Radiation cooling cover plate, external melt ice thermal energy storage tank with passive ice making including the cover plate, and air conditioning system

Abstract

The present invention discloses a radiation cooling cover plate for an external melt ice storage tank for passive ice making, an ice storage tank including the radiation cooling cover plate, and an air conditioning system. The radiation cooling cover plate includes: a copper substrate (1-6); an aluminum layer (1-5) above the copper substrate (1-6); an amorphous silicon layer (1-4) above the aluminum layer (1-5); a Si3N4 coating (1-3) above the amorphous silicon layer (1-4); a support frame (1-2) above the Si3N4 coating (1-3), and a ZnSe window plate (1-1) disposed on the top of the support frame (1-2), wherein the Si3N4 coating (1-3), the support frame (1-2), and the ZnSe window plate (1-1) form a sealed vacuum chamber.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and particularly to a radiation cooling cover plate, an external-melting ice thermal energy storage tank for passive ice making including the cover plate, and an air conditioning system. Background Art

[0002] Thermal energy storage technology is one of the important means to reduce the installed capacity of air conditioning systems and the air conditioning power load during peak grid hours at present. However, the existing thermal energy storage technology only plays the role of "peak shaving and valley filling", and actually does not save electricity or reduce energy consumption.

[0003] Therefore, new technologies and equipment are needed to at least partially eliminate the problems existing in the prior art. For example, it can reduce the ice-making energy consumption of air conditioning systems, reduce carbon emissions, and promote the cause of carbon peak before 2030 and carbon neutrality before 2060. Summary of the Invention

[0004] The purpose of the present invention is to reduce the ice-making and ice-storing energy consumption of air conditioning systems, and provides an external-melting ice thermal energy storage tank for passive ice making and its coupling application method in an air conditioning system. The thermal energy storage tank can emit infrared rays to outer space through radiation heat transfer to reduce its own temperature, and transfer the cold energy to the internal medium of the thermal energy storage tank for storage, so as to achieve the purpose of reducing the ice-making and ice-storing energy consumption of air conditioning systems, and saving energy and reducing emissions.

[0005] More specifically, according to one aspect of the present invention, there is provided a radiation cooling cover plate (1) for an external-melting ice thermal energy storage tank for passive ice making, which is characterized by including

[0006] A copper substrate (1-6);

[0007] An aluminum layer (1-5) on the copper substrate (1-6);

[0008] An amorphous silicon layer (1-4) on the aluminum layer (1-5);

[0009] A Si3N4 coating (1-3) on the amorphous silicon layer (1-4);

[0010] A support frame (1-2) on the Si3N4 coating (1-3), and

[0011] A ZnSe window sheet (1-1) provided on the top of the support frame (1-2), wherein the Si3N4 coating (1-3), the support frame (1-2) and the ZnSe window sheet (1-1) form a sealed vacuum chamber.

[0012] According to an embodiment of the present invention, the thickness of the copper substrate (1-6) is 0.5-5 mm, preferably 1-2 mm; the thickness of the amorphous silicon layer (1-4) is 500 nm-1000 nm, preferably 650-750 nm.

[0013] According to an embodiment of the present invention, the thickness of the aluminum layer (1-5) is 100 nm-300 nm, preferably 130-160 nm.

[0014] According to an embodiment of the present invention, the thickness of the Si3N4 coating is 50-100 nm, preferably 60-75 nm.

[0015] According to an embodiment of the present invention, the thickness of the ZnSe window plate (1-1) is 2-5 mm.

[0016] According to an embodiment of the present invention, the emissivity of the radiation cooling cover plate in the atmospheric window is 0.8-0.95, and the reflectivity in the solar light band is 0.85-0.95.

[0017] According to an embodiment of the present invention, the pressure of the vacuum chamber is 10 -6 mm of mercury or less.

[0018] According to another aspect of the present invention, there is provided an external-melt ice storage tank for passive ice making, including the radiation cooling cover plate according to the present invention.

[0019] According to an embodiment of the present invention, the ice storage tank further includes an ice storage tank housing (8) with an open top and a heat exchange coil (11) disposed inside the housing (8). The radiation cooling cover plate (1) seals the open top of the housing (8) and contacts the top of the heat exchange coil (11).

