A direct air intake water system with heat flow escaping effect coupled with sky radiation cooling

Abstract

This invention discloses a direct air-to-water system using heat flow effect coupled with sky radiation cooling, comprising: a heat flow-type water intake device, which includes at least one heat flow-type water intake unit, the heat flow-type water intake unit including a shell, a hot cavity, a cold cavity, and a microchannel assembly; the cold cavity is provided with a cold cavity heat exchanger and a cold cavity drain outlet; an air inlet pipe connected to the cold cavity air inlet; a cold cavity water collection pipe; a sky radiation cooling water collection device, which is provided with a humid air flow channel; the hot cavity exhaust outlet is connected to the inlet at one end of the humid air flow channel; the other end of the humid air flow channel is provided with a condensate outlet and a dry cold air outlet; a dry cold air pipe for introducing dry cold air into the cold cavity heat exchanger; a cooling water collection pipe; and a water collection tank, the cold cavity water collection pipe connecting the cold cavity drain outlet to the water collection tank, and the cooling water collection pipe connecting the condensate outlet to the water collection tank. The water intake system using this invention is unaffected by air humidity and can utilize renewable energy to obtain fresh water from the air.

Description

Technical Field

[0001] This invention relates to the field of air-to-water technology, and in particular to a direct air-to-water system that couples heat flow effect with sky radiation cooling. Background Technology

[0002] Freshwater, as one of the most precious natural resources, is a necessity for everyone and an important resource for socio-economic development. The Earth's total water volume is approximately 1.386 billion cubic kilometers, but freshwater accounts for only about 2.5%. Currently, the freshwater resources most easily accessible to humans are mainly river water, freshwater lakes and reservoirs, and shallow groundwater, accounting for about 0.3% of the global freshwater resources, demonstrating their scarcity. Due to population growth, climate change, and environmental pollution, one-sixth of the world's population faces water shortages. Therefore, increasing reliable access to freshwater and diversifying water sources is crucial for sustainable development.

[0003] Besides freshwater resources that can be directly utilized from nature, current freshwater production technologies mainly include seawater desalination, wastewater recycling and treatment, and direct air intake for water production.

[0004] Seawater desalination methods can be broadly categorized into three types: thermal distillation, membrane desalination, and interfacial solar steam generation. While seawater desalination is a mature and economically viable technology, it is heavily reliant on specific geographical locations; inland areas far from the coast cannot utilize this technology to collect freshwater. Furthermore, the desalination process requires substantial energy, and the discharged concentrated brine, corrosion products, and chemical cleaning agents can easily pollute the environment and damage marine ecosystems. In short, seawater desalination technology suffers from drawbacks such as high energy consumption, high pollution, high maintenance costs, and reliance on centralized production.

[0005] Municipal sewage and industrial wastewater, due to their large and stable flow rates and ease of collection, can serve as a secondary water source for cities. Wastewater treatment processes employ various physical and chemical methods, such as screening, flotation, oxidation, and disinfection. Treated reclaimed water can be used for agricultural irrigation, industrial cooling, domestic miscellaneous uses, groundwater recharge, and municipal water supply. Utilizing wastewater as a resource can effectively alleviate the imbalance between water supply and demand, yielding significant environmental and economic benefits. Different types of wastewater, due to their varying compositions, require different treatment strategies, making wastewater treatment processes complex and costly. Furthermore, wastewater treatment faces a series of challenges, including high energy consumption, low efficiency, and environmental pollution.

[0006] Atmospheric freshwater exists in the form of water vapor, accounting for approximately 0.04% of the global freshwater resources. Even in arid deserts, due to atmospheric circulation, the air still contains water vapor (about 1 / 5 of that in habitable areas), demonstrating that the air is also a significant source of freshwater. Air-based water harvesting technology can directly extract freshwater from the air. This technology essentially involves using physical or chemical methods to separate and collect water vapor from the air. Corresponding technologies include passive surface cooling water harvesting (i.e., mist and dew collection), active surface cooling water harvesting, and adsorption / absorption methods. Compared to other freshwater production technologies, air-based water harvesting produces usable freshwater that is not geographically limited, allowing access to freshwater resources even in desert regions. While mist and dew collection technologies are simple and practical, requiring no external energy input, they are primarily used in high relative humidity environments and are susceptible to the influence of the mist collector's structure. Adsorption-based air-based water extraction technology can produce water under low relative humidity, but the adsorption-desorption process consumes a large amount of energy; moreover, the performance of the water collection system depends on highly efficient adsorbents, and the use of chemical adsorbents poses environmental risks. Surface cooling water extraction technology relying on active refrigeration requires external energy input, is energy-intensive, and faces environmental problems caused by refrigerant leaks. In recent years, the application of sky radiation refrigeration technology to direct air-based water extraction to achieve zero-energy freshwater production has attracted widespread attention, but its application is currently limited to scenarios with relative humidity above 50%, and it cannot yet produce water under low relative humidity conditions.

