Air conditioning device using indirect evaporative cooling

Abstract

The device (1) for indirect evaporative cooling has an air inlet and a plurality of plates (10) forming a stack (2), each plate comprising a dry face opposite a wet face, the wet face of each plate being configured to be wetted by water, each plate being intended to be cooled by the evaporation of water from the wet face, each plate extending along a longitudinal axis. The stack (2) is held in a cooling module (3), which is configured to be inserted into a base (4) and removed from the base.

Description

TECHNICAL FIELD

[0001] The technical field of the invention is an air cooling device using indirect evaporative cooling.BACKGROUND ART

[0002] Air coolers using indirect evaporative cooling, also known as indirect adiabatic dew point coolers, have been known for several decades.

[0003] The principle of such coolers is illustrated in FIG. 1. It is based on the use of an evaporative heat exchanger, in which the incoming air (arrow D1 shown as a dotted line in FIG. 1) is cooled, without humidification, potentially to its dew point. Cooling occurs by air flows along a cooling plate P1, which is cooled by water evaporation. The cooling plate has a dry face, in contact with which the air to be cooled flows, and a wet face, moistened by water, the water being symbolized by circles in FIG. 1. In FIG. 1, the dashed arrow corresponds to the air to be cooled, the mixed dashed arrow represents the cooled air or air in the process of being cooled, and the solid arrow corresponds to the air flowing in the wet channel, the evaporation of which causes the plate to cool. This nomenclature is used in the application.

[0004] Part of the cooled air, flowing along the dry face of the cooling plate, is evacuated in order to cool a room: arrow D2. Another part of the cooled air is reinjected into the cooler and directed so that it flows in contact with the wet face of the cooling plate: arrow D3. The air thus reintroduced heats up, evaporating the water present on the wet face of the cooling plate: arrow D(4). This results in a drop in the temperature of the cooling plate. The heated air, laden with moisture, is then evacuated outside the room.

[0005] Compared with conventional air conditioning systems, a notable advantage of such coolers is the absence of refrigerant. These devices only need to be supplied with water. This results in a more favorable environmental balance than conventional air conditioners, which rely on the compression of a refrigerant. Refrigerants are known to have harmful effects on the environment.

[0006] Examples of indirect cooling devices have been described in WO2016134417 and WO2022184871.SUMMARY OF THE INVENTION

[0007] An important aspect of this type of device is the need to maintain a certain level of wetness, i.e., a certain amount of water, along the wet faces delimiting the wet channel, in contact with which the air can evaporate the water. The evaporation of water causes the plate to cool.

[0008] One difficulty is that as the water evaporates, it can cause fouling of the device through the deposition of particles, such as mineral salts. The accumulation of particles can lead to fouling of the device, hindering the wetting of the plates.

[0009] Prolonged wetting of the wet faces, combined with a potentially high humid air temperature, may be conducive to bacterial growth.

[0010] Another source of fouling is related to dust contained in the air to be cooled. One option is to use filters at the air intake. However, such filters need to be changed frequently to prevent clogging.

[0011] In addition to clogging, the device may suffer from aging due to contact between water and certain components of the device, such as the plates, or due to exposure to UV radiation.

[0012] A first object of the invention is an indirect evaporative cooling air conditioning device, the device being intended to blow cooled air into a room, the device comprising:

[0013] an air inlet, intended to admit air to be cooled;

[0014] a plurality of plates forming a stack, the plates being spaced apart from each other along a transverse axis, each plate comprising a dry face opposite a wet face, the wet face of each plate being configured to be wetted by water, each plate being designed to be cooled by the evaporation of water from the wet face;the device being such that, in the stack:

[0015] two adjacent plates delimit a channel, the channel being:

[0016] either a dry channel, delimited by two dry faces of two adjacent plates,

[0017] or a wet channel, delimited by two wet faces of two adjacent plates;

[0018] the plates are arranged so as to form an alternation between dry channels and wet channels, each dry channel being adjacent to a wet channel;

[0019] each dry channel extends, along a longitudinal axis, between a hot inlet, connected to the air intake, and a cold outlet, the cold outlet being intended for the evacuation of cooled air following the flow of air in the dry channel;

[0020] each wet channel extends along the longitudinal axis between a wet inlet and a wet outlet, the wet outlet being intended for the evacuation of humidified air following flow through the wet channel, the wet channel being configured to receive part of the air flowing out of the dry channel;the device being characterized in that:

[0021] the stack is held in a cooling module;

[0022] the cooling module is configured to be inserted into a base and removed from the base, the base defining a housing into which the cooling module may be inserted, the base being arranged to receive the air to be cooled and / or to evacuate the hot and humid air resulting from the stack and / or to evacuate the cooled air.

[0023] According to one possibility:

[0024] the base defines a housing, the housing being intended to be occupied by the cooling module;

[0025] the housing is configured to allow translation of the cooling module within the housing, so as to insert the cooling module into the housing or remove the cooling module from the housing.

[0026] According to one possibility, the base defines different housings, each housing being configured to be occupied by the cooling module.

[0027] According to one possibility:

[0028] the base extends between a front face and a rear face;

[0029] when the cooling module is inserted into the base, the front face and / or the rear face form a stop to define a position of the cooling module in the base.

[0030] Preferably, each wet face of a set of wet faces of wet channels is coated with a capillary structure conducive to water diffusion, by capillarity, along said wet face.

[0031] The stack may be such that:

[0032] each wet channel extends between a wet inlet and several wet outlets, distributed along the lateral axis;

[0033] the wet outlets of different wet channels are aligned parallel to the transverse axis;

[0034] the stack includes at least one sealing wall, extending opposite wet outlets aligned along the transverse axis, the sealing wall delimiting an evacuation chamber, configured to collect the humid air leaving each wet channel.

[0035] The base may comprise or be configured to be connected to a ventilation system arranged to allow air to be cooled to enter the dry channels and / or air resulting from the wet channels and / or cooled air resulting from the dry channels to be extracted.

[0036] The cooling module may include at least one support wall, the support wall being configured to rest on a seal when the cooling module is inserted into the base, the seal being disposed between the support wall and the base.

[0037] According to one possibility

[0038] the base has a front face and a rear face;

[0039] the cooling module has a front support wall and a rear support wall, such that when the cooling module is inserted into the base:

[0040] the rear support wall is pressed against the rear face;

[0041] the front support wall is pressed against the front face;

[0042] a front seal is disposed between the front support wall and the front face;

[0043] a rear seal is disposed between the rear support wall and the rear face;

[0044] so as to ensure a seal between:

[0045] (i) the cold outlets of the dry channels and an internal space, extending around the cooling module, between the front support wall and the rear support wall, and delimited by the base;

[0046] (ii) the wet outlets of the wet channels and the internal space.

[0047] The front support wall and the rear support wall may be annular and extend around the stack.

[0048] Another object of the invention is a method for cooling air in a room using a device according to the first object of the invention, comprising:

[0049] actuating the ventilation system so as to:

[0050] admitting the air to be cooled through the air intake of the device;

[0051] directing a portion of the cooled air, having flowed through a dry channel, into a wet channel;

[0052] extracting another part of the cooled air, which has flowed through the dry channel, to the room;

[0053] extracting the humid air flowing out of each wet channel to the outside of the room;

[0054] wetting the wet faces of different plates of at least one stack of the device.BRIEF DESCRIPTION OF THE DRAWINGS

[0055] FIG. 1 describes the principles of adiabatic cooling.