[0020] According to another aspect of the present invention, there is provided an air conditioning system including the ice storage tank according to the present invention.

[0021] The present invention utilizes the method of passive radiative heat transfer. By exciting surface phonons of the Si3N4 material, the emissivity in the atmospheric window is increased, thereby enhancing the radiative heat transfer to outer space. By utilizing the high transmittance of the ZnSe window plate in the infrared band, the high reflectance of aluminum in the sunlight band, and the heat insulation effect of the vacuum layer, the absorption of sunlight by the cover plate and non-radiative heat transfer are greatly reduced, ultimately achieving the effect of passive cooling. The net radiative heat transfer power of the ice storage tank (the power radiated outwards minus the power of external heat input) is between 0 - 100 W / ㎡, and the maximum temperature drop can reach about 42 °C lower than the ambient temperature. In addition, the ice storage tank continuously radiates heat to outer space day and night, and can also achieve the ice-making effect during the day. The emissivity of the radiative cooling cover plate of the present invention in the atmospheric window (8 - 13 microns) can reach 0.8 - 0.95, and the reflectivity in the sunlight band (0.3 - 2.5 microns) can reach 0.85 - 0.95, such as about 0.9.

[0022] The external-melt ice storage tank for passive ice making and the air conditioning system of the present invention are an effective means to reduce the ice-making energy consumption of the air conditioning system and indirectly reduce carbon emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The features of the present application can be better understood with reference to the drawings and claims described below. The drawings are not necessarily drawn to scale, but generally focus on illustrating the principles described herein. In the drawings, like numerals are used to indicate like parts throughout the views.

[0024] Figure 1 is a cross-sectional schematic view of the structure of an external-melt ice storage tank for passive ice making according to an embodiment of the present application.

[0025] Figure 2 is Figure 1 a top view schematic of the structure of the external-melt ice storage tank for passive ice making shown.

[0026] Figure 3 is a schematic structural view of a radiative cooling cover plate for an external-melt ice storage tank for passive ice making according to an embodiment of the present application.

[0027] Figure 4 is a schematic diagram of the coupled application of an external-melt ice storage tank for passive ice making in an air conditioning system according to an embodiment of the present application.

[0028] Wherein: 1 radiative cooling cover plate, 1-1 ZnSe window plate, 1-2 support frame, 1-3 Si3N4 coating, 1-4 amorphous silicon layer, 1-5 aluminum layer, 1-6 copper substrate, 2 refrigerant inlet pipe, 3 refrigerant outlet pipe, 4 inlet water distributor, 5 outlet water distributor, 6 coolant inlet pipe, 7 coolant outlet pipe, 8 outer shell, 9 thermal insulation material, 10 internal support, 11 heat exchange coil, 12, liquid distributor, 13 liquid collector. Detailed implementation manners

[0029] The present invention will be further described below in conjunction with the accompanying drawings and embodiments, and the content mentioned is not used to limit the present invention.

[0030] Figure 1 and Figure 2 are a cross-sectional view and a top view schematic diagram of an external-melting ice storage tank structure for passive ice making according to an embodiment of the present application. Figure 3 is a schematic structural diagram of a radiation cooling cover plate of an external-melting ice storage tank for passive ice making according to an embodiment of the present application.

[0031] Referring to Figure 3 , the radiation cooling cover plate 1 of this embodiment may include a copper substrate 1-6, an aluminum layer 1-5 on the copper substrate 1-6, an amorphous silicon layer 1-4 on the aluminum layer 1-5, a Si3N4 coating 1-3 on the amorphous silicon layer 1-4, a support frame 1-2 on the Si3N4 coating 1-3, and a ZnSe window sheet 1-1 provided on the top of the support frame 1-2.

