Dual-temperature self-adaptive building cooling energy-saving device based on passive radiation cooling

Abstract

The invention discloses a dual-temperature self-adaptive building cooling energy-saving device based on passive radiation cooling. The device is composed of an outdoor straight pipe coated with a self-adaptive passive radiation refrigeration coating, an indoor top coil pipe used for heat exchange, a top liquid storage tank, a bottom liquid storage tank, an electromagnetic valve and a temperature sensor which are connected with a central controller, and a pipeline system connected with the electromagnetic valve and the temperature sensor. The working fluid is introduced into the indoor top for direct heat exchange, the heat exchange efficiency is higher, meanwhile, the working state can be automatically adjusted according to the self-modulation effect of the self-adaptive passive radiation refrigeration coating and the difference between indoor and outdoor temperatures and the set temperature, the building is prevented from being too cold, and therefore energy is saved for the building all the year round; the device has the advantages of being energy-saving, environment-friendly, simple in operation and structure, wide in application range and the like, and is particularly suitable for buildings or devices with high internal heat productivity, such as machine rooms, boiler rooms, steelmaking workshops, power transformation boxes and the like.

Description

Technical Field

[0001] The invention relates to the field of building energy conservation, and in particular to a dual temperature self-adaptive building cooling and energy-saving device based on passive radiation cooling. Background Art

[0002] At present, air conditioning equipment is mostly used for building cooling. People's growing demand for thermal comfort has driven up energy consumption for cooling and huge carbon emissions, exacerbating global warming. In particular, buildings such as machine rooms and cold storages require long-term use of refrigeration machines for cooling, which consumes a lot of energy. The development of building cooling and energy-saving devices is in line with the development trend of achieving "carbon emission reduction".

[0003] Passive radiation cooling technology is a green zero-energy refrigeration technology that has emerged in recent years. It achieves spontaneous cooling through the following mechanisms: high reflection of sunlight in all bands; high infrared emission in the atmospheric window band. Using passive radiation cooling technology to cool buildings is an important means of energy conservation and environmental protection. At the same time, the adjustable passive radiation cooling technology can realize the opening and closing of the refrigeration function, so that it can be applied to more occasions. Summary of the invention

[0004] The present invention aims to propose a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling, which is suitable for various types of buildings and can achieve indoor cooling of low-energy buildings.

[0005] The technical solution adopted by the present invention is as follows: a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling, which is composed of an outdoor straight tube coated with an adaptive passive radiation cooling coating, an indoor top coil for heat exchange, a top liquid storage tank, a bottom liquid storage tank, a solenoid valve connected to a central controller and a temperature sensor, and a connected pipeline system. A plurality of multi-section straight tubes are regularly and densely arranged on the outdoor top of the building and the sunny walls of each floor, and each section of the single straight tube is connected. The straight tube is installed with an outdoor temperature sensor, and the upper end of the straight tube is connected to the inlet and outlet of the indoor top coil through two three-way joints. A straight tube solenoid valve is installed between the two three-way joints, and the three-way joint is a polymer plastic pipe with a low thermal conductivity coefficient. An indoor temperature sensor and a coil solenoid valve are installed on the indoor top coil. The bottom of the outdoor vertical straight pipe is connected to the manifold, which is connected to a connection port of the liquid pump in the bottom liquid storage tank, and the other connection port of the liquid pump is connected to the return pipe. The return pipe is equipped with a return pipe solenoid valve, and the other end of the return pipe is connected to the liquid storage tank at the top of the building. A liquid level meter is installed on the top liquid storage tank, and a liquid replenishment solenoid valve is installed at each outlet to communicate with the outdoor top straight pipe. The liquid level meter installed on it can monitor the liquid level in the top liquid storage tank. The outer side of the multiple straight pipes on the top and each layer of the sunny wall and the surface of the top liquid storage tank are coated with an adaptive passive radiation cooling coating. The formula, coating area and thickness of the adaptive passive radiation cooling coating, and the number of cooling straight pipes can be configured according to regional, climate and other characteristics.