[0056] FIG. 2 shows an example of a plate stack, forming dry channels and wet channels.

[0057] FIG. 3A shows a dry face of a plate.

[0058] FIG. 3B shows a wet face of a plate.

[0059] FIG. 4 shows a top view of the wet face of a plate.

[0060] FIGS. 5A to 5E show an example of a plate stack. In FIGS. 5A to 5E, the outlet of each dry channel, known as dry outlet, and the inlet of each wet channel, known as wet inlet, are shown facing the viewer.

[0061] FIG. 6A shows a cooling module supporting the stacks, facing a housing it is designed to occupy in a base.

[0062] FIG. 6B shows a base defining four housings.

[0063] FIG. 6C shows the rear of a base.

[0064] FIG. 7 shows the stack schematized in FIGS. 5A to 5E. In FIG. 7, the outlet of each wet channel, known as the wet outlet, and the inlet of each dry channel, are shown facing the viewer.DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0065] FIG. 2 shows a detail of a plate stack 2 of a device that is the subject of the invention. The device is intended to blow cooled air into a room.

[0066] A room denotes any enclosure in which the air is to be cooled. The room may be a room in a building, such as a residential or industrial building, or a room in a means of transport, such as a vehicle cabin.

[0067] The geometry of the stack is similar to that described in application WO2022184871. FIG. 2 shows four plates. The stack may comprise several dozen or even hundreds of plates, for example between 30 and 1000 plates 10. The plates 10 are arranged parallel to each other, perpendicular to a transverse axis Z. Each plate 10 extends parallel to a plane PXY. Each plate extends, parallel to a longitudinal axis X, according to a length l, and, parallel to a lateral axis Y, according to a width L. The stack extends, parallel to the transverse axis Z, according to a height h. The height h depends on the number of plates. The length l, the width L, and the height h are shown in FIG. 5A. The stack is delimited by a lower plate and an upper plate.

[0068] During operation of the device, the transverse axis Z is assumed vertical (upwards), within ±30° or ±10°. This allows water to flow by gravity from the upper plate to the lower plate, as described below.

[0069] Each plate 10 has a wet face 10w and a dry face 10d. The dry and wet faces of the same plate are opposite each other, in the sense that they are separated by the thickness of the plate. The thickness of each plate, along the Z axis, is as thin as possible, taking into account mechanical strength constraints. The thickness depends on the material forming the plate. The thickness may be between 10 μm and 1 mm, or even between 10 μm and 500 μm. The invention relies on heat conduction along the Z axis through each plate 10.

[0070] The stack is such that the wet (and dry) faces of two consecutive plates face each other. Two wet faces 10w, facing each other and belonging to two adjacent plates, delimit a wet channel 20w. Two dry faces 10d, facing each other and belonging to two adjacent plates, delimit a dry channel 20d.

[0071] Each wet face 10w is intended to be wetted by water as evenly as possible.

[0072] In FIG. 2, each plate has been assigned a rank n, where n is an integer. n is incremented between two successive plates along the Z axis, in the opposite direction to the Z axis. Plates 10n, 10n+1, 10n+2, and 10n+3 are shown. Each plate has a wet face, indicated by the index w, and a dry face, indicated by the index d. The wet faces 10n,w, 10n+1,w of the respective plates 10n, 10n+1 delimit a wet channel 20w. The dry faces 10n+1,d, 10n+2,d of the respective plates 10n+1, 10n+2 delimit a dry channel 20d. The wet faces 10n+2,w, 10n+3,w of the respective plates 10n+2), 10n+3 delimit a wet channel 20w.

[0073] Thus, the stack is formed by alternating dry channels 20d and wet channels 20w. Each dry channel extends along the longitudinal axis X between a hot inlet 20d,in, through which the hot air to be cooled flows, and a cold outlet 20d,out. The ventilation system is configured to allow air to flow through the dry channels and wet channels. The cold outlet 20d,out may be connected to a cooled air outlet, configured to blow the cooled air into the room.

[0074] The air to be cooled is drawn into or blown into the device by a ventilation system, not shown in FIG. 2, through an inlet. The ventilation system comprises one or more fans. In the example shown in FIG. 2, the air to be cooled is admitted parallel to a longitudinal axis X.

[0075] The ventilation system 2 is detailed in connection with FIGS. 6A to 6C.

[0076] Each dry channel 20d is connected to an adjacent wet channel 20w by a fluidic junction 20′. Each wet channel 20w extends, along the longitudinal axis X, between the fluidic junction 20′ and a wet outlet 20w,out. The fluidic junction 20′ is located between the air inlet 20d,in and the cold outlet 20d,out, or at the cold outlet 20d,out. The fluid junction 20′ is preferably closer to the cold outlet 20d,out than to the hot inlet 20d,in. Thus, considering the direction of air flow in the dry channel, the fluid junction 20′ is located in the dry channel 20d, upstream of the cold outlet 20d,out or at the cold outlet. The device 1 is such that, under the effect of the ventilation system, part of the air flowing through a dry channel 20d is admitted into an adjacent wet channel 20w through the fluid junction 20′. The fluidic junction 20′ may be formed by a simple opening made in the plate separating the wet channel from the dry channel. In the examples shown, the fluidic junction 20′ is formed at one longitudinal end of the plate. Part of the cooled air is then drawn into at least one wet channel 20w adjacent to the dry channel 20d, at the cold outlet 20d,out

[0077] The air flow rate in the wet channel 20w is adjusted by the device's ventilation system. This is facilitated by the fact that the flow in each dry channel is preferably laminar, with the air velocity being, for example, between 0.5 m / s and 3 m / s.

[0078] The fluid junction 20′, coupled to the ventilation system, may direct 50 to 75% of the air flow flows towards the cold outlet 20d,out, while 25% to 50% of the air through the fluid junction towards the wet channel 20w. It should be noted that the air flow through each wet channel 20w represented by solid arrows in FIG. 2, is in the opposite direction to the air flow in the adjacent dry channel, which is represented by a dashed arrow in FIG. 2. The device is thus configured to operate in counterflow. The cooled air emanating from each dry channel is represented by a mixed-line arrow.

[0079] In the following figures, the legend associated with the arrows representing the flows is identical: dashed arrows for dry air, mixed dashed arrows for cooled air, and solid arrows for humid air.

[0080] The length l may be between 5 cm and 1 m, and preferably between 10 cm and 30 cm. The length l is preferably:

[0081] less than the width L, for example at least 1.5 times less, or even at least 2 times less or at least 3 times less than the width L.

[0082] and / or less than the height h, for example at least 1.5 times less, or even at least 2 times less or at least 3 times less than the height h.

[0083] Two adjacent plates 10n, 10n+1 are spaced apart from each other, parallel to the Z axis, at a distance preferably less than 2 cm, or even less than 1 cm or 0.5 cm. The spacing between two adjacent plates may preferably be between 0.5 mm and 2 mm.