[0032] The radiation cooling cover plate is made as follows: Copper with a thickness of 0.5-5 mm, preferably 1-2 mm, is used as the copper substrate 1-6, and an aluminum layer 1-5 with a thickness of 100 nm - 300 nm, preferably 130 - 160 nm, is tightly connected to the copper substrate 1-6 through thermal conductive silicone or other suitable adhesives to play a role in reflecting solar radiation; an amorphous silicon layer 1-4 with a thickness of 500 nm - 1000 nm, preferably 650 - 750 nm, is laid on the aluminum layer 1-5. Since the amorphous silicon layer 1-4 and the aluminum layer 1-5 have smooth and flat surfaces, the amorphous silicon layer 1-4 can be placed on the aluminum layer 1-5 and pressed to make them in close contact, so that the aluminum layer 1-5 and the amorphous silicon layer 1-4 can be tightly connected through intermolecular forces.

[0033] Then, the Si3N4 solution is evenly sprayed on the amorphous silicon 1-4 at a high temperature by using a spraying device, and the thickness of the Si3N4 coating 1-3 is controlled between 50 - 100 nm by increasing the spraying times, and it is left to dry at room temperature. More specifically, distilled water can be used as a solvent to dissolve Si3N4, and the volume ratio of distilled water to Si3N4 is between 10:1 and 10:3; the Si3N4 solution is sprayed on the amorphous silicon 1-4 at a high temperature, and the thickness of the Si3N4 coating is controlled between 60 - 75 nm by the spraying times, and it is left to dry at room temperature.

[0034] After it is fully dried, a ZnSe window sheet 1-1 with a thickness of about 2-5 mm is covered above the Si3N4 coating 1-3 and supported by a support frame 1-2. The support frame can be made of acrylic material, for example, or other suitable materials. The Si3N4 coating 1-3, the support frame 1-2, and the ZnSe window sheet 1-1 form a sealed cavity, and the spacing between the ZnSe window sheet 1-1 and the Si3N4 coating 1-3 can be 0.5-1 cm, for example. Then, the cavity can be evacuated with a vacuum pump, for example, reducing the pressure therein to about 10 -6 mm Hg or lower. The phonon excitation on the surface of the Si3N4 coating can increase its emissivity in the atmospheric window, thereby enhancing the radiative heat transfer to outer space. The aluminum layer can reflect sunlight, and the vacuum cavity plays a heat insulation role. Finally, by radiating heat to outer space, the absorption of solar radiation and non-radiative heat transfer is weakened, thereby achieving a cooling effect. The emissivity of the radiative cooling cover plate 1 of the present invention in the atmospheric window (8-13 microns) can be 0.8-0.95, for example, and the reflectivity in the sunlight band (0.3-2.5 microns) can be 0.85-0.95, for example, about 0.9.

[0035] Reference Figure 1 and Figure 2 According to

[0036] the passive ice-making external-melting ice storage tank of the present embodiment may include a radiative cooling cover plate 1, a refrigerant inlet pipe 2, a refrigerant outlet pipe 3, an inlet water distributor 4, an outlet water distributor 5, a secondary coolant inlet pipe 6, a secondary coolant outlet pipe 7, a housing 8, a thermal insulation material 9, an internal support 10, a heat exchange coil 11, a liquid distributor 12, and a liquid collector 13.

[0037] In the embodiments of the present invention, the radiation cooling cover plate is closely connected to the heat exchange coil to prevent the generation of contact thermal resistance. The larger the contact area between the two, the better the heat exchange and refrigeration effect. The radiation cooling cover plate of the present invention itself has a high infrared emissivity, which can emit heat in the form of infrared rays through the atmospheric window of 8-13 microns to the outer space with a temperature of only 3K (minus 270 °C), thereby reducing its own temperature. Its high emissivity can be achieved by phonon excitation on the surface of a Si3N4 coating with a certain thickness, and the thickness and adhesion of the Si3N4 coating can be controlled by the number of spraying times, spraying distance, spraying pressure, etc., so that it finally has a high infrared emissivity.

[0038] Reference Figure 4 , the passive ice-on-coil ice storage tank of the present invention can be applied to an air conditioning system. The following specifically describes the coupling application method of the passive ice-on-coil ice storage tank of the present invention in the air conditioning system.

[0039] First, connect the refrigerant inlet pipe 2 of the above-mentioned ice storage tank to the refrigerant outlet b of the air conditioning system and set a valve V1; connect the refrigerant outlet pipe 3 to the inlet a of the air conditioning system and set a valve V2.

