Air precooling

Abstract

The present application relates to a system comprising at least one radiative cooling material and at least one air intake. The at least one radiative cooling material is arranged upstream of the at least one air intake. Air moves from the radiative cooling material to the at least one air intake such that the air is cooled using the radiative cooling material before entering the at least one air intake. The radiative cooling material and the air intake can be arranged on a roof of a building and the air intake can provide the cooled air into the building. The air intake can comprise any one or more of a vent, an air conditioner, or an air cooled condenser. The radiative cooling material can comprise an opening through which the air flows before entering the at least one air intake, wherein the flow of air through the opening causes the air to be pre-cooled.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 559,693, filed February 29, 2024, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure relates to radiative cooling systems for cooling air and other fluids. More specifically, this disclosure relates to precooling air, for example, entering any suitable air inlet (e.g., which may be itself an air intake system or a component of an air intake system), which may be connected, for example, to a heating, ventilation, air conditioning / refrigeration (HVAC / R) unit, a building, or any other suitable structure. As used herein, air can be considered “precooled” if it is cooled before entering the air inlet. Summary of the Invention

[0004] Air intakes (such as roof or building air intake vents) and air handling equipment (such as condensers, fluid coolers, any suitable HVAC equipment, and other air cooling devices or air exchange systems) are typically located on the roof of a building. On certain days, especially in summer and particularly in hot climates, some roofs (such as dark and white roofs) may be hotter than the ambient air (e.g., above or around the building). Such hot roofs can heat the air traveling or residing near the intake system (e.g., including the air intake and optionally the air handling equipment). Therefore, the air received at the air intake may be warmer than the ambient air. Consequently, cooling systems coupled to the air intake (e.g., HVAC systems and / or any other suitable cooling systems that may include the aforementioned air handling equipment) may be forced to cool air that is warmer than the ambient air. Forced cooling of warmer air increases the energy demand associated with the cooling system and may cause the cooling system to output warmer air than it would output if it received intake air at ambient temperature. Therefore, warmer intake air may reduce comfort or exacerbate the cooling requirements of interior building spaces.

[0005] According to embodiments of this disclosure, a radiant cooling system is provided for precooling (i.e., cooling the air before it enters the air inlet) air and other fluids entering an air inlet (e.g., an air inlet for HVAC / R equipment, a building, any suitable air intake system, any other suitable structure, or any combination thereof). As described above, the air inlet can be coupled to a cooling system that may include any suitable air handling equipment (e.g., a condenser, evaporator, heat pump, or any other cooling device). In some embodiments, the system includes a roof, at least one radiant cooling material on the roof, and a fluid exchange system on the roof, wherein the fluid exchange system allows working fluids (including, but not limited to, air) to enter and exit the building under the roof, and at least one radiant cooling material cools the working fluids before they enter the building. In some embodiments, the fluid exchange system is any of an air conditioner, condenser, vent, or other air delivery system. In some embodiments, the fluid is air; in other embodiments, the fluid is a liquid including water or any suitable coolant. In some embodiments, the radiative cooling material is integrated with an air delivery system or configured to form a specific airflow path, such that more of the air entering the delivery system is exposed to the cooling surface of the radiative cooling material and is therefore cooled to a greater extent.

[0006] According to embodiments of this disclosure, the system includes at least one radiative cooling material and at least one air inlet. The at least one radiative cooling material is disposed upstream of the at least one air inlet. Air moves from the radiative cooling material to the at least one air inlet such that the air is cooled by the radiative cooling material before entering the at least one air inlet. The radiative cooling material and the air inlet may be disposed on the roof of a building, and the air inlet may supply cooled air into the building. The air inlet may include any one or more of a vent, an air conditioner, or an air-cooled condenser. The radiative cooling material may include openings through which air flows before entering the at least one air inlet, wherein the air flowing through the openings causes the air to be pre-cooled. Attached Figure Description

[0007] The above and other objects and advantages of this disclosure will become apparent when considered in conjunction with the accompanying drawings, wherein like reference numerals always refer to like parts, and wherein:

[0008] Figure 1 This is an illustrative diagram showing that the air entering the condenser exceeds the ambient temperature according to some embodiments of this disclosure;

[0009] Figure 2 This is an illustrative schematic diagram of an air-cooled condenser that cools the air inlet with a radiative cooling film according to some embodiments of the present disclosure;

[0010] Figure 3 This is an illustrative schematic diagram of a roof vent that cools the air inlet with a radiative cooling film according to some embodiments of the present disclosure;

[0011] Figure 4 This is a first illustrative schematic diagram of a roof vent having a baffled radiant cooling material for cooling the intake air and directing the intake air to the vent according to some embodiments of the present disclosure;

[0012] Figure 5 This is a second illustrative schematic diagram of a roof vent having a baffled radiant cooling material for cooling the intake air and directing the intake air to the vent according to some embodiments of the present disclosure;

[0013] Figure 6 This is an illustrative schematic diagram of a roof vent having a radiant cooling material, a thermal mass body, and a windproof screen for cooling the intake air and guiding the intake air to the vent, according to some embodiments of the present disclosure.

[0014] Figure 7 This is an illustrative schematic diagram of a roof vent having a breathable radiative cooling material, a thermal mass, and a windproof screen for cooling the intake air and guiding the intake air to the vent, according to some embodiments of the present disclosure.

[0015] Figures 8A-8B This is a first illustrative schematic diagram of a roof vent having a porous radiant material for cooling the intake air and directing the intake air to the vent and arranged above a support grid, according to some embodiments of the present disclosure.

[0016] Figures 9A-9B This is a second illustrative schematic diagram of a roof vent having a porous radiating material for cooling the intake air and directing the intake air to the vent and arranged above a support grid, according to some embodiments of the present disclosure;

[0017] Figure 10 This is an illustrative schematic diagram of a roof vent having radiant cooling material and heat exchange fins for cooling the intake air and guiding the intake air to the vent according to some embodiments of the present disclosure.