[0084] FIG. 3A shows two plates 10n, 10n+1 according to a first embodiment. In FIG. 3A, the dry face 10d,n of plate 10n may be seen. The respective wet faces 10w,n and 10w,n+1 of plates 10n and 10n+1 delimit a wet channel 20w. The latter extends between a wet inlet 20w,in and a wet outlet 20w,out. Each outlet 20w,out is formed at a notch 17 made in the plates. A notch corresponds to a localized reduction in the length of the plate. Between two successive notches, along the lateral axis, two successive plates delimiting a wet channel are joined to each other, forming a wet partition 13. At each notch 17, the successive plates delimiting a wet channel 20w are spaced apart from each other so as to define an opening 13′ forming a wet outlet 20w,out. Such a configuration is described in more detail in application FR2207710.

[0085] Each plate is delimited by two lateral edges 11, 12 extending parallel to the longitudinal axis X and spaced apart from each other along the lateral axis Y. At each lateral edge 11, 12, a wet channel is delimited by a first capillary structure 21. The first capillary structure 21 is formed by a first capillary material allowing liquid diffusion, in this case water, by capillarity, as well as storage of said liquid. In this example, the liquid considered is water, which is the preferred embodiment, without excluding the possibility of using another liquid.

[0086] The term “capillary material” refers to a material that is, for example, permeable to a liquid and allows the liquid to diffuse by capillary action, which causes a capillary pumping phenomenon.

[0087] Each first capillary structure 21 extends along the entire side edge of the wet channel. The thickness of each first capillary structure, defined along the transverse axis Z, is preferably greater than 0.3 mm or 0.5 mm. Preferably, the thickness of each first capillary structure is less than 5 or 10 mm. The thickness range of 0.5 mm to 5 mm is considered optimal. Preferably, the thickness of each first capillary structure 21 is such that the first capillary structure is in contact with the two wet faces delimiting a wet channel.

[0088] The first capillary material has a capillary rise of a few centimeters. Capillary rise refers to the height at which water migrates, by capillary pumping, in the first capillary material held vertically.

[0089] FIG. 3B shows an example of a wet face 10w,n+1 of the plate 10n+1 shown in FIG. 3A. Along the lateral axis Y, each first capillary structure 21 extends over a width preferably between 1 mm and 30 mm, preferably between 3 mm and 10 mm. Each first capillary structure is intended to form a water buffer reservoir at each wet channel. The fact that each first capillary structure forms a buffer reservoir makes it possible to avoid a continuous supply of water.

[0090] In this example, each first capillary structure 21 extends along the longitudinal axis X between two opposite longitudinal ends 21X. In the example shown, water supplies each first capillary structure 21 by capillary action from each longitudinal end 21X, as indicated by the arrows F1. Migration occurs parallel to the longitudinal axis X.

[0091] The water supply to the first capillary structures belonging to adjacent wet channels is described below, in connection with FIG. 5A: the first capillary structures 21 of two adjacent wet channels, aligned along the Z axis, are in contact with each other, so as to allow water to flow from one first capillary structure to the other, the contact between said first capillary structures forming a fluidic contact (or bridge).

[0092] The wet face 10w,n+1 is coated with a second capillary structure 22, which in this case takes the form of a thin sheet. The second capillary structure 22 is arranged in contact with the plate 10n+1. The second capillary structure 22 extends from at least one first capillary structure 21. In the example shown in FIG. 3B, the second capillary structure 22 extends between the two first capillary structures 21, the latter forming the side edges of the wet channel. The thickness of the second capillary structure 22 is less than the thickness of each first capillary structure 21. Preferably, the second capillary structure 22 is at least 2 times or 3 times thinner than each first capillary structure 21. Thus, the thickness of the second capillary structure 22 is less than 1000 μm. The thickness of the second capillary structure 22 is preferably between 10 μm and a few hundred μm, for example between 10 μm and 400 μm. The second material may be a paper-type material, for example blotting paper or a nonwoven or woven material. It is sufficiently thin to allow the plate to cool under the effect of the evaporation of the water soaking the second capillary structure. However, it is sufficiently thick to allow sufficient capillary pumping.

[0093] The capillary rise of the second material is greater than the capillary rise of the first material. The capillary rise of the second material is preferably greater than 10 cm, or even greater than 20 cm or 30 cm.

[0094] Driven by capillary pumping, the water stored in each first capillary structure 21 migrates through the second capillary structure 22, along the wet face. The migration of water through each second capillary structure 22 is represented by the arrows F2.

[0095] Thus, at a wet channel, the liquid migrates:

[0096] along the longitudinal axis X, through each first capillary structure 21, starting from at least one longitudinal end 21X;

[0097] then from each first capillary structure 21, through the second capillary structure 22, along the wet face.

[0098] The amount of water evaporating from each second capillary structure is compensated by capillary pumping of the water stored in each first capillary structure. This maintains a sufficient amount of water along each wet face to allow evaporation in the wet channel. This results in cooling of the plate, allowing the air flowing in the adjacent dry channel to be cooled, according to the operating principle described in connection with FIG. 1. However, as evaporation occurs, deposits may accumulate, particularly within the second capillary structure, as described in the prior art. As results fouling builds up on each wet face.

[0099] FIG. 4 shows the wet face as described in connection with FIGS. 3A and 3B. The first two capillary structures 21, extending along the side edges 11, 12 of the plate, may be seen, as well as a second capillary structure 22, extending between the first capillary structures, along the wet face.

[0100] At each dry channel, along each notch 17, the adjacent plates delimiting the dry channel meet, forming a curved dry partition. Thus, a dry partition, enclosing a dry channel, extends between two wet outlets 20w,out of two adjacent wet channels.

[0101] Wet sealing walls 18 are applied against the plate stack 10, opposite each wet outlet. Each wet sealing wall 18 collects the wet air coming out of the different wet channels. Thus, each wet sealing wall 18 forms an evacuation chamber 20, which allows the wet air from the wet channels to be collected and conveyed in a sealed manner, opposite the dry partitions, the latter being formed at each notch.

[0102] FIG. 5A shows a stack 2 of plates 10, alternately delimiting dry channels and wet channels. The stack is supported by a frame 2′, part of which is shown in FIG. 5A. The frame 2′ and the stack form a cooling module 3.

[0103] FIG. 5B shows a detail of the stack. The first three plates 101, 102, and 103 of the stack are identified. The rank n assigned to each plate is lower when the plate is higher when the transverse axis is vertical. Plate 101 corresponds to the top plate of the stack. Each longitudinal end 21X of a first capillary structure is connected to a longitudinal end of an adjacent first capillary structure by a fluid connection, for example by simple contact. A water inlet allows the first upper capillary structure to be wetted, i.e., the first capillary structure formed at the wet channel delimited by the lowest rank plates (n=1 and 2 when the first plates delimit a wet channel, or n=2 and 3 when the first plates of rank 1 and 2 delimit a dry channel). The water migrates, by capillarity, through the first capillary structure 21, along the longitudinal axis. In addition, under the effect of gravity, the water migrates, step by step, between the successive first capillary structures. Thus, the wetting of the first capillary structures takes place:

[0104] along each first capillary structure 21, by capillarity, along the longitudinal axis X;

[0105] between the first capillary structures extending into two different wet channels, through the combined action of capillarity and gravity, along the transverse axis Z.

[0106] FIG. 5C shows the complete cooling module 3. The cooling module 3 defines water inlets 25, in the form of wells, designed to be supplied with water. Each well 25 is in fluid contact with each upper first capillary structure. Each first upper capillary structure is wetted by water flowing from the well 25 disposed vertically below said first capillary structure. The water migrates by capillarity along the first capillary structure, as well as by both of capillarity and gravity, towards the adjacent first capillary structure. The migration of water towards the various first capillary structures thus takes place by combining longitudinal diffusion and transverse diffusion.