[0040] Second: Connect the coolant inlet pipe 6 to the load side outlet d and set a valve V3; connect the coolant outlet pipe 7 to the load side inlet c and set a valve V4; set a valve V5 in the b-c pipe section.

[0041] Third step: By adjusting the opening and closing of the valves, different operating conditions can be achieved, specifically as follows:

[0042] Ice making condition

[0043] When the ice storage capacity of the passive ice-on-coil ice storage tank is insufficient, valves V1 and V2 can be opened, and V3, V4, and V5 can be closed. The air conditioning system supplements the insufficient ice making load.

[0044] Cooling release condition

[0045] When it is necessary to release the stored cold energy, open valves V3 and V4, and close V1, V2, and V5. The stored cold energy undertakes the load.

[0046] Combined operation condition

[0047] When it is necessary for both to work simultaneously, open valves V3, V4, and V5, and close V1 and V2, so that the ice storage tank and the air conditioning unit are in parallel to jointly undertake the load.

[0048] It should be understood that the variations or their alternatives of the above-disclosed features and functions, as well as others, can be combined into many other different systems or applications. Those skilled in the art can subsequently make various currently unforeseen or unforeseeable substitutions, modifications, variations or improvements, and these substitutions, modifications, variations or improvements are also intended to be covered by the appended claims.

Claims

1. A radiation cooling cover plate (1) for an external melt ice thermal energy storage tank used for passive ice making, characterized in that, including a copper substrate (1-6); an aluminum layer (1-5) on the copper substrate (1-6); an amorphous silicon layer (1-4) on the aluminum layer (1-5); a Si3N4 coating (1-3) on the amorphous silicon layer (1-4); a support frame (1-2) on the Si3N4 coating (1-3), and a ZnSe window pane (1-1) disposed on top of the support frame (1-2), wherein the Si3N4 coating (1-3), the support frame (1-2) and the ZnSe window pane (1-1) form a sealed vacuum chamber.

2. The radiation cooling cover plate (1) according to claim 1, characterized in that, The thickness of the copper substrate (1-6) is 0.5 - 5 mm; the thickness of the amorphous silicon layer (1-4) is 500 nm - 1000 nm.

3. The radiation cooling cover plate (1) according to claim 1, characterized in that, The thickness of the aluminum layer (1-5) is 100 nm - 300 nm.

4. The radiative cooling cover plate (1) according to claim 1, characterized in that, The thickness of the Si3N4 coating is 50 - 100 nm.

5. The radiation cooling cover plate (1) according to claim 1, characterized in that, The thickness of the ZnSe window pane (1-1) is 2 - 5 mm.

6. The radiative cooling cover plate (1) according to claim 1, characterized in that, The emissivity of the radiation cooling cover plate in the atmospheric window is 0.8 - 0.95, and the reflectivity in the solar light band is 0.85 - 0.

95.

7. The radiation cooling cover plate (1) according to claim 1, characterized in that, The pressure in the vacuum chamber is 10 -6 mmHg or less.

8. The radiative cooling cover plate (1) according to claim 1, characterized in that, The thickness of the copper substrate (1-6) is 1 - 2 mm; the thickness of the amorphous silicon layer (1-4) is 650 - 750 nm.

9. The radiation cooling cover plate (1) according to claim 1, characterized in that, The thickness of the aluminum layer (1-5) is 130 - 160 nm.

10. The radiation cooling cover plate (1) according to claim 1, characterized in that, The thickness of the Si3N4 coating is 60 - 75 nm.

11. An external-melt ice storage tank for passive ice making, characterized in that, including the radiation cooling cover plate (1) according to any one of claims 1-10.

12. The ice storage tank according to claim 11, wherein, Further including an ice storage tank housing (8) with an open top and a heat exchange coil (11) disposed inside the housing (8), the radiation cooling cover plate (1) covering the top opening of the housing (8) and contacting the top of the heat exchange coil (11).

13. An air conditioning system, characterized in that, including the ice storage tank according to any one of claims 11-12.

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