[0007] In conclusion, under the current context of green development, there is an urgent need to develop a new freshwater production technology and corresponding equipment to effectively address the shortage of freshwater resources. Summary of the Invention

[0008] The purpose of this invention is to provide a direct air water intake system that couples heat flow effect with sky radiation cooling, thereby overcoming the shortcomings of sky radiation cooling technology and passive fog (dew) water collection technology in obtaining fresh water directly from the ambient air under low humidity conditions.

[0009] To achieve the above objectives, the present invention provides a direct air water intake system for heat flow effect coupled with sky radiation cooling, comprising: a heat flow water intake device, which includes at least one heat flow water intake unit, the heat flow water intake unit including a shell, a hot cavity, a cold cavity, and a microchannel group, wherein the hot cavity, the cold cavity, and the microchannel group are all disposed within the shell, and the cold cavity and the hot cavity are separated by the microchannel group; the microchannel group includes a plurality of microchannels connecting the cold cavity and the hot cavity, and the characteristic dimension of each microchannel is not less than the mean free path of water vapor molecules; a cold cavity heat exchanger is provided inside the cold cavity, a cold cavity air inlet is provided on the cold cavity, and a cold cavity drain outlet is provided at the bottom of the cold cavity; the outer wall of the hot cavity is made of a thermally conductive material, and a hot cavity exhaust outlet is provided on the hot cavity; an air inlet pipe communicating with the air inlet of the cold cavity, and the air inlet pipe having a... A valve; a cold cavity water collection pipe, the cold cavity drain outlet being connected to the inlet of the cold cavity water collection pipe; a sky radiation cooling water collection device, which has a humid air flow channel inside, the sky radiation cooling water collection device being able to radiate heat into space to cool the air in the humid air flow channel; a hot cavity exhaust port being connected to the inlet at one end of the humid air flow channel; the other end of the humid air flow channel having a condensate outlet and a dry cold air outlet, the condensate outlet being located below the dry cold air outlet; a dry cold air pipe, the inlet of which is connected to the dry cold air outlet, the outlet of which is connected to the inlet of the cold cavity heat exchanger; the outlet of the cold cavity heat exchanger being connected to the external environment through a one-way valve; a cooling water collection pipe, the inlet of which is connected to the condensate outlet; and a water collection tank, the outlets of the cold cavity water collection pipe and the cooling water collection pipe being connected to the water collection tank.

[0010] Preferably, in the above technical solution, when the number of the hot-flow-escape water intake units is two or more, the cold cavity air inlet of the first hot-flow-escape water intake unit is connected to the air inlet pipe, the cold cavity air inlet of the subsequent hot-flow-escape water intake unit is connected to the hot cavity exhaust port of the preceding hot-flow-escape water intake unit, and the hot cavity exhaust port of the last hot-flow-escape water intake unit is connected to the inlet of the humid air flow channel; wherein, each cold cavity drain outlet is connected to the cold cavity water collection pipe; the outlet of the first cold cavity heat exchanger is connected to the external environment through the one-way valve, the outlet of the subsequent cold cavity heat exchanger is connected to the inlet of the preceding cold cavity heat exchanger, and the inlet of the last cold cavity heat exchanger is connected to the outlet of the dry cold air pipe.

[0011] Preferably, in the above technical solution, the hot flow water intake unit further includes a pressure regulating valve, which connects the cold cavity and the hot cavity and is used to adjust the ratio of the temperature gradient to the pressure gradient between the cold cavity and the hot cavity.

[0012] Preferably, in the above technical solution, the bottom surface of the cold cavity is provided with an inclined horizontal plate, and the inclined horizontal plate is inclined downward from the end away from the cold cavity drain outlet towards the cold cavity drain outlet.

[0013] Preferably, in the above technical solution, the cold cavity heat exchanger is a tube-fin heat exchanger, and the surface of the cold cavity heat exchanger is coated with a hydrophobic coating; the cold cavity heat exchanger is inclined.

[0014] Preferably, in the above technical solution, the water collection tank, the cold cavity water collection pipe, the refrigeration water collection pipe and the dry cold air pipe are all covered with an external insulation layer.