[0018] Figure 11 This is an illustrative schematic diagram of a roof having radiant cooling material, windbreaks, and perimeter walls for cooling intake air and guiding it to vents, according to some embodiments of the present disclosure.

[0019] Figure 12 This is a first illustrative schematic diagram of a radiative cooling surface connected to a thermal mass body via a heat conduction path according to some embodiments of the present disclosure;

[0020] Figure 13This is a second illustrative schematic diagram of a radiative cooling surface connected to a thermal mass body via a heat conduction path according to some embodiments of the present disclosure;

[0021] Figure 14 This is an illustrative radiative cooling system for cooling airflows into a building, according to some embodiments of the present disclosure;

[0022] Figure 15 This is an illustrative radiative cooling system having an internal barrier for releasing warm air and directing cold air to roof vents, according to some embodiments of the present disclosure;

[0023] Figure 16 These are illustrative sectional and isometric views of a radiant cooling system having an inclined plenum chamber connected to a roof vent, according to some embodiments of the present disclosure; and

[0024] Figure 17 A flowchart of an exemplary air precooling method according to some embodiments of the present disclosure is shown. Detailed Implementation

[0025] Figure 1 An illustrative temperature measurement 100 recorded at the roof of a building is shown according to some embodiments of the present disclosure. Figure 1 The top panel includes exemplary data showing: a temperature 110 measured below a condenser (such as the condenser of a building's air handling system), labeled "Air temperature entering the air-cooled condenser," and a temperature 120 measured at a distance of 1 m above the roof using an exhaust radiation shield, labeled "Ambient air temperature measured with a radiation shield." Figure 1 The bottom panel shows a temperature difference of 130 (e.g., temperature 110 minus temperature 120). On average, the inlet air temperature seen by the condenser is 3 to 5 degrees Fahrenheit higher than the actual ambient air temperature due to roof heating. Because of the way the sun heats the roof, the air entering the condenser is heated by the hot roof, thus increasing the resulting cooling load on the condenser. This additional heat represents a reduction in energy consumption and / or performance of HVAC equipment and increases the total cooling load of any building with a hot roof (e.g., it can characterize any building for which the temperature of the air entering the building via the roof intake system is higher than the ambient air temperature).

[0026] To overcome this energy consumption and / or performance degradation, according to some embodiments of this disclosure, radiative cooling materials, structures, systems, and methods for precooling air (e.g., at roof interfaces) are disclosed, enabling air handling equipment (e.g., on rooftops) to operate more efficiently. In some embodiments, for every 1 degree Fahrenheit reduction in the inlet air temperature entering the air-cooled condenser, the connected refrigeration or air conditioning system can see a 1% increase in efficiency. In some embodiments, the connected air system can gain even greater benefits if the radiative cooling system extends the number of hours that outdoor energy-saving modes (e.g., outdoor air entering the air handling system) can occur.

[0027] According to some embodiments of this disclosure, radiative cooling materials, films, panels, or other structures are applied to cool roof air. In some embodiments, various arrangements of radiative cooling materials are disclosed to improve the cooling efficiency of the system. In some embodiments, the building has a large amount of roof insulation, making direct placement of radiative cooling materials on the roof not very effective for cooling. Therefore, structures for directly cooling air before it enters the building, vents, condensers, or other air handling structures are disclosed.

[0028] Figure 2 An illustrative structure 200 is shown, according to some embodiments of the present disclosure, including a radiative cooling material 201 (e.g., a radiative cooling film) to precool air entering a condenser or fluid cooler. As shown by the air inlet flow path 202, air is drawn around or through the radiative cooling surface (which may have holes, slits, or other perforations). Due to contact with the radiative cooling material 201, the air is cooled before entering the air handling system 203. In some embodiments, such as... Figure 2 As shown, the intake system is an air-cooled condenser with an intake port 202 and an exhaust port 204, but any suitable intake device can be used. In some embodiments, radiative cooling material is arranged above the roof (e.g., a gap exists between the cooling material and the roof). Intake air flows through the gap and is cooled before entering the air-cooled condenser. In some embodiments, a seal 205 is arranged such that warm air outside the intake plenum cannot enter the air cavity and mix with the intake air, and that air cooled by the radiative cooling film cannot leave the air cavity. Structure 200 is arranged on top of roof 206, and the interior of any suitable building can be located below it.

[0029] Figure 3An illustrative structure 300 according to some embodiments of the present disclosure is shown, including a radiative cooling material 301 applied directly to the roof 303 surrounding the air intake vent 302 and directly to the air intake vent 302 itself. Based on the geometry of the vent and the natural flow path 304 that drives the air intake, the intake air arriving at the vent 302 is cooled as it travels through the radiative cooling material 301.

[0030] Such as at least in Figures 3 to 5 As shown, and applicable to any embodiment of the subject matter of this disclosure, a radiative cooling material can be applied to the underside of a roof vent, preventing it from being directly exposed to sunlight. As a result, the radiative cooling material can maintain a lower temperature, thereby providing better cooling performance.

[0031] Figure 4 An illustrative structure 400 is shown, according to some embodiments of the present disclosure, including a radiative cooling surface 401 (e.g., a panel, support, or other structure to which a radiative cooling material is applied, such as as a membrane), arranged above a roof 410 and having an air gap 403 between the cooling surface 401 and the roof 410. Based on the geometry of the radiative cooling surface 401, air is oriented to grooves surrounding a roof vent 404. The specific geometry of the radiative cooling material (which includes the grooves) is achieved through a corresponding arrangement of structures to which the radiative cooling material is applied. Support members 405 for the structure extend from the top of the roof to the bottom of the structure, as shown. Air in the grooves (and air in contact with the baffled cooling material oriented toward the grooves) is cooled by the radiative cooling material and thus becomes denser. As a result, cooler air is trapped or retained around the vent because it is denser than the surrounding air. Furthermore, the air entering the roof vent 406 is cooled before entering the roof vent 404.