[0107] The water inlet is connected to a water inlet coming from outside the device. Some of the water distributed at the water inlet may come from a receptacle connected to a water outlet 26.

[0108] FIG. 5D shows a detail of the upper part of the stack shown in FIG. 5C. The upper wet channel is delimited by plates 101 and 102. The well 25 is supplied with water so as to wet the first capillary structure arranged between plates 101 and 102, then, step by step, the first capillary structures arranged between plates 103 and 104, then 105 and 106 . . . .

[0109] FIG. 5E shows the lower part of the stack. An opening 26 allows excess water flowing from the first lower capillary structure, i.e., the lowest first capillary structure, to drain away. The excess water may be collected in a receptacle. A pump, not shown, is configured to recover water from the receptacle in order to feed it back into the water inlet 25. The water supply to the water inlet 25 includes water from outside the device, as well as water collected through the water outlet 26. It should be noted that the excess water collected in the receptacle has not undergone evaporation. It is therefore not concentrated in insoluble impurities, such as minerals, present in the water. It can therefore be returned to the water inlet 25 without risk of clogging the device.

[0110] Due to its thickness, which is greater than the thickness of the second capillary structures 22 with which it is in contact, each first capillary structure 21 acts as a buffer reservoir. Thus, part of the water intended for wetting the second capillary structures 22 is temporarily stored in the first capillary structures. This buffer storage function allows sequential feeding of each water inlet 25.

[0111] The arrangement of the first capillary structures 21 and the second capillary structures 22 allows for controlled wetting of each wet face delimiting the wet channels. The diffusion of water by capillarity along the wet faces maintains sufficient wetting to allow for effective cooling of the plates.

[0112] The supply to each water inlet 25 allows the water flowing in the device to be renewed. The water supply to the device may be sequential, thanks to the buffer storage function provided by the first capillary structures 21. Surplus water is collected in receptacles 26 and may be pumped to the water inlet 25. As a result, the device does not require a water drain. This facilitates its implementation by minimizing installation constraints, particularly in individual homes.

[0113] According to one possibility, the first capillary structures 21 and the second capillary structures 22 are made of the same capillary material. In other words, the first capillary material is identical to the second capillary material. Preferably, at the side edges, the thickness of the capillary material is greater than its thickness along the wet faces. This allows a controlled level of humidity to be maintained along each wet face. According to this possibility, the first capillary structure is formed by a first thickness of capillary material. The second capillary structure is formed by a second thickness of capillary material, which is less than the first thickness.

[0114] According to one possibility, the second capillary structure is formed by structuring each wet face, for example by providing channels configured to allow capillary pumping.

[0115] Regardless of the method of implementation, at least one wet face, or even each wet face delimiting at least one wet channel, comprises a capillary structure allowing, by capillary pumping, a quantity of water to be maintained as uniformly as possible and as constantly as possible along said wet face.

[0116] As mentioned in the prior art, under the effect of water evaporation, solid particles, for example mineral salts, may accumulate in the capillary structure deposited along each wet face. Such accumulation may compromise the uniform distribution of moisture along the wet faces. Given the thinness of the wet channels, generally a few millimeters, it is not feasible to replace individual plates.

[0117] The design of the device addresses this constraint. As shown in FIGS. 6A and 6C, the plate stack is supported by frame 2′. The cooling module 3 is configured to be inserted into a base 4. The base 4 is shown in FIGS. 6A to 6C. The base 4 refers to a structure, preferably fixed, arranged to receive the air to be cooled and to evacuate the hot, humid air resulting from each stack. The base 4 is connected to the ventilation system 6. In the example shown, the ventilation system 6 comprises a first fan 61, allowing air to be cooled to be admitted into the device 1. The base 4 comprises a second fan 62, shown in FIG. 6C, configured to evacuate the humid air coming out of the humid channels and evacuation chambers 20.

[0118] The base 4 defines at least one housing 5. A housing is a hollow cavity into which a cooling module 3, supporting a plate stack 2, may be inserted. In the example described in connection with FIGS. 6A to 6C, the base defines four different housings, each housing being distinct from the others. Thus, the base can accommodate four different modules. The base includes the ventilation system 6 or is configured to be connected to the ventilation system 6.

[0119] The base 4 extends between a rear face 4r and a front face 4a. The front face and rear face form faces on which the cooling module rests when inserted into the base. The front and rear faces extend from an annular envelope 4c, extending around each housing intended to receive a cooling module. The front and rear faces form stops for defining the position of the cooling module in the housing 5.

[0120] The cooling module 3 is inserted into the base 4 by translation. In the example shown in FIGS. 6A to 6C, the cooling module 3 is translated into the base 4 by sliding on slides 9. These slides are arranged parallel to the longitudinal axis X, on either side of the housing intended to be occupied by the cooling module. The slides are provided in the base. The front and rear faces act as stops that block the translation of the cooling module.

[0121] In other configurations, the cooling module 3 is moved parallel to the transverse axis Z or parallel to the lateral axis Y.

[0122] FIG. 7 shows a view of the cooling module 3 facing the hot inlets 20d,in of the dry channels 20d. The hot inlets 20d,in are designed to receive the air to be cooled, which comes from the air intake of the device. At each hot inlet 20d,in, the plates delimiting each dry channel 20d are spaced apart from each other so as to form an opening 15′. Between each opening 15′, a dry partition is provided along the indentations 17 by contact between the plates delimiting the dry channel.

[0123] When the cooling module is inserted into the base 4, the hot inlets 20d,in are located near the rear face 4r of the base 4. The hot, humid air coming out of the wet outlets 20w,out is collected by the second fan 62 to be expelled outside the room to be cooled. The cold outlet 20d,out of each dry channel 20d is located near the front face 4a, so as to blow the cooled air into the room.

[0124] In order to maintain a seal between the cooled air and the hot air to be cooled, a front seal 7a and a rear seal 7r are interposed between the cooling module 3 and the base 4, respectively at the front face 4a and the rear face 4r. The front and rear seals are shown in FIG. 6B. On the cooling module 3, a front support surface 8a and a rear support surface 8r. rest respectively on the front seal 7a and the rear seal 7r when the cooling module is inserted into the base 4. Thus, when the cooling module is inserted into the base 4:

[0125] the front seal 7a is interposed between the front support surface 8a of the cooling module and the front face 4a of the base;

[0126] the rear seal 7r is interposed between the rear support surface 8r of the cooling module and the rear face 4r of the base

[0127] Prior to inserting the cooling module into the base, each seal is attached either to the base or to the cooling module.

[0128] Thus, when the cooling module is inserted into the base:

[0129] the front face is located near the cold outlet of various dry channels;

[0130] the rear face is located near the hot inlet of the various dry channels;

[0131] the front face extends between the cold outlet of the dry channels and the rear face;

[0132] the rear face extends between the hot inlet of the dry channels and the front face;

[0133] the front support wall 8a rests on the front face 4a;

[0134] the rear support wall 8r rests on the rear face 4r

[0135] so as to ensure a seal between:

[0136] the cold outlet of the dry channels 20d and an internal space, extending around the stack 2, between the front face 4a and the rear face, and delimited by the envelope 4c formed by the base, around the stack. The internal space is occupied by humidified air flowing out of the evacuation chambers 20, before being evacuated outside the room to be cooled by the second fan 62. The internal space extends between the cooling module and the base, being delimited by the front support wall and the rear support wall. It acts as a collector for the humidified air flowing out of the evacuation chambers 20, upstream of the second fan 62. The term “upstream” is to be interpreted according to the direction of air flow during operation of the device,

[0137] the hot inlet 20d,in of the dry channels and the internal space.