[0015] Preferably, in the above technical solution, the outer wall of the hot cavity is provided with fins, and the fins are coated with a solar heat-absorbing coating.

[0016] Preferably, in the above technical solution, the outer wall of the cold cavity is provided with a heat insulation layer.

[0017] Preferably, the above technical solution further includes an air filter, which is provided on the air intake pipe.

[0018] Preferably, in the above technical solution, the sky radiation cooling water collection device includes a radiation cooling module and a converging heat mirror. The radiation cooling module includes a radiation cooling plate, a humid air flow channel, a metal plate wall, and a heat insulation material layer. The converging heat mirror is disposed above the radiation cooling plate. The humid air flow channel is inclined downward from its inlet direction to the condensate outlet direction. The top of the humid air flow channel is provided with the radiation cooling plate, and the bottom of the humid air flow channel is provided with a metal plate wall and a heat insulation material layer from the inside to the outside. The radiation cooling plate includes a multilayer radiation cooling film with selective emissivity and a support layer.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The water intake system of this invention uses the surrounding environment as a high-temperature heat source and space as a low-temperature heat source, requiring no additional energy input. It directly obtains fresh water from the atmosphere using a purely physical method. Compared with other fresh water production methods, it requires no chemical additives and produces no by-products. It is not limited by geographical location, and the processing technology is simple, achieving zero energy consumption, zero carbon emissions, and no environmental pollution. Furthermore, it adopts a heat flow-type water intake unit. Under the action of the heat flow effect, most of the water vapor molecules in the air are gathered in the cold cavity. Combined with the condensation effect of the cold cavity heat exchanger, the water vapor in the cold cavity is condensed into liquid water, which is finally discharged through the cold cavity drain outlet. It is not affected by air humidity and can obtain fresh water from the ambient air even in low humidity environments.

[0021] 2. The water intake system of this invention can use renewable and clean energy sources such as atmospheric ambient heat energy, solar radiation heat energy, and sky radiation cold energy as power sources. It directly uses atmospheric ambient heat energy and solar radiation heat energy to heat the hot cavity. Compared with the use of external heat sources, the structure is simpler and more compact. The cooling medium of the cold cavity heat exchanger uses dry cold air from the sky radiation cooling water collection device. It can utilize the system's own cold energy to further improve energy utilization efficiency. At the same time, it can avoid the precipitation of condensate in the cold cavity heat exchanger and corrosion of the components, thereby extending the service life of the cold cavity heat exchanger.

[0022] 3. The cold cavity heat exchanger of the present invention adopts a tube-fin heat exchanger, and the multi-layer fin arrangement can enhance the air heat exchange in the cold cavity; the cold cavity heat exchanger is arranged at a certain angle to avoid the water droplets condensing on the cold cavity heat exchanger interfering with each other when falling under their own gravity, so that the condensate can fall more smoothly onto the inclined horizontal plate and finally be discharged from the cold cavity drain port; at the same time, the surface of the cold cavity heat exchanger is coated with a hydrophobic material, which can reduce the possibility of frost formation and weaken the adverse effects caused by frost formation.

[0023] 4. The hot cavity of the present invention can be used directly as a heat exchanger. By adding fins to the outside of the hot cavity and coating the surface of the substrate with a solar heat-absorbing coating, the structure is simplified while enhancing the heat exchange capacity with the outside world.

[0024] 5. The sky radiation cooling water collection device of the present invention is equipped with a heat-concentrating mirror, which, compared with ordinary radiation coolers, can block atmospheric radiation in a large-angle direction, reduce the atmospheric radiation heat energy absorbed by the radiation cooling plate, thereby enhancing the cold energy acquisition capability. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the direct air intake water system of the present invention, which uses the heat flow effect coupled with sky radiation cooling.

[0026] Figure 2 This is a schematic diagram of the structure of the heat flow-out water intake unit through a perspective shell according to the present invention.

[0027] Figure 3 It is based on the present invention Figure 1 A magnified structural diagram of part A.