[0032] In some embodiments, structure 400 further includes radiative cooling material 402 applied to the top and / or bottom sides of roof vent 404. Radiative cooling material 402 may be the same material applied to radiative cooling structure 401. Radiative cooling material 402 can further cool the air intake 406, and radiative cooling material 402 can also cool the roof vent 404. Having a cooler roof vent will further facilitate pre-cooling of the air before it enters the condenser or other components of the air handling system.

[0033] Figure 5An illustrative structure 500 is shown according to some embodiments of the present disclosure, including an air gap 503 between a roof 510 and a radiant cooling structure 501, wherein the air gap 503 is configured to provide an air cavity that supplies cooled air to a roof vent 504 at an air inlet 506. In some embodiments, the radiant cooling structure 501 includes a flexible substrate on which a radiant cooling material is applied. The flexible substrate and the radiant cooling material may be arranged around the roof air inlet vent 504 (e.g., using tension or any other suitable force) to direct cooled air to the roof vent air inlet according to the air inlet 506. As described above, the flexible substrate may be configured to seal the air cavity from air located above the radiant cooling structure 501 (relative to the roof). In some embodiments, the radiant cooling material included in the radiant cooling structure 501 may have holes, slits, perforations, or other permeable features that allow air to flow through the radiant cooling structure 501. In some embodiments, water (e.g., from precipitation or condensation) may be drained from the surface and optionally collected (e.g., similar to...). Figures 13 to 14 (The arrangement shown).

[0034] In some embodiments, structure 500 further includes a radiative cooling material 502 applied to the underside of the roof vent 504. The radiative cooling material 502 may be the same material applied to the radiative cooling structure 501. The radiative cooling material 502 may further cool the air in the air chamber 503 and the air in the intake 506. Any roof vent, including all roof vents described in this disclosure, may have radiative cooling material applied to its top and / or bottom sides. For reasons of brevity, such top and / or bottom radiative cooling materials may not be explicitly mentioned in connection with other embodiments of this disclosure, but such top and / or bottom radiative cooling materials are included or considered in connection with these other structures.

[0035] Figure 6An illustrative structure 600 including a radiative cooling material 601 according to some embodiments of the present disclosure is shown. The radiative cooling material 601 is disposed below a windshield 603 and above (e.g., in direct contact with) a thermal mass 605, all disposed above a roof 610. In some embodiments, the windshield 603 is made of a mesh or an infrared-transparent material. In some embodiments, the windshield 603 is transparent to visible light. The windshield 603 prevents convection from warming the surface of the radiative cooling material 601 and also keeps the surface clean. The cooling power of the radiative cooling material 601 may be reduced by the accumulation of dirt, debris, or other materials (e.g., radiative cooling materials are most effective when clean). Therefore, the windshield 603 can improve the performance of the radiative cooling material 601 by preventing convection warming and further by keeping its surface clean. In some embodiments, the windshield 603 has snaps, hooks, or other attachments that allow the windshield 603 to be easily applied to and / or removed from the radiative cooling material 601. In some embodiments, the windscreen 603 may be removed or replaced once per cooling season or at any other suitable frequency.

[0036] Figure 6 A thermal mass 605 below the radiative cooling material 601 is also shown. As further described below, the thermal mass 605 may include a material that maintains a low temperature (due to being cooled by the radiative cooling panel) and thereby provides an additional cold surface capable of carrying away heat from the roof air (e.g., roof air entering the roof vent 604).

[0037] Figure 7An illustrative structure 700 is shown according to some embodiments of the present disclosure, comprising a breathable (e.g., perforated or stamped) radiative cooling material 701 disposed on a first side of a roof vent 704 below a windbreak 703 and on a second side of a roof vent 704 above (e.g., in direct contact with) a thermal mass body 705. The breathable radiative cooling material 701 can have improved cooling power compared to impermeable (e.g., unperforated or unstamped) radiative cooling materials due to having a larger surface area exposed to air, and further due to altered convection along the material surface. As mentioned above, the cooled air may become denser than the surrounding warmer air. The denser cooled air can remain within the air gap (e.g., which may be referred to as an air inlet) between the roof 710 and the cooling structure 700, even if the air gap may be unsealed (e.g., due to stamping or perforation in the breathable radiative cooling material 701). Even so, to limit the permeability of the air gap, the side edges of the air gap can be sealed against the top of the roof 710. As a result, as shown in the figure, there may be no direct flow path into the air gap (or there may be a restricted direct flow path) other than those through the permeable radiative cooling material 701.

[0038] For the reasons described above, any radiative cooling material described in association with embodiments of this disclosure can be made breathable (e.g., based on perforation, stamping, or other suitable processes). The degree of breathability can be configured to maximize the radiative cooling power of the corresponding breathable radiative cooling material. For example, breathability can be configured to increase surface area without causing significant mixing of cold air (e.g., below or in contact with the radiative cooling material) and warmer ambient air (e.g., unaffected by the radiative cooling material). Meanwhile, any breathable radiative cooling material described in association with embodiments of this disclosure can also be made impermeable and still serve the radiative cooling application associated with the corresponding structure.

[0039] Figure 8A The illustration shows, according to some embodiments of the present disclosure, a roof vent 804, a support grille 808 (e.g., where the support grille supports a support member to which radiant cooling material 801 is applied), and radiant cooling material 801 above the roof 810 (as per [reference]). Figure 8B A top view of the illustrative structure 800 (as further described). Figure 8AIn the top view, although radiative cooling material 801 is present, it is not explicitly shown to better illustrate the supporting grille 808 below. As shown, a flange or gasket 809 may be attached to the roof 810 and surround the supporting grille 808. Illustrative and non-limiting dimensions associated with structure 800 may be 10 feet x 10 feet for the roof vent 804 and 50 feet x 50 feet for the roof 810 (or at least 50 feet x 50 feet for the roof 810, where the flange or gasket 809 surrounding the supporting grille 808 occupies 50 feet x 50 feet, and the supporting grille 808 occupies a corresponding area). These illustrative dimensions may scale with the size / number of roof vents and / or the size / shape of the roof.