[0006] The present invention discloses a dual temperature self-adaptive building cooling and energy-saving device based on passive radiation cooling. A spoiler element can be installed in the pipeline to enhance heat exchange, and a protective device can be installed outside the outdoor straight pipe to extend the service life of the self-adaptive passive radiation cooling coating.

[0007] Furthermore, the adaptive passive radiation cooling coating has a thermochromic radiation cooling coating. It is mainly composed of a polymer substrate (TPU, PVDF, PMMA, etc.), inorganic particles (ZrO2, SiO2, BaSO4, etc.), a phase change metal material (VO2), etc., and has a multi-level micro-nano structure such as pores, particles, and fibers. When the ambient temperature is high, the adaptive passive radiation cooling coating has a high solar reflectivity and a high emissivity in the mid-infrared band; when the ambient temperature is low, the adaptive passive radiation cooling coating has a low solar reflectivity and a low mid-infrared band emissivity, and the passive radiation cooling capacity is reduced to avoid indoor overcooling of the building; the first adaptive temperature regulation is achieved through the self-modulation function of the adaptive passive radiation cooling coating. At the same time, the above-mentioned adaptive passive radiation cooling coating can have functions such as super hydrophobicity, self-cleaning, and anti-light aging.

[0008] Furthermore, each solenoid valve is installed on the outdoor pipeline and connected to the central controller. The indoor and outdoor temperature sensors are connected to the central controller, and the central controller collects data from the indoor and outdoor temperature sensors. The indoor temperature sensor collects the real-time indoor temperature, and the outdoor temperature sensor collects the working fluid temperature in the vertical pipe. By comparing the temperature data collected by the temperature sensors in the indoor and outdoor pipelines with the preset temperature of the system, the opening and closing of the solenoid valves at different positions in the pipeline can be controlled to achieve the management of the opening and closing of the passive radiation cooling effect of the building. The second adaptive temperature adjustment is achieved by the central controller. When the temperature data of the indoor temperature sensor is higher than the preset temperature of the central controller, the coil solenoid valve, the return pipe solenoid valve and the liquid replenishment solenoid valve connected to the top liquid storage tank are opened, and the straight pipe solenoid valve between the three-way joints of the outdoor pipeline is closed. The working fluid circulates to work under the action of the adaptive passive radiation cooling coating to achieve building cooling; if the temperature data of the indoor temperature sensor is lower than the temperature data of the outdoor temperature sensor or the required indoor set temperature, the indoor top coil solenoid valve is closed, and the fluid in the pipe no longer flows. If the device is not needed for a long time, the indoor top coil solenoid valve is closed, the liquid replenishment solenoid valve at the outlet of the building top storage tank is closed and the working fluid is no longer replenished, and the outdoor straight pipe solenoid valve is opened to discharge the working fluid into the bottom storage tank, and the fluid in the pipe is emptied to prevent heat dissipation.

[0009] Furthermore, the liquid storage tank on the top of the building can be connected to the building water supply pipeline, and the working fluid can be directly replenished when it is water; when the working fluid is a refrigerant, nanofluid, etc., it can be directly added to the liquid storage tank on the top of the building. When the straight pipe coated with the adaptive passive radiation cooling coating lacks working fluid, the liquid replenishment solenoid valve at the outlet of the liquid storage tank on the top of the building is opened to replenish the working fluid; in cold areas, in order to avoid long-term refrigeration without the need for refrigeration, the working fluid freezes and solidifies to damage the pipeline system, and the working fluid can be discharged in time. The outdoor straight pipe solenoid valves are all opened to discharge the working fluid to the liquid storage tank at the bottom of the building. The bottom liquid storage tank has an insulation layer; when the working fluid is required to work continuously in the straight pipe coated with the adaptive passive radiation cooling coating and the indoor top coil, the coil solenoid valve, the return pipe solenoid valve and the liquid replenishment solenoid valve are opened, and the straight pipe solenoid valve between the outdoor pipeline three-way joints is closed to achieve the circulation of the fluid under working conditions.