[0028] Explanation of key figure labels:

[0029] 1-Air filter, 2-Hot flow water intake unit, 201-Cold cavity, 202-Hot cavity, 203-Microchannel group, 204-Cold cavity heat exchanger, 205-Inclined connecting horizontal plate, 206-Pressure regulating valve, 207-Fins, 208-Insulation layer, 209-Cold cavity air inlet, 210-Inlet of cold cavity heat exchanger, 211-Hot cavity exhaust port, 212-Outlet of cold cavity heat exchanger, 3-Sky radiation cooling water collection device, 301-Heat converging mirror, 302-Radiation cooling plate, 303-Humid air flow channel, 304-Metal plate wall, 305-Insulation material layer, 4-Water collection tank, 5-Cold cavity water collection pipe, 6-Refrigeration water collection pipe, 7-Dry cold air pipe, 8-Inlet pipe, 9-Valve, 10-One-way valve. Detailed Implementation

[0030] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0031] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0032] Figures 1 to 3 The diagram shows a direct air water intake system for heat flow effect coupled with sky radiation cooling according to a preferred embodiment of the present invention. The water intake system includes a heat flow water intake device, an air inlet pipe 8, a cold cavity water collection pipe 5, a sky radiation cooling water collection device 3, a dry cold air pipe 7, a cooling water collection pipe 6, and a water collection tank 4.

[0033] refer to Figures 1 to 3The hot-fluid water intake device includes at least one hot-fluid water intake unit 2 for obtaining fresh water. The hot-fluid water intake unit 2 includes a shell, a hot cavity 202, a cold cavity 201, and a microchannel group 203. The hot cavity 202, cold cavity 201, and microchannel group 203 are all disposed within the shell, and the cold cavity 201 and hot cavity 202 are separated by the microchannel group 203. The microchannel group 203 includes several microchannels connecting the cold cavity 201 and the hot cavity 202, and the characteristic dimension of each microchannel is not less than the mean free path of water vapor molecules. The microchannel group 203 can be a common fiber membrane or a porous membrane with selective permeability. A cold cavity heat exchanger 204 is provided inside the cold cavity 201 for cooling the cold cavity 201; a cold cavity air inlet 209 is provided on the cold cavity 201, and a cold cavity drain outlet is provided at the bottom of the cold cavity 201 for draining condensate from the cold cavity 201. The hot cavity 202 is equipped with a hot cavity exhaust port 211, and its outer wall is made of a thermally conductive material. The hot cavity 202 is heated by atmospheric thermal energy and solar radiation, creating a temperature difference between the hot cavity 202 and the cold cavity 201. When the characteristic size of the microchannel is comparable to or smaller than the mean free path of gas molecules, gas molecules near the wall surface will spontaneously creep from the cold end to the hot end under the influence of the temperature gradient along the tangential direction of the wall surface, forming a thermal runoff. Therefore, air in the cold cavity 201 will enter the hot cavity 202 through the microchannel assembly 203, thereby increasing the pressure in the hot cavity 202 and decreasing the pressure in the cold cavity 201. The pressure difference between the hot cavity 202 and the cold cavity 201 generates a pressure-driven flow from the hot end to the cold end, gradually forming a dynamic equilibrium of flow. The superposition of the thermal runoff and the pressure-driven flow is the thermal runoff effect. Furthermore, the differences in the molecular characteristics of the various gas components in the air lead to different degrees of thermal runoff effect, resulting in flow differences. Components in the air whose molecular mean free path is similar to or larger than the characteristic size of the microchannel will enter the hot cavity 202 more quickly from the cold cavity 201 due to their higher molecular migration speed within the microchannel. Conversely, components whose molecular mean free path is smaller than the characteristic size of the microchannel will remain mostly in the cold cavity 201 due to their lower molecular migration speed. The final effect is that, because the mean free paths of oxygen and nitrogen molecules, the main components of the air, are slightly greater than those of water vapor molecules, they will flow from the cold cavity 201 into the hot cavity 202 faster than water vapor under the influence of the thermal runoff effect. This results in a decrease in the partial pressure of water vapor in the hot cavity 202 and an increase in the partial pressure of water vapor in the cold cavity 201, meaning that water vapor in the air is enriched in the cold cavity 201. The air inlet pipe 8 is connected to the cold cavity air inlet 209, allowing outside air to enter the thermal runoff water intake device. A valve 9 is installed on the air inlet pipe 8 for easy control of the opening and closing of the system. The cold cavity drain outlet is connected to the inlet of the cold cavity water collection pipe 5.The sky radiation cooling water collection device 3 is equipped with a humid air flow channel 303. Following the law of thermal radiation, the device operates at atmospheric temperature (high temperature) and radiates heat into space (low temperature), cooling the air within the humid air flow channel 303. This condenses water vapor in the air into liquid water, resulting in dry, cold air and condensate. The hot chamber exhaust port 211 is connected to the inlet at one end of the humid air flow channel 303. Air that has been fed water by the hot flow water collection unit 2 enters the humid air flow channel 303 for further condensation and water collection, simultaneously obtaining dry, cold air. The other end of the humid air flow channel 303 has a condensate outlet and a dry, cold air outlet, with the condensate outlet located below the dry, cold air outlet. The inlet of the dry cold air pipe 7 is connected to the dry cold air outlet, and the outlet of the dry cold air pipe 7 is connected to the inlet 210 of the cold cavity heat exchanger. The outlet 212 of the cold cavity heat exchanger is connected to the external environment through a one-way valve 10. Thus, the dry cold air generated by the sky radiation cooling water collection device 3 is directly used to cool the cold cavity 201 through the cold cavity heat exchanger 204. This ensures a sufficiently significant temperature difference between the hot cavity 202 and the cold cavity 201 to guarantee a sufficient heat flow effect and better utilization of the system's own cold energy, further improving energy efficiency. Simultaneously, it prevents condensation from forming inside the cold cavity heat exchanger 204, thus extending its service life. When the air rich in water vapor in the cold cavity 201 comes into contact with the cold cavity heat exchanger 204, it exchanges heat with it, releasing heat. When the air surrounding the cold cavity heat exchanger 204 is cooled and its temperature drops to the dew point temperature at the water vapor partial pressure, the water vapor in the air condenses into liquid water on the surface of the heat exchanger and drips onto the bottom surface of the cold cavity 201 under its own gravity, and is discharged from the cold cavity drain port. The inlet of the refrigeration water collection pipe 6 is connected to the condensate outlet; the outlets of both the cold cavity water collection pipe 5 and the refrigeration water collection pipe 6 are connected to the water collection tank 4, thereby collecting the condensate from the cold cavity 201 and the condensate from the humid air flow channel 303 into the water collection tank 4, achieving the purpose of obtaining fresh water from the air. The water intake system of this invention uses the surrounding environment as a high-temperature heat source and space as a low-temperature heat source, requiring no additional energy input. It directly obtains fresh water from the atmosphere using a purely physical method. Compared with other fresh water production methods, it requires no chemical additives and generates no by-products. It is not limited by geographical location, and the processing technology is simple, achieving zero energy consumption, zero carbon emissions, and no environmental pollution. Furthermore, the use of the heat flow-type water intake unit 2, under the action of the heat flow effect, can concentrate most of the water vapor molecules in the air into the cold cavity 201. Combined with the condensation effect of the cold cavity heat exchanger 204, the water vapor in the cold cavity 201 is condensed into liquid water, which is finally discharged through the cold cavity drain outlet. It is not affected by air humidity and can obtain fresh water from the ambient air even in low humidity environments.