[0040] Figure 8B A side view of an illustrative structure 800 according to some embodiments of the present disclosure is shown, with Figure 8A The top view is associated with this. Radiative cooling material 801 is permeable to air (e.g., due to perforations (as noted), stamping, or otherwise made permeable) and is arranged on top of support grille 808 to form an air gap between the top of roof 810 and the bottom of radiative cooling material 801. In some embodiments, the height of the air gap is 1 foot; in other embodiments, other suitable air gap heights are also considered. In some embodiments, radiative cooling material 801 (e.g., based on attachment to support grille 808) is attached to roof 810 by means of a flange or gasket 809, as shown.

[0041] Similar to Figure 8A , Figure 9A A top view of an illustrative structure 900 including a circular support grid located above a roof, according to some embodiments of the present disclosure, is shown. Similar to... Figure 8B , Figure 9B A side view of an illustrative structure 900 according to some embodiments of the present disclosure is shown. Figure 9B This demonstrates how radiative cooling material with air gaps can be arranged on a roof and how it can be connected to the roof via sidewalls or gaskets. Structure 900 can correspond to structure 800 except for the shape of the supporting grille 908 and the corresponding radiative cooling material 901. That is, the description of structure 800 can be applied to structure 900, and will not be repeated for the sake of brevity.

[0042] Figure 10Illustrative structures 1000 and 1050 according to some embodiments of the present disclosure are shown, each including fins 1003 with corresponding radiative cooling material arranged above a roof 1010 and a roof vent 1004. In some embodiments, the fins 1003 provide additional surface area for cooling air entering the roof vent 1004, thereby increasing the radiative cooling power of structures 1000 and 1050. For example, as shown, the fins 1003 may be arranged within at least a portion (or any other suitable air handling device) of an air cavity that provides air intake to the roof vent 1004. In some embodiments, including as shown in structure 1000, the fins 1003 are arranged below a flat surface, and the radiative cooling material 1001 is arranged above the flat surface; thus, the radiative cooling material 1001 cools the fins 1003 through the flat surface. In some embodiments, as shown in the figure, in structure 1050, a radiative cooling material 1051 (represented by a gray curve positioned on top of a black curve) is arranged to be in direct contact with fins 1003 (represented by a black curve positioned below a gray curve). Therefore, the radiative cooling material 1051 directly cools the fins 1003 through conduction.

[0043] Figure 11 An illustrative structure 1100 according to some embodiments of the present disclosure is shown, comprising a radiative cooling material 1101, a roof vent 1104, a peripheral wall 1108 surrounding the radiative cooling material 1101 and the roof vent 1104, and a windbreak 1103 disposed above the roof vent 1104, all disposed above a roof 1110. That is, the radiative cooling material 1101 is applied to the roof 1110, surrounded within the peripheral wall 1108, and disposed below the windbreak 1103. In some embodiments, both the peripheral wall 1108 and the windbreak 1103 serve to reduce convective heating of the radiative cooling material 1101 and to keep the radiative cooling material 1101 clean. As shown, the radiative cooling material can be applied directly to the roof 1110 without an air gap between the roof 1110 and the radiative cooling material 1101 (e.g., similar to...). Figure 3 (The arrangement shown). In other embodiments, the radiative cooling material 1110 may be arranged to have an air gap between the roof 1110 and the radiative cooling material 1110 (e.g., similar to...). Figures 4 to 10 (Any arrangement shown).

[0044] Figure 12An illustrative structure 1200 is shown according to some embodiments of the present disclosure, including a radiative cooling material 1201 applied over a heat conduction path 1203. The heat conduction path 1203 is thermally coupled to a thermal mass 1205 (e.g., brick or ballast (as indicated), or any other suitable thermal mass). The thermal mass 1205 provides thermal energy storage for the cooling power of the radiative cooling material 1201. The heat conduction path 1203 thermally couples the radiative cooling surface of the radiative cooling material 1201 to the thermal mass. Therefore, the radiative cooling material 1201 can cool the thermal mass 1205, and the cooled thermal mass can pre-cool air entering an air handling system or any other suitable structure or device.

[0045] Figure 13 Illustrative structures 1300 and 1350 according to some embodiments of the present disclosure are shown, each representing an additional arrangement (compared to structure 1200) for thermally coupling radiative cooling material to a thermal mass. Structure 1300 includes a curved and concave radiative cooling material 1301 applied over a heat conduction path 1303 of a corresponding shape. The heat conduction path 1303 is thermally coupled to the thermal mass 1305. Structure 1350 includes an inclined and downwardly sloping radiative cooling material 1351 applied over a heat conduction path 1353 of a corresponding shape. The heat conduction path 1353 is thermally coupled to the thermal mass 1305. Structures 1300 and 1350 may be shaped (e.g., having a concave or downwardly sloping orientation) to prevent dirt from accumulating on the surface of the respective radiative cooling material. Structures 1300 and 1350 may also be shaped (e.g., having a concave or downwardly sloping orientation) for collecting water, as further described below.

[0046] In some embodiments, structures 1300 and 1350 each include a water collector 1307. For example, as shown, the water collector 1307 may be arranged at the edge of the radiant cooling material 1301 or the edge of the radiant cooling material 1351, such that the shape of the radiant cooling material directs gravity-driven water flow towards the water collector 1307. Therefore, condensate, dew, rainwater, or other moisture collected on the radiant cooling material 1301 or 1351 can be collected. In some embodiments, the water collector 1307 may be integrated with a drinking water system, allowing the collected water to be used as drinking water or for other suitable tasks (e.g., cooling, irrigation, manufacturing, or any other suitable task).