[0010] Furthermore, the working fluid includes but is not limited to water, refrigerant, nanofluid, and mixtures thereof, and can be added to the pipeline system as needed when supplementing the working fluid. The circulation of the working fluid can be achieved through thermal convection, gas-liquid flow, pumping, and pipeline microchannel directional water delivery structure, but is not limited to the above design. When the building is cooled, the working fluid in the straight pipe naturally flows downward under the action of the adaptive passive radiation cooling coating, and the working fluid enters the indoor top coil through the three-way interface. After sufficient heat exchange with the indoor air, it flows into the lower pipeline of the building under the action of natural convection to cool down again. The above process is repeated until it enters the liquid storage tank at the bottom of the building. The working fluid enters the top liquid storage tank through the return pipe under the action of pumping, and the replenishment solenoid valve connected to the top liquid storage tank opens, and the working fluid enters the outdoor pipeline to complete the refrigeration cycle.

[0011] Furthermore, in order to ensure that the indoor top coil is filled with working fluid when it is in working state, and at the same time enable the working fluid to not only obtain more cooling outdoors but also fully exchange heat in the indoor top coil, the inner diameter of the outdoor straight pipe is 1.2 to 2.2 times the inner diameter of the indoor top coil.

[0012] Furthermore, when cooling the building through a refrigeration cycle, in order to ensure continuous flow of the working fluid and sufficient heat exchange, the inner diameter of the outdoor straight pipe may be 18 to 40 mm.

[0013] Furthermore, to enhance the heat exchange performance, the indoor top coil can use high thermal conductivity metal pipes, such as aluminum pipes, copper pipes, etc., or polymer plastic pipes filled with high thermal conductivity materials. Taking into account the heat exchange effect and the influence of ambient temperature, outdoor straight pipes can use metal pipes with different thermal conductivities or polymer plastic pipes filled with high thermal conductivity materials according to demand. The wall thickness of both can be selected from 2 to 10 mm according to the pipe diameter.

[0014] Furthermore, the indoor and outdoor temperature sensors required for each floor of the building can be installed individually or in multiples according to needs. If each floor uses one indoor temperature sensor and one outdoor temperature sensor, they can be arranged in the top coils of each floor of the building and in symmetrical positions in the middle of multiple straight pipes to measure the temperature; if multiple sensors are set up, they can be evenly distributed on multiple pipelines to measure the average temperature, which is finally input into the central controller.

[0015] Furthermore, the pipeline is fixed to the building wall by a water pipe fixing clamp, and a retractable protective cover is installed on the surface of the straight pipe. The retractable protective cover can be moved up and down by a motor-driven ball screw slide rail under the control of a central controller to cover the surface of the straight pipe or retract and store at the bottom of the straight pipe, thereby realizing the protection of the adaptive passive radiation cooling coating on the pipe wall in severe weather.

[0016] Furthermore, a spoiler element may be installed in the straight tube, and the spoiler element includes but is not limited to a combined rotor, a spiral bond, etc. The spoiler element rotates spontaneously under force when the working fluid flows, so that the heat transfer of the working fluid in the rotatable tube is more uniform and scaling is prevented in the tube, thereby enhancing the cooling effect and extending the working life.

[0017] Furthermore, a fin structure may be added to the indoor top coil to improve the heat exchange efficiency between the fluid in the tube and the indoor air.

[0018] Furthermore, the three-way joint polymer plastic pipe fitting can be prepared by injection molding and foaming, etc., and has an extremely low thermal conductivity, thereby avoiding direct heat exchange between indoor and outdoor air through the pipe wall and reducing parasitic heat of the system.

[0019] Furthermore, the energy consumption of the device is preferably powered by solar panels, and can also be connected to the building power supply system.