[0034] refer to Figure 1 and Figure 2When there are two or more heat flow water intake units 2, they can be connected in series, parallel, or a combination of series and parallel. Since the effect of a single-stage heat flow water intake unit in separating and condensing water vapor is limited, in order to fully and efficiently obtain fresh water from the air, the heat flow water intake units 2 are arranged in a multi-stage series configuration to form a heat flow water intake device. The air flowing out of the hot cavity 202 of the previous stage heat flow water intake unit usually still contains water vapor, but the content is reduced, i.e., the water vapor partial pressure (or relative humidity) is lowered. Therefore, it is introduced into the cold cavity 201 of the next stage heat flow water intake unit 2, where water vapor continues to accumulate under the heat flow effect, repeating the above water intake process until the air enters the sky radiation cooling water collection device 3 for terminal condensation and water intake. Therefore, preferably, when there are two or more hot-flow-type water intake units 2, the cold cavity air inlet 209 of the first hot-flow-type water intake unit 2 is connected to the air inlet pipe 8, the cold cavity air inlet 209 of the subsequent hot-flow-type water intake unit 2 is connected to the hot cavity exhaust port 211 of the previous hot-flow-type water intake unit 2, and the hot cavity exhaust port 211 of the last hot-flow-type water intake unit 2 is connected to the inlet of the humid air flow channel 303, thereby connecting multiple hot-flow-type water intake units 2 in series. Each cold cavity drain outlet is connected to the cold cavity water collection pipe 5 to discharge the condensate from each cold cavity 201 into the water collection tank 4 through the cold cavity water collection pipe 5. The outlet 212 of the first cold cavity heat exchanger is connected to the external environment through a one-way valve 10, allowing only the dry, cold air after heat exchange to flow out of the hot flow water intake device. This prevents air from the external environment from entering the heat exchange tubes of the cold cavity heat exchanger 204, thus avoiding problems such as water vapor in the air condensing inside the heat exchange tubes of the cold cavity heat exchanger 204, which could lead to a decrease in the performance of the entire water intake system or even damage to the components. The outlet 212 of the next cold cavity heat exchanger is connected to the inlet 210 of the previous cold cavity heat exchanger, and the inlet 210 of the last cold cavity heat exchanger is connected to the outlet of the dry cold air pipe 7, so that the dry, cold air generated in the humid air flow channel 303 is sequentially transported from back to front to the cold cavity heat exchanger 204 of each stage of the hot flow water intake unit 2 to cool the cold cavity 201. That is, the dry cold air generated in the humid air channel 303 is transported to the cold cavity heat exchanger 204 of the last hot flow water intake unit 2, and flows from back to front through the cold cavity heat exchanger 204 of each hot flow water intake unit 2 until it flows through the first cold cavity heat exchanger 204 and is discharged from the hot flow water intake device.