[0138] The front support wall 8a and the rear support wall 8r are preferably annular: they form a contour around the stack held in the frame.

[0139] The cooling module may be secured in the base 4 by fastening means 9′, for example screws or nuts. The fastening means are reversible, so as to allow simple, manual removal of the cooling module 3 from the base 4.

[0140] An important aspect of the invention is that the cooling module 3, comprising the plates 10, may be easily removed from the base 4 to be replaced with a new cooling module. The cooling module 3 is replaced regularly when the risk of fouling of the wet channels is considered to be high, or when aging due to the effect of water or exposure to UV radiation is too pronounced. The cooling module may be replaced every 2 or 3 years, or every 5 years, for example. All or part of the removed cooling module may be recycled.

[0141] The device has a modular design, with each cooling module 3 able to be inserted into a base 4. The number of housings 5 formed in a base, and therefore the number of cooling modules it can accommodate, depends on the required cooling capacity. The modular design simplifies the manufacture of the device, as the same cooling module may be inserted into bases of different shapes, dedicated to different applications: domestic application, application in industrial buildings, or application in a means of transport.

[0142] Another notable advantage is that the base 4 and each cooling module 3 may be handled independently of each other. This limits the mass of the components to be handled, particularly during installation. Preferably, during installation, the base is fixed to a host structure, for example a civil engineering structure. The cooling modules are then inserted one after the other into the base.

[0143] Preferably, the base 4 is configured so that the ventilation system 6 can simultaneously address different cooling modules. Thus, the first fan and the second fan allow hot air to be admitted into several cooling modules and / or hot and humidified air to be extracted from said cooling modules.

Examples

Embodiment Construction

[0065]FIG. 2 shows a detail of a plate stack 2 of a device that is the subject of the invention. The device is intended to blow cooled air into a room.

[0066]A room denotes any enclosure in which the air is to be cooled. The room may be a room in a building, such as a residential or industrial building, or a room in a means of transport, such as a vehicle cabin.

[0067]The geometry of the stack is similar to that described in application WO2022184871. FIG. 2 shows four plates. The stack may comprise several dozen or even hundreds of plates, for example between 30 and 1000 plates 10. The plates 10 are arranged parallel to each other, perpendicular to a transverse axis Z. Each plate 10 extends parallel to a plane PXY. Each plate extends, parallel to a longitudinal axis X, according to a length l, and, parallel to a lateral axis Y, according to a width L. The stack extends, parallel to the transverse axis Z, according to a height h. The height h depends on the number of plates. The length...

TECHNICAL FIELD

[0001] The technical field of the invention is an air cooling device using indirect evaporative cooling.BACKGROUND ART

[0002] Air coolers using indirect evaporative cooling, also known as indirect adiabatic dew point coolers, have been known for several decades.

[0003] The principle of such coolers is illustrated in FIG. 1. It is based on the use of an evaporative heat exchanger, in which the incoming air (arrow D1 shown as a dotted line in FIG. 1) is cooled, without humidification, potentially to its dew point. Cooling occurs by air flows along a cooling plate P1, which is cooled by water evaporation. The cooling plate has a dry face, in contact with which the air to be cooled flows, and a wet face, moistened by water, the water being symbolized by circles in FIG. 1. In FIG. 1, the dashed arrow corresponds to the air to be cooled, the mixed dashed arrow represents the cooled air or air in the process of being cooled, and the solid arrow corresponds to the air flowing in the wet channel, the evaporation of which causes the plate to cool. This nomenclature is used in the application.

[0004] Part of the cooled air, flowing along the dry face of the cooling plate, is evacuated in order to cool a room: arrow D2. Another part of the cooled air is reinjected into the cooler and directed so that it flows in contact with the wet face of the cooling plate: arrow D3. The air thus reintroduced heats up, evaporating the water present on the wet face of the cooling plate: arrow D(4). This results in a drop in the temperature of the cooling plate. The heated air, laden with moisture, is then evacuated outside the room.

[0005] Compared with conventional air conditioning systems, a notable advantage of such coolers is the absence of refrigerant. These devices only need to be supplied with water. This results in a more favorable environmental balance than conventional air conditioners, which rely on the compression of a refrigerant. Refrigerants are known to have harmful effects on the environment.

[0006] Examples of indirect cooling devices have been described in WO2016134417 and WO2022184871.SUMMARY OF THE INVENTION

[0007] An important aspect of this type of device is the need to maintain a certain level of wetness, i.e., a certain amount of water, along the wet faces delimiting the wet channel, in contact with which the air can evaporate the water. The evaporation of water causes the plate to cool.

[0008] One difficulty is that as the water evaporates, it can cause fouling of the device through the deposition of particles, such as mineral salts. The accumulation of particles can lead to fouling of the device, hindering the wetting of the plates.

[0009] Prolonged wetting of the wet faces, combined with a potentially high humid air temperature, may be conducive to bacterial growth.

[0010] Another source of fouling is related to dust contained in the air to be cooled. One option is to use filters at the air intake. However, such filters need to be changed frequently to prevent clogging.

[0011] In addition to clogging, the device may suffer from aging due to contact between water and certain components of the device, such as the plates, or due to exposure to UV radiation.

[0012] A first object of the invention is an indirect evaporative cooling air conditioning device, the device being intended to blow cooled air into a room, the device comprising:

[0013] an air inlet, intended to admit air to be cooled;

[0014] a plurality of plates forming a stack, the plates being spaced apart from each other along a transverse axis, each plate comprising a dry face opposite a wet face, the wet face of each plate being configured to be wetted by water, each plate being designed to be cooled by the evaporation of water from the wet face;the device being such that, in the stack:

[0015] two adjacent plates delimit a channel, the channel being:

[0016] either a dry channel, delimited by two dry faces of two adjacent plates,

[0017] or a wet channel, delimited by two wet faces of two adjacent plates;

[0018] the plates are arranged so as to form an alternation between dry channels and wet channels, each dry channel being adjacent to a wet channel;

[0019] each dry channel extends, along a longitudinal axis, between a hot inlet, connected to the air intake, and a cold outlet, the cold outlet being intended for the evacuation of cooled air following the flow of air in the dry channel;

[0020] each wet channel extends along the longitudinal axis between a wet inlet and a wet outlet, the wet outlet being intended for the evacuation of humidified air following flow through the wet channel, the wet channel being configured to receive part of the air flowing out of the dry channel;the device being characterized in that:

[0021] the stack is held in a cooling module;

[0022] the cooling module is configured to be inserted into a base and removed from the base, the base defining a housing into which the cooling module may be inserted, the base being arranged to receive the air to be cooled and / or to evacuate the hot and humid air resulting from the stack and / or to evacuate the cooled air.

[0023] According to one possibility:

[0024] the base defines a housing, the housing being intended to be occupied by the cooling module;

[0025] the housing is configured to allow translation of the cooling module within the housing, so as to insert the cooling module into the housing or remove the cooling module from the housing.