[0020] Compared with the prior art, the technical solution of the present application has the following beneficial technical effects: the adaptive building energy-saving and cooling device can effectively cool down the interior of the building through passive radiation cooling technology, and directly exchange heat by introducing the working fluid into the indoor ceiling, so that the heat exchange efficiency is higher. At the same time, the device can automatically adjust the working state according to the self-modulation effect of the adaptive passive radiation cooling coating and the difference between the indoor and outdoor temperatures and the set temperature to avoid overcooling of the building, thereby saving energy for the building throughout the year. It has the advantages of energy saving and environmental protection, simple operation and structure, and a wide range of applications, and has high application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the piping layout of a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling of the present invention; (a) axial schematic diagram of the piping layout, (b) microstructure diagram of the adaptive passive radiation cooling coating, (c) partial enlarged diagram of the indoor and outdoor piping connection, (d) left view of the piping layout.

[0022] Figure 2 This is a schematic diagram of the connection and fixing structure of a straight pipe and a protective cover of a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling of the present invention, (a) the protective cover is extended, and (b) the protective cover is retracted.

[0023] Figure 3 The present invention is a control principle diagram of an adaptive building energy-saving temperature control system of a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling.

[0024] Figure 4 This is a schematic diagram of a spoiler element installed in a straight pipe of a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling according to the present invention.

[0025] In the accompanying drawings, the list of components represented by each reference numeral is as follows: 1-adaptive passive radiation cooling coating, 2-straight pipe, 3-three-way connector, 4-outdoor temperature sensor, 5-top coil, 6-straight pipe solenoid valve, 7-coil solenoid valve, 8-indoor temperature sensor, 9-collecting pipe, 10-bottom liquid storage tank, 11-liquid pump, 12-return pipe, 13-return pipe solenoid valve, 14-top liquid storage tank, 15-liquid level gauge, 16-liquid replenishment solenoid valve, 17-water pipe fixing clamp, 18-motor, 19-protective cover, 20-ball screw slide, 21-central controller, 22-spoiler element. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The purpose of the present invention is to provide a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling, which is suitable for various types of buildings and can achieve indoor cooling of low-energy buildings to save energy and reduce emissions.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] like Figure 1As shown in (a)-(d), this embodiment provides a dual temperature adaptive building cooling and energy-saving device based on passive radiation cooling, which consists of an outdoor straight pipe 2 coated with an adaptive passive radiation cooling coating 1, an indoor top coil 5 for heat exchange, a top liquid storage tank 14 and a bottom liquid storage tank 10 for storing working fluid, a plurality of solenoid valves and a plurality of temperature sensors connected to a central controller 21, and a connected pipeline system. At the same time, a spoiler element 22 can be installed in the pipeline to enhance heat exchange, and a protective device can be installed outside the outdoor pipeline to extend the service life of the adaptive passive radiation cooling coating 1. Specifically, multiple straight pipes 2 coated with an adaptive passive radiation cooling coating 1 are regularly and densely arranged on the top of the outdoor building and the sunny walls of each floor, and the single straight pipes 2 of each section are connected through three-way joints 3. The straight pipes 2 of each floor of the building are installed with outdoor temperature sensors 4, and the upper ends of the straight pipes 2 are connected to the inlet and outlet of the indoor top coil 5 through two three-way joints 3. A straight pipe solenoid valve 6 is installed between the two three-way joints 3, and the three-way joints 3 are polymer plastic pipes with low thermal conductivity. The indoor top coil 5 is installed with a coil solenoid valve 7 and an indoor temperature sensor 8. The bottom of the outdoor straight pipe 2 is connected to a header 9, which is connected to a connection port of a liquid pump 11 in a bottom liquid storage tank 10, and another connection port of the liquid pump 11 is connected to a return pipe 12, on which a return pipe solenoid valve 13 is installed, and the other end of the return pipe 12 is connected to a liquid storage tank 14 at the top of the building, and a liquid level meter 15 is installed on the top liquid storage tank 14, and at each outlet thereof, a liquid replenishment solenoid valve 16 is installed to communicate with the outdoor top straight pipe 2, and at the same time, the top liquid storage tank 14 can be connected to the water supply pipeline of the building. The adaptive passive radiation cooling coating 1 has a temperature adaptive adjustment function, and the formula, coating area and thickness of the adaptive passive radiation cooling coating 1 and the number of straight pipes 2 can be configured according to regional, climate and other characteristics. A water pipe fixing clamp 17 is installed on the building wall and the indoor top pipeline, and a retractable protective cover 19 is installed on the surface of the straight pipe 2. The retractable protective cover 19 can move up and down along the ball screw guide rail 20 under the drive of the motor 18, and can cover the surface of the straight pipe 2 or shrink to store the bottom under the control of the central controller 21. Figure 2 (a) and Figure 2 (b) A flow-disturbing element 22 may be installed in the straight pipe 2, such as Figure 4 The flow-disturbing element 22 includes but is not limited to a spiral belt, a combined rotor, etc. The cooling device controls the electromagnetic valves of each pipeline and the liquid pump 11 to provide instructions for automatic operation through the temperature data collected by the central controller 21.