[0035] refer to Figure 1 and Figure 2Preferably, the hot flow water intake unit 2 further includes a pressure regulating valve 206. The pressure regulating valve 206 is used to connect the cold cavity 201 and the hot cavity 202. The function of the pressure regulating valve 206 is to regulate the amount of air flowing from the hot cavity 202 to the cold cavity 201, thereby regulating the pressure difference between the gas in the cold cavity 201 and the gas in the hot cavity 202, so that an ideal ratio of temperature gradient to pressure gradient appears between the cold cavity 201 and the hot cavity 202, constructing a special hot flow effect, namely molecular exchange flow, which realizes that water vapor molecules in the air and other major component molecules flow in opposite directions in the microchannel, thereby enabling more effective enrichment of water vapor in the cold cavity 201 and improving the water intake effect.

[0036] refer to Figure 1 and Figure 2 The bottom surface of the cold cavity 201 can be horizontal or inclined. Preferably, the bottom surface of the cold cavity 201 is provided with an inclined horizontal connecting plate 205. The inclined horizontal connecting plate 205 is inclined downward from the end away from the cold cavity drain outlet towards the cold cavity drain outlet, thereby guiding the condensate dripping from the cold cavity heat exchanger 204 to the cold cavity drain outlet, which facilitates the discharge of condensate.

[0037] refer to Figure 1 and Figure 2 Preferably, the cold cavity heat exchanger 204 is a tube-fin heat exchanger. The arrangement of multiple layers of fins can enhance air heat exchange and improve the cooling effect of the cold cavity 201. In addition, the surface of the cold cavity heat exchanger 204 is coated with a hydrophobic coating, which can reduce the possibility of frost formation and weaken the adverse effects caused by frost. The cold cavity heat exchanger 204 is inclined, that is, it is arranged at a certain angle to avoid the water droplets condensed on the cold cavity heat exchanger 204 interfering with each other when falling under their own weight. This allows the condensate to fall more smoothly onto the inclined horizontal plate 205 and finally be discharged from the cold cavity drain port.

[0038] refer to Figure 1 Preferably, the water collection tank 4, the cold cavity water collection pipe 5, the refrigeration water collection pipe 6, and the dry cold air pipe 7 are all covered with an external insulation layer for heat preservation, so as to prevent the condensate in the water collection tank 4, the cold cavity water collection pipe 5, and the refrigeration water collection pipe 6 from evaporating again due to absorbing heat from the external environment, thereby reducing the water collection effect; at the same time, it also prevents the dry cold air in the dry cold air pipe 7 from absorbing heat from the external environment, causing the temperature to rise and weakening the heat flow effect.

[0039] refer to Figure 1 and Figure 2 Preferably, the outer wall of the hot cavity 202 is provided with fins 207, and the fins 207 are coated with solar heat-absorbing paint. By adding fins 207 to the outside of the hot cavity 202 and coating the substrate surface with solar heat-absorbing paint, the structure is simplified while the heat exchange capacity with the outside is enhanced.

[0040] refer to Figure 2Preferably, the outer wall of the cold cavity 201 is provided with a heat insulation layer 208 for heat preservation, to prevent the cold energy of the cold cavity 201 from being lost too quickly, and to improve the condensation effect of water vapor in the cold cavity 201.

[0041] refer to Figure 1 Preferably, the water intake system also includes an air filter 1. An air filter 1 is provided on the air inlet pipe 8. Outside air passes through the air filter 1 to filter impurities before entering the subsequent hot flow water intake device, which can avoid clogging the microchannel group and obtain relatively pure fresh water.

