);
preferably, the material of the sealing element includes at least one of polytetrafluoroethylene, polypropylene, acrylic, phenolic resin, polyurethane and rubber.
7. The planar thermal diode according to claim 1 wherein the heat transfer working medium is deionized water;
preferably, the volume of the deionized water is no more than 40% of the volume of the capillary wick;
preferably, the vacuum level of the moisture zone is less than 10 degrees f prior to filling with deionized water-3Pa。
8. The planar thermal diode according to any of claims 1 to 7 wherein a temperature measuring element is disposed within the hydrophilic and/or hydrophobic plate.
9. A method for preparing a flat thermal diode is characterized by mainly comprising the following steps:
(1) sintering the hydrophilic plate with the aluminum powder on the surface to obtain a hydrophilic plate with a super-hydrophilic surface;
(2) carrying out electrochemical corrosion treatment on the hydrophobic plate, and then respectively modifying the hydrophobic plate through silver nitrate solution and fluorosilane solution to obtain the hydrophobic plate with the super-hydrophobic surface;
(3) sequentially assembling the hydrophilic plate and the sealing member in the step (1) and the hydrophobic plate in the step (2), and carrying out fixing and sealing treatment to obtain the flat plate type thermal diode;
preferably, in the step (2), the silver nitrate solution is soaked for 2 to 3 hours, and the concentration of the silver nitrate solution is 3 to 7 weight percent;
preferably, in the step (2), the fluorosilane solution is soaked for 2 to 4 hours, and the concentration of the fluorosilane solution is 0.5 to 2 weight percent;
preferably, in step (2), the modification treatment further comprises: and drying the hydrophobic plate at 100 ℃, wherein the drying time is 15-30 min.
10. A solar thermal collector comprising a planar thermal diode according to any one of claims 1 to 8.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120012804A1 (en) * | 2009-04-21 | 2012-01-19 | Chuan-Hua Chen | Thermal diode device and methods |
| CN103469215A (en) * | 2013-09-06 | 2013-12-25 | 许昌学院 | Copper based super-hydrophobic surface with low friction coefficient and preparation method thereof |
| CN103687455A (en) * | 2013-12-31 | 2014-03-26 | 上海交通大学 | Vapor chamber |
| CN111486734A (en) * | 2020-04-01 | 2020-08-04 | 浙江理工大学 | Vapor chamber and manufacturing method thereof |
| WO2021263114A2 (en) * | 2020-06-25 | 2021-12-30 | Virginia Polytechnic Institute And State University | Planar bridging-droplet thermal diode |
-
2022
- 2022-02-21 CN CN202210156312.6A patent/CN114526623A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120012804A1 (en) * | 2009-04-21 | 2012-01-19 | Chuan-Hua Chen | Thermal diode device and methods |
| CN103469215A (en) * | 2013-09-06 | 2013-12-25 | 许昌学院 | Copper based super-hydrophobic surface with low friction coefficient and preparation method thereof |
| CN103687455A (en) * | 2013-12-31 | 2014-03-26 | 上海交通大学 | Vapor chamber |
| CN111486734A (en) * | 2020-04-01 | 2020-08-04 | 浙江理工大学 | Vapor chamber and manufacturing method thereof |
| WO2021263114A2 (en) * | 2020-06-25 | 2021-12-30 | Virginia Polytechnic Institute And State University | Planar bridging-droplet thermal diode |
Non-Patent Citations (3)
| Title |
|---|
| 刘腾庆等: "强化平板热管传热性能的研究进展", 化工学报, vol. 72, no. 11, pages 5468 - 5480 * |
| 苗建印等: "航天器热控制技术", 31 March 2018, 北京理工大学出版社, pages: 115 * |
| 陶素连: "热柱符合毛细芯成形机理及性能研究", 29 February 2020, 华南理工大学出版社, pages: 11 * |
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