[0030] The specific implementation example of the present invention is Figure 3As shown: the system completes temperature adaptive building cooling under the dual effects of the adaptive passive radiation cooling coating 1 and the central controller 21. When in use, there is no working fluid inside the pipeline in the initial state. According to the selection of the working fluid, when the working fluid adopts building water supply, the building water supply is directly transported into the top liquid storage tank 14, and the liquid replenishment solenoid valve 16 is opened to replenish the working fluid; when the working fluid adopts refrigerant, nanofluid, etc., it can be configured to be added to the top liquid storage tank 14 as needed, and the liquid replenishment solenoid valve 16 at the outlet of the top liquid storage tank 14 is opened to replenish the working fluid.

[0031] When cooling the building, the outdoor temperature is higher than the phase change temperature of the phase change metal material with thermochromic characteristics in the adaptive passive radiation cooling coating 1, and the adaptive passive radiation cooling coating 1 has a high solar reflectivity and a high emissivity in the mid-infrared band, and the adaptive passive radiation cooling coating 1 starts the passive radiation cooling function. When the temperature data of the indoor temperature sensor 8 is higher than the preset temperature of the device, the working fluid in the straight pipe 2 flows downward naturally after cooling down under the passive radiation cooling function of the adaptive passive radiation cooling coating 1. At this time, the straight pipe solenoid valve 6 between the two three-way joints 3 of the outdoor pipeline is closed, and the working fluid enters the indoor top coil 5 through the three-way interface, and after sufficient heat exchange with the indoor air, it flows into the lower straight pipe 2 of the building under the action of natural convection to cool down again, and the above process is repeated until it enters the bottom liquid storage tank 10 of the building. The working fluid enters the top liquid storage tank 14 from the return pipe 12 under the pumping action of the liquid pump 11. At this time, the return pipe solenoid valve 13 is in an open state, and the top liquid storage tank 14 is connected to the outdoor pipeline. The replenishment solenoid valve 16 is opened, and the working fluid enters the outdoor pipeline for cooling again, and the refrigeration cycle is performed. If the temperature data of the indoor temperature sensor 8 is lower than the temperature data of the outdoor temperature sensor 4 or the required indoor set temperature, the coil solenoid valve 7 installed on the indoor top coil 5 is closed, and the working fluid no longer acts. When the outdoor temperature is lower than the phase change temperature of the phase change metal material in the thermochromic adaptive passive radiation cooling coating 1, the solar reflectivity and mid-infrared emissivity of the adaptive passive radiation cooling coating 1 are reduced, and the passive radiation cooling function of the adaptive passive radiation cooling coating 1 is automatically closed to avoid overcooling in the building.