[0042] refer to Figure 1 and Figure 3 Preferably, the sky radiation cooling water collection device 3 includes a radiation cooling module and a converging heat mirror 301. The radiation cooling module includes a radiation cooling plate 302, a humid air flow channel 303, a metal plate wall 304, and a heat insulation material layer 305. The converging heat mirror 301 is located above the radiation cooling plate 302 and can block atmospheric radiation at large angles, reducing the atmospheric radiation heat energy absorbed by the radiation cooling plate 302, thereby enhancing the cold energy acquisition capability. The humid air flow channel 303 is inclined downward from its inlet direction to the condensate outlet direction to facilitate the outflow of condensate. The top of the humid air flow channel 303 is provided with the radiation cooling plate 302, and the bottom of the humid air flow channel 303 is provided with a metal plate wall 304 and a heat insulation material layer 305 from the inside to the outside. The radiation cooling plate 302 includes a multi-layer radiation cooling film with selective emissivity and a support layer. The radiant cooling plate 302 lowers its temperature by radiating heat into space. When its temperature is lower than the dew point temperature of the air in the humid air channel 303, water vapor in the air condenses on the radiant cooling plate 302, thus achieving condensation and water collection. The condensed water drips down to the lower part of the humid air channel 303 under the action of gravity and flows into the water collection tank 4 through the cooling water collection pipe 6 of the sky radiant cooling water collection device 3 for storage. The remaining dry cold air is used as a cooling medium and flows into the cold cavity heat exchanger 204 of each stage of the hot flow water collection unit 2 through the dry cold air pipe 7 to condense the water vapor in the air in the cold cavity 201, and then it is discharged into the environment.

[0043] During initial operation, when valve 9 is opened and the water intake system is just starting, the cold cavity heat exchanger 204 in the cold cavity 201 is not circulated with a cooling medium, and the cold cavity 201 has no cold source to provide cooling. However, since the hot cavity 202 is still heated by heat sources such as atmospheric ambient heat energy and solar radiation, a temperature difference still exists between the cold cavity 201 and the hot cavity 202. Although the temperature difference is relatively small, the heat flow effect will still occur. At this time, the air passing through the heat flow water intake unit 2 will accumulate water vapor in the cold cavity 201, and the water vapor partial pressure will increase. If the relative humidity of the outside air entering the water intake system is high, a small amount of condensate may be precipitated on the cold cavity heat exchanger 204; if the relative humidity of the outside air entering the water intake system is low, the relative humidity of the air in the cold cavity 201 may not have reached saturation, and no condensate will appear on the cold cavity heat exchanger 204. After air flows into the sky radiation cooling water collection device 3, producing a certain amount of condensate and dry cold air, the cold cavity heat exchanger 204 is circulated with dry cold air to cool the cold cavity 201. A significant amount of condensate appears on the cold cavity heat exchanger 204, and the hot air evaporation water collection unit 2 begins to collect fresh water. During this process, the temperature difference between the cold cavity 201 and the hot cavity 202 gradually increases, the hot air evaporation effect becomes more pronounced, and the efficiency of the cold cavity 201 in collecting fresh water increases until a stable equilibrium is reached. As the process continues, outside air is continuously transported from the air inlet pipe 8 to the hot air evaporation water collection device, sequentially entering each stage of the hot air evaporation water collection unit 2 for water collection, and finally flowing into the humid air flow channel 303 of the sky radiation cooling water collection device 3 for terminal condensation and water collection. The condensate discharged from each stage of the cold cavity 201 is transported to the water collection tank 4 through the cold cavity water collection pipe 5. The condensate flowing out of the humid air flow channel 303 is transported to the water collection tank 4 through the refrigeration water collection pipe 6. The dry cold air flowing out of the humid air flow channel 303 is sequentially transported to the cold cavity heat exchanger 204 of each stage of the hot air flow water intake unit 2 through the dry cold air pipe 7, and finally discharged into the external environment. In this cycle, each stage of the cold cavity 201 and the humid air flow channel 303 continuously discharges condensate into the water collection tank 4 to achieve the purpose of water intake.