[0047] Figure 14An illustrative structure 1400, comprising a radiative cooling material 1401 according to some embodiments of the present disclosure, is shown. The radiative cooling material 1401 is thermally coupled to an air intake system on a roof 1410 (e.g., including a roof vent 1404, a fan 1406, an air cavity 1405, and an air inlet 1409, and surrounded by a peripheral wall 1408 and a substrate 1407). Structure 1400 can be used to control and pre-cool air flowing into any suitable building. In some embodiments, it includes, for example, […]. Figure 14 As shown, the radiative cooling material 1401 is breathable (e.g., having openings based on perforations, punching, slits, or otherwise), sealed to the peripheral wall 1408, and further sealed to the periphery of the roof vent 1404. Therefore, all (or at least most) of the air residing in the air cavity 1405 and the air entering the air inlet 1409 (e.g., as indicated by the arrows depicting airflow) passes through the breathable radiative cooling material 1401. The peripheral wall 1408 is mechanically connected to a substrate 1407 disposed above the roof 1410, such that an air gap exists between the roof 1410 and the substrate 1407 (e.g., the height of this gap is the same as the height of the support structure supporting the substrate 1407). The substrate 1407 separates the air gap directly above the roof 1410 from the air cavity 1405, which retains air flowing into the building through the air inlet 1409. As shown, the roof 1410 has an opening (which may be, for example, a vent or other controllable opening) through which air can be propelled into the building by a fan 1406 (or otherwise driven, e.g., via convection). An air chamber 1405 is connected to an opening in an air inlet 1409 and holds pre-cooled air, which can be cooled, for example, when drawn through an opening in the radiant cooling material 1401 and otherwise contacted with the underside of the radiant cooling material 1401. The fan 1406 directs this pre-cooled air into the building (e.g., where it may enter an air handling system, air conditioning system, or other suitable air exchange system).

[0048] As by Figure 14 As shown in the illustrations, in some embodiments, the radiation cooling material 1401 is inclined. For example, the radiation cooling material 1401 may be shaped in a downwardly inclined (relative to the center) manner, as shown by radiation cooling material 1411, or it may be shaped in an upwardly inclined manner, as shown by radiation cooling material 1421. Although components other than the peripheral wall 1408 and the substrate 1407 are from... Figure 14 The depiction in the illustrations is omitted, but this is only for clarity and ease of explanation; it will be understood that radiation cooling material 1411 or radiation cooling material 1421 can be integrated with other components of structure 1400, as shown.

[0049] like Figure 14As shown and as Figure 14 As indicated in the illustration, the peripheral wall 1408 may extend above the height of the radiant cooling materials 1401, 1411, or 1421. This extended wall may serve as a windbreak and / or a water collection basin. If the structure 1400 comprises a substantially flat radiant cooling material (e.g., radiant cooling material 1401), water collection holes may be included at any suitable location (e.g., as shown in...). Figure 14 (As indicated in the illustration). If structure 1400 includes a non-planar radiative cooling material (e.g., radiative cooling material 1411, radiative cooling material 1421, or any other suitable radiative cooling material), then at least one hole may be provided, arranged near the lowest point of the radiative cooling material and configured to release water (e.g., runoff) from the collection basin by gravity-driven flow. For example, as in combination with radiative cooling material 1411... Figure 14 As shown in the illustration, the at least one water collection hole may be located in the peripheral wall 1408; additionally, as combined with the radiative cooling material 1421 in... Figure 14 As shown in the illustration, the at least one water collection hole may be located in the substrate 1407. A corresponding collection system may be provided (e.g., as combined with...). Figure 13 (As shown and described) to capture runoff water.

[0050] Figure 15 An illustrative structure 1500 according to some embodiments of the present disclosure is shown, comprising a radiative cooling material 1501 arranged around a roof vent 1504 and located above a roof 1510, a support structure 1508, and an internal barrier 1506. In some embodiments, the structure 1500 is configured to feed pre-cooled air into an air cavity in the roof vent 1504. Due to the geometry of the support structure 1508 as shown and the density difference between cold and warm air as discussed, the structure 1500 directs warm air upward (away from the roof vent 1504) and guides cold air downward (towards the roof vent 1504). As shown, the radiative cooling material 1501 may be arranged on the top surface of the support structure 1508 and along at least some of the inner walls of the support structure 1508 (relative to the air cavity surrounding the roof vent 1504). Based on this arrangement, the air in the surrounding structure surrounded by the support structure 1508 is cooled, resulting in a cold intake at the roof vent 1504. As indicated and as described by Figure 15 As indicated by the first type of arrow, ambient air can be drawn into the support structure 1508 (e.g., due to convection). This air intake can impinge on the internal barrier 1506 (e.g., because the barrier is oriented perpendicular to the main flow direction of the air intake). As noted and as illustrated by Figure 15As indicated by the second type of arrow, relatively warm air rises from the inner barrier 1506 and exits from the support structure 1508. (As noted and as indicated by...) Figure 15 As indicated by the third type of arrow, relatively cool air descends from the inner barrier 1506, gathers around the roof vent 1504, and is eventually drawn into the roof vent 1504 as cool air. Before entering the roof vent 1504, this relatively cool air can be further cooled (e.g., by radiative cooling material 1501 on the inner wall of the support structure 1508 while remaining in the air cavity).

[0051] The support structure 1508 can draw in air from multiple sides at an elevated height (relative to the roof vent 1504). A portion of the radiative cooling material 1501 is applied to the top of the support structure 1508 to cool the air below it, which accumulates at the bottom of the support structure 1508 near the roof vent 1504 due to increased density. An internal barrier 1506 can also break up strong winds driving the surrounding air intake, increasing the amount of time the radiative cooling material 1501 pre-cools the intake air. As shown, warm air exhaust can occur through at least one vent arranged at the top of the support structure 1508, which will also facilitate regular air circulation through the surrounding structure.

[0052] In some embodiments, the support structure 1508 may be sealed along the top (e.g., there will be no top vent or opening for the exhaust of warm air), and warm air may simply reside at the top of the support structure 1508 (e.g., away from the roof vent 1504) and / or may flow out of the support structure 1508 through surrounding air intake channels.