[0032] When the refrigeration device does not need to perform refrigeration for a long time, the protective cover 19 is controlled by the central controller 21 to cover the outer wall of the straight tube 2 to protect the adaptive passive radiation refrigeration coating 1.

[0033] The building is cooled by a refrigeration cycle. To ensure the continuous flow of the working fluid and sufficient heat exchange, in this embodiment, the inner diameter of the outdoor straight pipe 2 is 1.5 times the inner diameter of the indoor top coil 5, and the inner diameter of the outdoor straight pipe 2 is 20 mm. The indoor top coil 5 uses a high thermal conductivity copper tube, and the outdoor straight pipe 2 uses a polyvinyl chloride tube filled with high thermal conductivity carbon nanoparticles. The wall thickness of both is 2 mm. Each floor of the building uses an outdoor temperature sensor 4 and an indoor temperature sensor 8, which are respectively arranged in the middle of the straight pipe 2 of each floor of the building and the middle of the top coil 5 to measure the temperature, and the temperature data is input into the central controller.

[0034] The phase change temperature of the phase change material in the adaptive passive radiation cooling coating 1 can be determined according to the characteristics of the region, climate, etc.

[0035] Generally speaking, the preset temperature of the controller of this device can be determined according to the regional climate conditions and the user's personal needs. When the temperature is higher than this value, the temperature-adaptive building energy-saving cooling device can enable the refrigeration function according to the difference between the set temperature and the indoor temperature to cool the interior of the building, or enter an emptying and dormant state when not in use.

[0036] This adaptive energy-saving indoor temperature control device can be used in cold storage, data centers, warehouses, residential and office buildings, and is particularly suitable for buildings or devices with high internal heat generation, such as machine rooms, boiler rooms, steelmaking workshops, and transformer boxes. At the same time, the corresponding preset temperature can be determined according to specific needs and the appropriate adaptive passive radiation cooling coating can be selected.

[0037] The adaptive building energy-saving and cooling device provided by the present invention can achieve effective cooling of the interior of the building through passive radiation refrigeration technology. By introducing the working fluid into the indoor ceiling for direct heat exchange, the heat exchange efficiency is higher. At the same time, the working state can be automatically adjusted according to the self-modulation effect of the adaptive passive radiation refrigeration coating and the difference between the indoor and outdoor temperatures and the preset temperature to avoid overcooling of the building, thereby reducing energy consumption for the building throughout the year. It has the advantages of energy saving and environmental protection, simple operation, wide application range, etc., and has high application value.

[0038] The present invention illustrates the principle and implementation mode of the present invention through examples. The description of the above examples is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention. Variations or substitutions based on the present invention are all included in the scope defined by the claims of the present invention.

Claims

1. A dual temperature adaptive building cooling and energy saving device based on passive radiation cooling, characterized in that: It consists of outdoor straight tubes coated with adaptive passive radiation cooling coating, indoor top coils for heat exchange, top liquid storage tanks, bottom liquid storage tanks, solenoid valves and temperature sensors connected to a central controller, and a connected piping system. Multiple straight tubes with multiple sections are regularly and densely arranged on the outdoor top of the building and on the sunny walls of each floor, and each section of the single straight tube is connected; the straight tube is installed with an outdoor temperature sensor, and the upper end of the straight tube is connected to the inlet and outlet of the indoor top coil through two three-way joints, and a straight tube solenoid valve is installed between the two three-way joints, and the three-way joint is a polymer plastic pipe with low thermal conductivity; the indoor top coil is installed with an indoor temperature sensor and a coil solenoid valve, and the outdoor vertically placed straight tube The bottom of the pipeline is connected to a collecting pipe, which is connected to a connection port of a liquid pump in a bottom liquid storage tank, and another connection port of the liquid pump is connected to a return pipe. A return pipe solenoid valve is installed on the return pipe, and the other end of the return pipe is connected to a liquid storage tank on the top of the building. A liquid level gauge is installed on the top liquid storage tank, and at each outlet thereof, a liquid replenishment solenoid valve is installed to communicate with an outdoor top straight pipe, and the liquid level gauge installed thereon can monitor the liquid level in the top liquid storage tank; the outer sides of the multiple sections of straight pipes on the top and each layer of the sunny wall and the surface of the top liquid storage tank are coated with an adaptive passive radiation cooling coating, and the formula, coating area and thickness of the adaptive passive radiation cooling coating, and the number of cooling straight pipes can be configured according to regional and climatic characteristics.