[0026] According to one possibility, the base defines different housings, each housing being configured to be occupied by the cooling module.

[0027] According to one possibility:

[0028] the base extends between a front face and a rear face;

[0029] when the cooling module is inserted into the base, the front face and / or the rear face form a stop to define a position of the cooling module in the base.

[0030] Preferably, each wet face of a set of wet faces of wet channels is coated with a capillary structure conducive to water diffusion, by capillarity, along said wet face.

[0031] The stack may be such that:

[0032] each wet channel extends between a wet inlet and several wet outlets, distributed along the lateral axis;

[0033] the wet outlets of different wet channels are aligned parallel to the transverse axis;

[0034] the stack includes at least one sealing wall, extending opposite wet outlets aligned along the transverse axis, the sealing wall delimiting an evacuation chamber, configured to collect the humid air leaving each wet channel.

[0035] The base may comprise or be configured to be connected to a ventilation system arranged to allow air to be cooled to enter the dry channels and / or air resulting from the wet channels and / or cooled air resulting from the dry channels to be extracted.

[0036] The cooling module may include at least one support wall, the support wall being configured to rest on a seal when the cooling module is inserted into the base, the seal being disposed between the support wall and the base.

[0037] According to one possibility

[0038] the base has a front face and a rear face;

[0039] the cooling module has a front support wall and a rear support wall, such that when the cooling module is inserted into the base:

[0040] the rear support wall is pressed against the rear face;

[0041] the front support wall is pressed against the front face;

[0042] a front seal is disposed between the front support wall and the front face;

[0043] a rear seal is disposed between the rear support wall and the rear face;

[0044] so as to ensure a seal between:

[0045] (i) the cold outlets of the dry channels and an internal space, extending around the cooling module, between the front support wall and the rear support wall, and delimited by the base;

[0046] (ii) the wet outlets of the wet channels and the internal space.

[0047] The front support wall and the rear support wall may be annular and extend around the stack.

[0048] Another object of the invention is a method for cooling air in a room using a device according to the first object of the invention, comprising:

[0049] actuating the ventilation system so as to:

[0050] admitting the air to be cooled through the air intake of the device;

[0051] directing a portion of the cooled air, having flowed through a dry channel, into a wet channel;

[0052] extracting another part of the cooled air, which has flowed through the dry channel, to the room;

[0053] extracting the humid air flowing out of each wet channel to the outside of the room;

[0054] wetting the wet faces of different plates of at least one stack of the device.BRIEF DESCRIPTION OF THE DRAWINGS

[0055] FIG. 1 describes the principles of adiabatic cooling.

[0056] FIG. 2 shows an example of a plate stack, forming dry channels and wet channels.

[0057] FIG. 3A shows a dry face of a plate.

[0058] FIG. 3B shows a wet face of a plate.

[0059] FIG. 4 shows a top view of the wet face of a plate.

[0060] FIGS. 5A to 5E show an example of a plate stack. In FIGS. 5A to 5E, the outlet of each dry channel, known as dry outlet, and the inlet of each wet channel, known as wet inlet, are shown facing the viewer.

[0061] FIG. 6A shows a cooling module supporting the stacks, facing a housing it is designed to occupy in a base.

[0062] FIG. 6B shows a base defining four housings.

[0063] FIG. 6C shows the rear of a base.

[0064] FIG. 7 shows the stack schematized in FIGS. 5A to 5E. In FIG. 7, the outlet of each wet channel, known as the wet outlet, and the inlet of each dry channel, are shown facing the viewer.DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0065] FIG. 2 shows a detail of a plate stack 2 of a device that is the subject of the invention. The device is intended to blow cooled air into a room.

[0066] A room denotes any enclosure in which the air is to be cooled. The room may be a room in a building, such as a residential or industrial building, or a room in a means of transport, such as a vehicle cabin.

[0067] The geometry of the stack is similar to that described in application WO2022184871. FIG. 2 shows four plates. The stack may comprise several dozen or even hundreds of plates, for example between 30 and 1000 plates 10. The plates 10 are arranged parallel to each other, perpendicular to a transverse axis Z. Each plate 10 extends parallel to a plane PXY. Each plate extends, parallel to a longitudinal axis X, according to a length l, and, parallel to a lateral axis Y, according to a width L. The stack extends, parallel to the transverse axis Z, according to a height h. The height h depends on the number of plates. The length l, the width L, and the height h are shown in FIG. 5A. The stack is delimited by a lower plate and an upper plate.

[0068] During operation of the device, the transverse axis Z is assumed vertical (upwards), within ±30° or ±10°. This allows water to flow by gravity from the upper plate to the lower plate, as described below.

[0069] Each plate 10 has a wet face 10w and a dry face 10d. The dry and wet faces of the same plate are opposite each other, in the sense that they are separated by the thickness of the plate. The thickness of each plate, along the Z axis, is as thin as possible, taking into account mechanical strength constraints. The thickness depends on the material forming the plate. The thickness may be between 10 μm and 1 mm, or even between 10 μm and 500 μm. The invention relies on heat conduction along the Z axis through each plate 10.

[0070] The stack is such that the wet (and dry) faces of two consecutive plates face each other. Two wet faces 10w, facing each other and belonging to two adjacent plates, delimit a wet channel 20w. Two dry faces 10d, facing each other and belonging to two adjacent plates, delimit a dry channel 20d.

[0071] Each wet face 10w is intended to be wetted by water as evenly as possible.

[0072] In FIG. 2, each plate has been assigned a rank n, where n is an integer. n is incremented between two successive plates along the Z axis, in the opposite direction to the Z axis. Plates 10n, 10n+1, 10n+2, and 10n+3 are shown. Each plate has a wet face, indicated by the index w, and a dry face, indicated by the index d. The wet faces 10n,w, 10n+1,w of the respective plates 10n, 10n+1 delimit a wet channel 20w. The dry faces 10n+1,d, 10n+2,d of the respective plates 10n+1, 10n+2 delimit a dry channel 20d. The wet faces 10n+2,w, 10n+3,w of the respective plates 10n+2), 10n+3 delimit a wet channel 20w.

[0073] Thus, the stack is formed by alternating dry channels 20d and wet channels 20w. Each dry channel extends along the longitudinal axis X between a hot inlet 20d,in, through which the hot air to be cooled flows, and a cold outlet 20d,out. The ventilation system is configured to allow air to flow through the dry channels and wet channels. The cold outlet 20d,out may be connected to a cooled air outlet, configured to blow the cooled air into the room.

[0074] The air to be cooled is drawn into or blown into the device by a ventilation system, not shown in FIG. 2, through an inlet. The ventilation system comprises one or more fans. In the example shown in FIG. 2, the air to be cooled is admitted parallel to a longitudinal axis X.

[0075] The ventilation system 2 is detailed in connection with FIGS. 6A to 6C.