[0053] Figure 16 Cross-sectional and isometric views of an illustrative radiative cooling system 1600 according to some embodiments of the present disclosure are shown, comprising radiative cooling material disposed on a roof and connected to roof vents. Consistent with other embodiments of the present disclosure, the roof has roof vents that introduce air into the building from an air intake path (e.g., an air cavity). A support structure is configured to form the air cavity and includes a pad base adhered to the roof. Radiative cooling material is applied to the top of this structure such that the radiative cooling material cools the air in the air cavity and thus the air in the air intake path. As shown in the isometric view, the radiative cooling material may cover a large portion of the roof to maximize the cooling power of the radiative cooling system 1600.

[0054] Figure 17 A flowchart of an exemplary air precooling method according to some embodiments of the present disclosure is shown. At step 1701, method 1700 includes applying a radiative cooling material (e.g., combined with...) Figures 2 to 16Any radiative cooling material shown or described may be arranged upstream of an air intake system (e.g., any roof vent shown in this disclosure, or any other suitable air intake system). At step 1702, method 1700 includes pre-cooling the air flowing into the air intake system based on the air being cooled by the radiative cooling material. The air may be cooled by the radiative cooling material by flowing along the radiative cooling material, flowing above the radiative cooling material, flowing around the radiative cooling material, or flowing through the radiative cooling material, or by any other interaction with the radiative cooling material.

[0055] Further details of various air precooling methods are provided below, consistent with some embodiments of this disclosure. For example, the following description may be applied to... Figures 2 to 17 Any one or more of the radiation cooling methods shown and described herein.

[0056] In some embodiments, radiative cooling material is used as part of a heat exchanger that exchanges heat between ambient air and any other suitable material, such as air in an air chamber, the interior space of a building, or a cooling fluid.

[0057] In some embodiments, the radiative cooling material can be positioned on the roof such that its surface has a relatively unobstructed view of the sky overhead. In some embodiments, the air cooled by the radiative cooling material can then be used in condensers, fluid coolers, building cooling, or any other suitable purpose. By cooling the intake air to below ambient temperature, condensers and fluid coolers can achieve greater heat dissipation, require less energy to cool the building, and allow the building to be made more comfortable with less air conditioning.

[0058] In some embodiments, the structure supporting the radiative cooling material is configured (e.g., through a suitable geometry) to exert a minimal pressure drop on the air flowing through or above it. The structure may also provide sufficient surface area to cool the flowing air. Therefore, the temperature of the cooled air can be reduced to below the ambient temperature measured on the building roof.

[0059] In some embodiments, when the radiative cooling material is used to cool air to below ambient temperature, the nominal heat emission of the radiative cooling material can be as high as 100 W / m² during the day. 2 Furthermore, this heat emission can exceed 100W / m² at night. 2 .

[0060] In some embodiments, convective heat transfer caused by wind or other fluid flow can warm the outward-facing surface of the radiative cooling material. Therefore, various screens, perimeter walls, baffles, and / or other techniques, as provided in some embodiments of this disclosure, can be combined with radiative cooling materials to control convective heating effects and improve cooling performance.

[0061] In some embodiments, the radiative cooling material is located on a roof and exposed to the sky, creating the possibility of it becoming dirty. A radiative cooling material with a dirty surface may not provide as much heat dissipation as it does with a clean surface. Therefore, various screens, perimeter walls, baffles, and / or other technologies, as provided in some embodiments of this disclosure, can be combined with the radiative cooling material to prevent dirt buildup and / or facilitate cleaning.

[0062] In some embodiments, when the radiative cooling device or structure is used as a precooler for air entering a building, the radiative cooling material may be applied directly to the roof around the air intake vents (e.g., without applying the material to the supporting structure), or the material may be applied to the structure. In some embodiments, the material and / or the supporting structure may direct the cooled air to the vents, condensers, or other air delivery systems.

[0063] In some embodiments, the radiant cooling structure can be applied to many different types of air intake vents, including louvered air intakes, fans, box-type roof vents, roof fans, hooded fans, any other suitable air intake devices, or any combination thereof. Additionally, the radiant cooling structure can be used in conjunction with fluid coolers, evaporative condensers, air-cooled condensers, any other suitable cooling devices, or any combination thereof.

[0064] In some embodiments, when the radiative cooling material is applied directly to the roof, a barrier may be created around the radiative cooling material to reduce the mixing of cooled air on the roof surface with free-flowing ambient air above the roof. This barrier may also direct cool air (e.g., due to its higher density than warmer air) to air inlets, fans, or other air delivery systems while preventing warm air from entering these same systems.

[0065] In some embodiments, to control airflow near the radiative cooling material, air can be drawn over, under, and / or around the radiative cooling material to maximize cooling by maximizing the amount of time the air is in contact with the radiative cooling material. In some embodiments, air can be drawn through a radiative cooling material having holes, perforations, or slits to maximize the amount of heat that the cooling surface can provide to the air. These holes, perforations, or slits may be collectively referred to as multiple openings in the radiative cooling material.

[0066] In some embodiments, the structure supporting the radiative cooling material can be directly mounted to the roof of a building using mechanical fasteners, or it can be ballasted using a material that can also act as a thermal energy storage material. For example, the structure supporting the radiative cooling material can be designed to have a thickness such that it will be cooled by the radiative cooling material at night and in the early morning (e.g., when the sun is not at or near the horizon), and this cooled support material can slowly release heat later in the day when the ambient temperature is warmer, thereby increasing the cooling power of the system by providing thermal energy storage.

[0067] In some embodiments, the structure supporting the radiative cooling material may be installed together with a thermal insulation element to improve the cooling of the air cavity surrounded (at least partially) by the radiative cooling material or at the surface of the radiative cooling material. In some embodiments, this insulation element improves cooling power when a large amount of heat is conducted through the roof, which would otherwise hinder the cooling performance of the radiative cooling material.