2. According to claim 1, a dual temperature adaptive building cooling and energy saving device based on passive radiation cooling is characterized in that: Turbulator elements are installed in the pipeline to enhance heat exchange, and protective devices are installed on the outside of the outdoor straight pipe to extend the service life of the adaptive passive radiation cooling coating.

3. The dual temperature adaptive building cooling and energy saving device based on passive radiation cooling according to claim 1 is characterized in that: The adaptive passive radiation cooling coating is a thermochromic radiation cooling coating, which is mainly composed of a polymer substrate, inorganic particles and a phase-change metal material, and has a multi-level micro-nano structure of pores, particles and fibers.

4. The dual temperature adaptive building cooling and energy saving device based on passive radiation cooling according to claim 3 is characterized in that: The polymer base material is TPU, PVDF or PMMA, the inorganic particle material is ZrO2, SiO2 or BaSO4, and the phase change metal material is VO2.

5. The dual temperature adaptive building cooling and energy saving device based on passive radiation cooling according to claim 1 is characterized in that: Each solenoid valve installed on the outdoor pipeline is connected to the central controller; the indoor and outdoor temperature sensors are connected to the central controller, and the central controller collects data from the indoor and outdoor temperature sensors. The indoor temperature sensor collects the real-time indoor temperature, and the outdoor temperature sensor collects the working fluid temperature in the vertical pipe; after comparing the temperature data collected by the temperature sensors in the indoor and outdoor pipelines with the preset temperature of the system, the opening and closing of the solenoid valves at different positions in the pipeline are controlled to realize the management of the opening and closing of the passive radiation cooling effect of the building; the second level of adaptive temperature regulation is realized through the central controller.

6. The dual temperature adaptive building cooling and energy saving device based on passive radiation cooling according to claim 1 is characterized in that: The liquid storage tank on the top of the building is connected to the water supply pipeline of the building, and can be directly replenished when the working fluid is water; or when the working fluid is a refrigerant or a nanofluid, it can be directly added to the liquid storage tank on the top of the building.

7. The dual temperature adaptive building cooling and energy saving device based on passive radiation cooling according to claim 1 is characterized in that: The inner diameter of the outdoor straight pipe is 1.2 to 2.2 times the inner diameter of the indoor top coil; the building is cooled by a refrigeration cycle, and in order to ensure the continuous flow of the working fluid and sufficient heat exchange, the inner diameter of the outdoor straight pipe is 18 to 40 mm; the indoor top coil can use high thermal conductivity aluminum tubes, copper tubes or polymer plastic tubes filled with high thermal conductivity materials; the outdoor straight pipe uses metal tubes with different thermal conductivity coefficients or polymer plastic tubes filled with high thermal conductivity materials; the wall thickness of both is selected according to the pipe diameter 2 to 10 mm.

8. The dual temperature adaptive building cooling and energy saving device based on passive radiation cooling according to claim 1 is characterized in that: The pipeline is fixed to the building wall by a water pipe fixing clamp, and a retractable protective cover is installed on the surface of the straight pipe. Under the control of the central controller, the retractable protective cover drives the ball screw slide rail to move up and down to cover the surface of the straight pipe or retract and store at the bottom of the straight pipe, thereby realizing the protection of the adaptive passive radiation cooling coating on the pipe wall in bad weather.

9. The dual temperature adaptive building cooling and energy saving device based on passive radiation cooling according to claim 1 is characterized in that: The device can be powered by solar panels or connected to the building power supply system.

Images