[0076] Each dry channel 20d is connected to an adjacent wet channel 20w by a fluidic junction 20′. Each wet channel 20w extends, along the longitudinal axis X, between the fluidic junction 20′ and a wet outlet 20w,out. The fluidic junction 20′ is located between the air inlet 20d,in and the cold outlet 20d,out, or at the cold outlet 20d,out. The fluid junction 20′ is preferably closer to the cold outlet 20d,out than to the hot inlet 20d,in. Thus, considering the direction of air flow in the dry channel, the fluid junction 20′ is located in the dry channel 20d, upstream of the cold outlet 20d,out or at the cold outlet. The device 1 is such that, under the effect of the ventilation system, part of the air flowing through a dry channel 20d is admitted into an adjacent wet channel 20w through the fluid junction 20′. The fluidic junction 20′ may be formed by a simple opening made in the plate separating the wet channel from the dry channel. In the examples shown, the fluidic junction 20′ is formed at one longitudinal end of the plate. Part of the cooled air is then drawn into at least one wet channel 20w adjacent to the dry channel 20d, at the cold outlet 20d,out

[0077] The air flow rate in the wet channel 20w is adjusted by the device's ventilation system. This is facilitated by the fact that the flow in each dry channel is preferably laminar, with the air velocity being, for example, between 0.5 m / s and 3 m / s.

[0078] The fluid junction 20′, coupled to the ventilation system, may direct 50 to 75% of the air flow flows towards the cold outlet 20d,out, while 25% to 50% of the air through the fluid junction towards the wet channel 20w. It should be noted that the air flow through each wet channel 20w represented by solid arrows in FIG. 2, is in the opposite direction to the air flow in the adjacent dry channel, which is represented by a dashed arrow in FIG. 2. The device is thus configured to operate in counterflow. The cooled air emanating from each dry channel is represented by a mixed-line arrow.

[0079] In the following figures, the legend associated with the arrows representing the flows is identical: dashed arrows for dry air, mixed dashed arrows for cooled air, and solid arrows for humid air.

[0080] The length l may be between 5 cm and 1 m, and preferably between 10 cm and 30 cm. The length l is preferably:

[0081] less than the width L, for example at least 1.5 times less, or even at least 2 times less or at least 3 times less than the width L.

[0082] and / or less than the height h, for example at least 1.5 times less, or even at least 2 times less or at least 3 times less than the height h.

[0083] Two adjacent plates 10n, 10n+1 are spaced apart from each other, parallel to the Z axis, at a distance preferably less than 2 cm, or even less than 1 cm or 0.5 cm. The spacing between two adjacent plates may preferably be between 0.5 mm and 2 mm.

[0084] FIG. 3A shows two plates 10n, 10n+1 according to a first embodiment. In FIG. 3A, the dry face 10d,n of plate 10n may be seen. The respective wet faces 10w,n and 10w,n+1 of plates 10n and 10n+1 delimit a wet channel 20w. The latter extends between a wet inlet 20w,in and a wet outlet 20w,out. Each outlet 20w,out is formed at a notch 17 made in the plates. A notch corresponds to a localized reduction in the length of the plate. Between two successive notches, along the lateral axis, two successive plates delimiting a wet channel are joined to each other, forming a wet partition 13. At each notch 17, the successive plates delimiting a wet channel 20w are spaced apart from each other so as to define an opening 13′ forming a wet outlet 20w,out. Such a configuration is described in more detail in application FR2207710.

[0085] Each plate is delimited by two lateral edges 11, 12 extending parallel to the longitudinal axis X and spaced apart from each other along the lateral axis Y. At each lateral edge 11, 12, a wet channel is delimited by a first capillary structure 21. The first capillary structure 21 is formed by a first capillary material allowing liquid diffusion, in this case water, by capillarity, as well as storage of said liquid. In this example, the liquid considered is water, which is the preferred embodiment, without excluding the possibility of using another liquid.

[0086] The term “capillary material” refers to a material that is, for example, permeable to a liquid and allows the liquid to diffuse by capillary action, which causes a capillary pumping phenomenon.

[0087] Each first capillary structure 21 extends along the entire side edge of the wet channel. The thickness of each first capillary structure, defined along the transverse axis Z, is preferably greater than 0.3 mm or 0.5 mm. Preferably, the thickness of each first capillary structure is less than 5 or 10 mm. The thickness range of 0.5 mm to 5 mm is considered optimal. Preferably, the thickness of each first capillary structure 21 is such that the first capillary structure is in contact with the two wet faces delimiting a wet channel.

[0088] The first capillary material has a capillary rise of a few centimeters. Capillary rise refers to the height at which water migrates, by capillary pumping, in the first capillary material held vertically.

[0089] FIG. 3B shows an example of a wet face 10w,n+1 of the plate 10n+1 shown in FIG. 3A. Along the lateral axis Y, each first capillary structure 21 extends over a width preferably between 1 mm and 30 mm, preferably between 3 mm and 10 mm. Each first capillary structure is intended to form a water buffer reservoir at each wet channel. The fact that each first capillary structure forms a buffer reservoir makes it possible to avoid a continuous supply of water.

[0090] In this example, each first capillary structure 21 extends along the longitudinal axis X between two opposite longitudinal ends 21X. In the example shown, water supplies each first capillary structure 21 by capillary action from each longitudinal end 21X, as indicated by the arrows F1. Migration occurs parallel to the longitudinal axis X.

[0091] The water supply to the first capillary structures belonging to adjacent wet channels is described below, in connection with FIG. 5A: the first capillary structures 21 of two adjacent wet channels, aligned along the Z axis, are in contact with each other, so as to allow water to flow from one first capillary structure to the other, the contact between said first capillary structures forming a fluidic contact (or bridge).

[0092] The wet face 10w,n+1 is coated with a second capillary structure 22, which in this case takes the form of a thin sheet. The second capillary structure 22 is arranged in contact with the plate 10n+1. The second capillary structure 22 extends from at least one first capillary structure 21. In the example shown in FIG. 3B, the second capillary structure 22 extends between the two first capillary structures 21, the latter forming the side edges of the wet channel. The thickness of the second capillary structure 22 is less than the thickness of each first capillary structure 21. Preferably, the second capillary structure 22 is at least 2 times or 3 times thinner than each first capillary structure 21. Thus, the thickness of the second capillary structure 22 is less than 1000 μm. The thickness of the second capillary structure 22 is preferably between 10 μm and a few hundred μm, for example between 10 μm and 400 μm. The second material may be a paper-type material, for example blotting paper or a nonwoven or woven material. It is sufficiently thin to allow the plate to cool under the effect of the evaporation of the water soaking the second capillary structure. However, it is sufficiently thick to allow sufficient capillary pumping.

[0093] The capillary rise of the second material is greater than the capillary rise of the first material. The capillary rise of the second material is preferably greater than 10 cm, or even greater than 20 cm or 30 cm.

[0094] Driven by capillary pumping, the water stored in each first capillary structure 21 migrates through the second capillary structure 22, along the wet face. The migration of water through each second capillary structure 22 is represented by the arrows F2.

[0095] Thus, at a wet channel, the liquid migrates:

[0096] along the longitudinal axis X, through each first capillary structure 21, starting from at least one longitudinal end 21X;

[0097] then from each first capillary structure 21, through the second capillary structure 22, along the wet face.

[0098] The amount of water evaporating from each second capillary structure is compensated by capillary pumping of the water stored in each first capillary structure. This maintains a sufficient amount of water along each wet face to allow evaporation in the wet channel. This results in cooling of the plate, allowing the air flowing in the adjacent dry channel to be cooled, according to the operating principle described in connection with FIG. 1. However, as evaporation occurs, deposits may accumulate, particularly within the second capillary structure, as described in the prior art. As results fouling builds up on each wet face.