[0068] In some embodiments, cooling power and / or cooling efficiency can be further improved by using windscreens built into or around a structure supporting the radiative cooling material to minimize convective heat transfer to the surface of the radiative cooling material. In some embodiments, windscreens or other technologies can cause a layer of cold air (e.g., due to density, even without any seals or air chambers) to accumulate on the sky-facing surface of the radiative cooling material, and this layer of cold air can be directly connected to a vent or other air delivery system. In some embodiments, windscreens or other devices can also be used to force air to flow across or around the radiative cooling surface.

[0069] In some embodiments of this disclosure, any windscreen provided in some embodiments may be arranged at a distance of not less than 3 inches above the surface of the radiative cooling material to provide an air gap (e.g., forming a cooling air cavity) between the screen and the surface.

[0070] In some embodiments, the structure supporting the radiative cooling material may be glued or otherwise attached to the roof (or another suitable surface) via plastic baffles or gaskets. These support structures may be configured for temporary use and / or releasably fixed to the roof.

[0071] In some embodiments, the structure supporting the radiative cooling material has corrugations. The corrugations are configured to induce runoff of surface moisture (e.g., when it rains). This surface moisture runoff can remove debris (e.g., dust, dirt, or any other substance on the surface of the radiative cooling material) from the material, thus the corrugations help keep the material clean. In some embodiments, the low points in the corrugations may have slits, holes, or other drainage channels to remove and / or collect rainwater, debris, and other runoff.

[0072] In some embodiments, the radiative cooling material can cool the air below the dew point in the morning and evening, causing moisture to condense on the surface of the radiative cooling material. This moisture can be collected and harvested for use as drinking water by tilting the surface and placing water collection containers at the respective ends of the tilted structure.

[0073] In some embodiments, the radiative cooling material may have holes, slits, perforations, or other breathable features (e.g., any suitable plurality of openings) to allow air to flow through it. Allowing air to flow through the radiative cooling material can increase its cooling power. In some embodiments, the perforations, slits, holes, or other suitable openings are implemented such that they do not reduce the surface area of ​​the radiative cooling material facing the sky.

[0074] In some embodiments, the structure supporting the radiant cooling material is arranged to be in direct contact with existing exhaust or intake vents (e.g., including intake plenum chambers). The radiant cooling material may be in direct contact with such vents using rubber gaskets, shields, or other substantially airtight linings to minimize (or eliminate) the entry of warm air (e.g., warm air heated by the roof) into the pre-cooled air chamber or corresponding air handling system.

[0075] In some embodiments, the structure supporting the radiative cooling material may have access walkways that allow access to intake equipment, exhaust vents, fluid coolers, and condenser equipment (e.g., for maintenance).

[0076] In some embodiments, a flexible air shield or cover may be provided between the edge of the vent and the structure that retains the radiative cooling material.

[0077] In some embodiments, the radiative cooling system itself may be incorporated into (or in direct contact with) the roof of a building (e.g., a barn, greenhouse, or data center) so that air is cooled as it is drawn into the lower level of the building.

[0078] In some embodiments, for a given roof vent, the volume of airflow through that vent determines the area of ​​suitable radiative cooling material to be applied to the roof. For the volumetric airflow rate Q, low and high area estimates can be determined by the following formula:

[0079]

[0080] Where ρ is the density of air, and c pHere, ΔT is the specific heat capacity of air, ΔT is the temperature difference between the surface and the incoming air, and the radiative cooling heat flux is a function of the temperature difference between the ambient temperature and the surface temperature. Additionally, con is a system constant constrained by site conditions and can be used to estimate the area of ​​radiative cooling material required to cool sufficient air for this application. That is, the size of the radiative cooling material can be configured according to the anticipated cooling requirements and / or the cooling power required for a given site.

[0081] In some embodiments, the radiative cooling material is configured to integrate with existing buildings, roofs, condensers, and fluid coolers with minimal alteration to the building's roof. Compared to evaporative cooling systems, the corresponding radiative cooling systems do not require the use of water.

[0082] In some embodiments, a thermomass is provided for storing cryogenic thermal energy generated by a radiative cooling material. The thermomass material may have a relatively high specific heat capacity (e.g., measured in J / kgK) to effectively maintain a relatively low temperature and a high thermal conductivity (e.g., measured in W / mK) to avoid a significant temperature difference between the air and the radiative cooling material. The thermomass may, for example, be arranged on a roof surface to maintain the radiative cooling system at a low temperature without further increasing the temperature difference between the radiative cooling material and the air. When the thermomass material is surface-thermally coupled to the radiative cooling material, a thermomass material with a relatively high heat capacity and a relatively high R-value may be preferred (e.g., relative to high heat capacity and low R-value). Certain non-limiting thermomass materials are considered and characterized in the table below:

[0083]

[0084] Table 1: List of exemplary thermomass materials and their related properties.

[0085] In some embodiments including any one or more of the above, the radiative cooling material, the structure to which the radiative cooling material is applied, and other materials forming the components of the radiative cooling system can be attached to the roof to which the radiative cooling system is applied using conventional roof supports, ballasts, or other fasteners.

[0086] In some embodiments, including any one or more of the above, the air cavity containing air cooled by the radiative cooling material can be sealed and isolated such that the cooled air cannot escape from the intake path and that warm air outside the air cavity cannot mix with the cooled air. Such cooled air may be referred to as pre-cooled air if it flows into any intake passage or system after being cooled.

[0087] In some embodiments, the radiative cooling material has a finned surface, and the finned surface is arranged opposite to the surface of the radiative cooling material facing the sky (e.g., thereby producing cooling). In some embodiments, an air cavity or other air intake passage may be configured such that air flows over the finned surface before entering the air intake system.