[0044] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A direct air intake water system with heat flow escaping effect coupled with sky radiation cooling, characterized in that, include: A hot flow water intake device includes at least one hot flow water intake unit, wherein the hot flow water intake unit includes a shell, a hot cavity, a cold cavity, and a microchannel group, wherein the hot cavity, the cold cavity, and the microchannel group are all disposed within the shell, and the cold cavity and the hot cavity are separated by the microchannel group; The microchannel group includes several microchannels connecting the cold cavity and the hot cavity, and the characteristic dimension of each microchannel is not less than the mean free path of water vapor molecules; the cold cavity is provided with a cold cavity heat exchanger, the cold cavity is provided with a cold cavity air inlet, and the bottom of the cold cavity is provided with a cold cavity drain outlet; the outer wall of the hot cavity is made of thermally conductive material, and the hot cavity is provided with a hot cavity exhaust outlet. An air inlet pipe is connected to the air inlet of the cold cavity, and a valve is provided on the air inlet pipe; A cold cavity water collection pipe, wherein the cold cavity drain outlet is connected to the inlet of the cold cavity water collection pipe; The sky radiation cooling water collection device is equipped with a humid air flow channel. The sky radiation cooling water collection device can radiate heat into space to cool the air in the humid air flow channel. The hot cavity exhaust port is connected to the inlet at one end of the humid air flow channel; the other end of the humid air flow channel is provided with a condensate outlet and a dry cold air outlet, and the condensate outlet is located below the dry cold air outlet. A dry cold air duct, the inlet of which is connected to the dry cold air outlet, and the outlet of which is connected to the inlet of the cold cavity heat exchanger; the outlet of the cold cavity heat exchanger is connected to the external environment through a one-way valve. A cooling water collection pipe, the inlet of which is connected to the condensate outlet; and The water collection tank is connected to both the outlet of the cold cavity water collection pipe and the outlet of the refrigeration water collection pipe. The sky-radiative cooling water collection device includes a radiative cooling module and a converging heat mirror. The radiative cooling module includes a radiative cooling plate, a humid air flow channel, a metal plate wall, and a heat insulation material layer. The converging heat mirror is disposed above the radiative cooling plate. The humid air flow channel is inclined downward from its inlet direction to the condensate outlet direction. The radiative cooling plate is disposed at the top of the humid air flow channel, and the metal plate wall and the heat insulation material layer are disposed at the bottom of the humid air flow channel from the inside to the outside. The radiative cooling plate includes a multilayer radiative cooling film with selective emissivity and a support layer.

2. The direct air intake water system with heat flow escaping effect coupled with sky radiation cooling according to claim 1, characterized in that, When there are two or more hot-flow water intake units, the cold cavity air inlet of the first hot-flow water intake unit is connected to the air inlet pipe, the cold cavity air inlet of the subsequent hot-flow water intake unit is connected to the hot cavity exhaust port of the preceding hot-flow water intake unit, and the hot cavity exhaust port of the last hot-flow water intake unit is connected to the inlet of the humid air flow channel; wherein, each cold cavity drain outlet is connected to the cold cavity water collection pipe; the outlet of the first cold cavity heat exchanger is connected to the external environment through the one-way valve, the outlet of the subsequent cold cavity heat exchanger is connected to the inlet of the preceding cold cavity heat exchanger, and the inlet of the last cold cavity heat exchanger is connected to the outlet of the dry cold air pipe.

3. The direct air intake water system with heat flow effect coupled to sky radiation cooling according to claim 1, characterized in that, The hot-flow water intake unit also includes a pressure regulating valve, which connects the cold cavity and the hot cavity and is used to adjust the ratio of the temperature gradient to the pressure gradient between the cold cavity and the hot cavity.

4. The direct air intake water system with heat flow escaping effect coupled with sky radiation cooling according to claim 1, characterized in that, The bottom surface of the cold cavity is provided with an inclined horizontal plate, which is inclined downward from the end away from the cold cavity drain outlet towards the cold cavity drain outlet.

5. The direct air intake water system for heat flow escaping effect coupled with sky radiation cooling according to claim 1, characterized in that, The cold cavity heat exchanger is a tube-fin heat exchanger, and the surface of the cold cavity heat exchanger is coated with a hydrophobic coating; the cold cavity heat exchanger is inclined.

6. The direct air intake water system for heat flow escaping coupled with sky radiation cooling according to claim 1, characterized in that, The water collection tank, the cold cavity water collection pipe, the refrigeration water collection pipe, and the dry cold air pipe are all covered with an external insulation layer.

7. The direct air intake water system for heat flow escaping effect coupled with sky radiation cooling according to claim 1, characterized in that, The outer wall of the hot cavity is provided with fins, and the fins are coated with solar heat-absorbing paint.

8. The direct air intake water system for heat flow escaping coupled with sky radiation cooling according to claim 1, characterized in that, The outer wall of the cold cavity is provided with a heat insulation layer.

9. The direct air intake water system for heat flow escaping coupled with sky radiation cooling according to claim 1, characterized in that, It also includes an air filter, which is provided on the air intake pipe.

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