[0088] It should be understood that, in this disclosure, an air inlet can be any device, structure, or suitable combination thereof for receiving air (e.g., a roof vent, any other vent, any duct, any air pipe, any air passage, any other passage into the interior of a building, or any combination thereof). As used herein, an air intake system may include any suitable air inlet (e.g., any roof vent shown herein), and it may optionally further include any number of additional devices, materials, structures, or any combination thereof, for example, for guiding, conveying, handling, regulating, precooling, or otherwise managing the intake air. For example, an air intake system may include an air inlet (e.g., any roof vent disclosed herein), which may further include an air cavity disposed upstream of the air inlet (e.g., at least as shown below). Figures 2 to 11 and Figures 14 to 15 As shown in the diagram, and may further include an air-cooled condenser or other cooling device arranged downstream of the air inlet. The air intake system may include a radiant cooling material (e.g., coupled to the air inlet and / or air cavity) configured to cool the air before it enters the air inlet (i.e., pre-cool the air). The pre-cooled air may be supplied to the interior of the building, additional air handling equipment, any other suitable structure, or any combination thereof.

[0089] It should be understood that in this disclosure, when describing the arrangement of the radiative cooling structure, the terms "above," "on," and related directional language are used relative to a typical arrangement where the roof is located at the top of the building and the radiative cooling structure is located above the roof (e.g., from ground level).

[0090] The processes described above are intended to illustrate and not limit. Those skilled in the art will recognize that the steps of the processes described herein can be omitted, modified, combined, and / or rearranged without departing from the scope of the invention, and any additional steps can be performed.

[0091] The foregoing is merely an illustrative description of the principles of this disclosure, and various modifications can be made by those skilled in the art without departing from the scope of this disclosure. The above embodiments are presented for illustrative purposes and not for limitation. This disclosure may also take many forms other than those expressly described herein. Therefore, it should be emphasized that this disclosure is not limited to the methods, systems, and apparatus expressly disclosed, but is intended to include variations and modifications thereof within the spirit of the appended claims.

Claims

1. A system comprising: At least one radiation cooling material; as well as At least one air inlet, wherein: The at least one radiative cooling material is disposed upstream of the at least one air inlet, and air moves from the at least one radiative cooling material to the at least one air inlet such that the at least one radiative cooling material is used to cool the air before it enters the at least one air inlet.

2. The system according to claim 1, wherein: The at least one radiant cooling material and the at least one air inlet are arranged on the roof of the building; and The at least one air inlet supplies cooled air into the interior of the building.

3. The system according to claim 1, wherein the at least one air inlet comprises at least one of a vent, an air conditioner, or an air-cooled condenser.

4. The system according to claim 1, wherein: The at least one air inlet includes an outer surface and a vent, the outer surface being disposed upstream of the vent. The at least one radiative cooling material is disposed on the outer surface, and Cooling the air using the at least one radiative cooling material before it enters the at least one air inlet includes cooling the air by the outer surface before it enters the vent.

5. The system of claim 1, further comprising an air cavity disposed upstream of the at least one air inlet, wherein: The at least one radiative cooling material is arranged on at least one surface surrounding the air cavity, and Cooled air entering the at least one air inlet is supplied by the air chamber.

6. The system of claim 5, wherein the air cavity is formed by a volume surrounded on a first side by a roof, on a second side by the at least one air inlet, and on at least one other side by at least one surface on which the at least one radiative cooling material is disposed.

7. The system of claim 5, wherein the at least one air inlet is connected to an air intake static pressure box, wherein the air intake static pressure box forms a seal between the air chamber and the at least one air inlet.

8. The system of claim 1, wherein the at least one air inlet is located on the roof, and the at least one radiative cooling material is arranged above the roof such that an air gap exists between the roof and the at least one radiative cooling material.

9. The system of claim 1, further comprising a windproof shield disposed above the at least one radiant cooling material, wherein the windproof shield reduces convective heating of the at least one radiant cooling material.

10. The system of claim 1, further comprising a support structure, wherein: At least one radiative cooling material is applied to the supporting structure; and The support structure guides the cooled air into the at least one air inlet.

11. The system of claim 10, wherein the support structure includes corrugations configured to prevent liquid or solid substances from accumulating on the at least one radiative cooling material.

12. The system of claim 1, wherein the at least one radiative cooling material comprises a plurality of openings through which air flows before entering the at least one air inlet, wherein the air flowing through the plurality of openings causes the air to be cooled.

13. The system of claim 1, further comprising a thermal mass body thermally coupled to the at least one radiative cooling material.

14. The system of claim 1, further comprising a water collector configured to collect moisture accumulated on the at least one radiant cooling material.

15. A method comprising: At least one radiative cooling material is arranged upstream of at least one air inlet; as well as The at least one radiant cooling material is used to cool the air moving from the at least one radiant cooling material to the at least one air inlet, such that the air is cooled before entering the at least one air inlet.

16. The method of claim 15, wherein: The at least one radiant cooling material and the at least one air inlet are arranged on the roof of the building; and The at least one air inlet supplies cooled air into the interior of the building.

17. The method of claim 15, wherein: The at least one air inlet includes an outer surface and a vent, the outer surface being disposed upstream of the vent. Arranging the at least one radiative cooling material upstream of the at least one air inlet includes arranging the at least one radiative cooling material on the outer surface, and Cooling the air so that it is cooled before entering the at least one air inlet includes using the outer surface to cool the air so that it is cooled before entering the vent.

18. The method of claim 15, further comprising arranging an air cavity upstream of the at least one air inlet, wherein: The at least one radiative cooling material is arranged on at least one surface surrounding the air cavity, and Cooled air entering the at least one air inlet is supplied by the air chamber.

19. The method of claim 15, wherein the at least one radiative cooling material comprises a plurality of openings through which air flows before entering the at least one air inlet, wherein the air flowing through the plurality of openings causes the air to be cooled.

20. A system comprising: At least one radiation cooling material; At least one air inlet, wherein: The at least one radiative cooling material is disposed upstream of the at least one air inlet, and air moves from the at least one radiative cooling material to the at least one air inlet such that the at least one radiative cooling material is used to cool the air before it enters the at least one air inlet; as well as Air handling equipment, the air handling equipment being configured to: Cooled air is received from the at least one air inlet. Further cooling of the received cooled air, and Further cooling air is supplied to the cooling system.

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