[0099] FIG. 4 shows the wet face as described in connection with FIGS. 3A and 3B. The first two capillary structures 21, extending along the side edges 11, 12 of the plate, may be seen, as well as a second capillary structure 22, extending between the first capillary structures, along the wet face.

[0100] At each dry channel, along each notch 17, the adjacent plates delimiting the dry channel meet, forming a curved dry partition. Thus, a dry partition, enclosing a dry channel, extends between two wet outlets 20w,out of two adjacent wet channels.

[0101] Wet sealing walls 18 are applied against the plate stack 10, opposite each wet outlet. Each wet sealing wall 18 collects the wet air coming out of the different wet channels. Thus, each wet sealing wall 18 forms an evacuation chamber 20, which allows the wet air from the wet channels to be collected and conveyed in a sealed manner, opposite the dry partitions, the latter being formed at each notch.

[0102] FIG. 5A shows a stack 2 of plates 10, alternately delimiting dry channels and wet channels. The stack is supported by a frame 2′, part of which is shown in FIG. 5A. The frame 2′ and the stack form a cooling module 3.

[0103] FIG. 5B shows a detail of the stack. The first three plates 101, 102, and 103 of the stack are identified. The rank n assigned to each plate is lower when the plate is higher when the transverse axis is vertical. Plate 101 corresponds to the top plate of the stack. Each longitudinal end 21X of a first capillary structure is connected to a longitudinal end of an adjacent first capillary structure by a fluid connection, for example by simple contact. A water inlet allows the first upper capillary structure to be wetted, i.e., the first capillary structure formed at the wet channel delimited by the lowest rank plates (n=1 and 2 when the first plates delimit a wet channel, or n=2 and 3 when the first plates of rank 1 and 2 delimit a dry channel). The water migrates, by capillarity, through the first capillary structure 21, along the longitudinal axis. In addition, under the effect of gravity, the water migrates, step by step, between the successive first capillary structures. Thus, the wetting of the first capillary structures takes place:

[0104] along each first capillary structure 21, by capillarity, along the longitudinal axis X;

[0105] between the first capillary structures extending into two different wet channels, through the combined action of capillarity and gravity, along the transverse axis Z.

[0106] FIG. 5C shows the complete cooling module 3. The cooling module 3 defines water inlets 25, in the form of wells, designed to be supplied with water. Each well 25 is in fluid contact with each upper first capillary structure. Each first upper capillary structure is wetted by water flowing from the well 25 disposed vertically below said first capillary structure. The water migrates by capillarity along the first capillary structure, as well as by both of capillarity and gravity, towards the adjacent first capillary structure. The migration of water towards the various first capillary structures thus takes place by combining longitudinal diffusion and transverse diffusion.

[0107] The water inlet is connected to a water inlet coming from outside the device. Some of the water distributed at the water inlet may come from a receptacle connected to a water outlet 26.

[0108] FIG. 5D shows a detail of the upper part of the stack shown in FIG. 5C. The upper wet channel is delimited by plates 101 and 102. The well 25 is supplied with water so as to wet the first capillary structure arranged between plates 101 and 102, then, step by step, the first capillary structures arranged between plates 103 and 104, then 105 and 106 . . . .

[0109] FIG. 5E shows the lower part of the stack. An opening 26 allows excess water flowing from the first lower capillary structure, i.e., the lowest first capillary structure, to drain away. The excess water may be collected in a receptacle. A pump, not shown, is configured to recover water from the receptacle in order to feed it back into the water inlet 25. The water supply to the water inlet 25 includes water from outside the device, as well as water collected through the water outlet 26. It should be noted that the excess water collected in the receptacle has not undergone evaporation. It is therefore not concentrated in insoluble impurities, such as minerals, present in the water. It can therefore be returned to the water inlet 25 without risk of clogging the device.

[0110] Due to its thickness, which is greater than the thickness of the second capillary structures 22 with which it is in contact, each first capillary structure 21 acts as a buffer reservoir. Thus, part of the water intended for wetting the second capillary structures 22 is temporarily stored in the first capillary structures. This buffer storage function allows sequential feeding of each water inlet 25.

[0111] The arrangement of the first capillary structures 21 and the second capillary structures 22 allows for controlled wetting of each wet face delimiting the wet channels. The diffusion of water by capillarity along the wet faces maintains sufficient wetting to allow for effective cooling of the plates.

[0112] The supply to each water inlet 25 allows the water flowing in the device to be renewed. The water supply to the device may be sequential, thanks to the buffer storage function provided by the first capillary structures 21. Surplus water is collected in receptacles 26 and may be pumped to the water inlet 25. As a result, the device does not require a water drain. This facilitates its implementation by minimizing installation constraints, particularly in individual homes.

[0113] According to one possibility, the first capillary structures 21 and the second capillary structures 22 are made of the same capillary material. In other words, the first capillary material is identical to the second capillary material. Preferably, at the side edges, the thickness of the capillary material is greater than its thickness along the wet faces. This allows a controlled level of humidity to be maintained along each wet face. According to this possibility, the first capillary structure is formed by a first thickness of capillary material. The second capillary structure is formed by a second thickness of capillary material, which is less than the first thickness.

[0114] According to one possibility, the second capillary structure is formed by structuring each wet face, for example by providing channels configured to allow capillary pumping.

[0115] Regardless of the method of implementation, at least one wet face, or even each wet face delimiting at least one wet channel, comprises a capillary structure allowing, by capillary pumping, a quantity of water to be maintained as uniformly as possible and as constantly as possible along said wet face.

[0116] As mentioned in the prior art, under the effect of water evaporation, solid particles, for example mineral salts, may accumulate in the capillary structure deposited along each wet face. Such accumulation may compromise the uniform distribution of moisture along the wet faces. Given the thinness of the wet channels, generally a few millimeters, it is not feasible to replace individual plates.

[0117] The design of the device addresses this constraint. As shown in FIGS. 6A and 6C, the plate stack is supported by frame 2′. The cooling module 3 is configured to be inserted into a base 4. The base 4 is shown in FIGS. 6A to 6C. The base 4 refers to a structure, preferably fixed, arranged to receive the air to be cooled and to evacuate the hot, humid air resulting from each stack. The base 4 is connected to the ventilation system 6. In the example shown, the ventilation system 6 comprises a first fan 61, allowing air to be cooled to be admitted into the device 1. The base 4 comprises a second fan 62, shown in FIG. 6C, configured to evacuate the humid air coming out of the humid channels and evacuation chambers 20.

[0118] The base 4 defines at least one housing 5. A housing is a hollow cavity into which a cooling module 3, supporting a plate stack 2, may be inserted. In the example described in connection with FIGS. 6A to 6C, the base defines four different housings, each housing being distinct from the others. Thus, the base can accommodate four different modules. The base includes the ventilation system 6 or is configured to be connected to the ventilation system 6.

[0119] The base 4 extends between a rear face 4r and a front face 4a. The front face and rear face form faces on which the cooling module rests when inserted into the base. The front and rear faces extend from an annular envelope 4c, extending around each housing intended to receive a cooling module. The front and rear faces form stops for defining the position of the cooling module in the housing 5.

[0120] The cooling module 3 is inserted into the base 4 by translation. In the example shown in FIGS. 6A to 6C, the cooling module 3 is translated into the base 4 by sliding on slides 9. These slides are arranged parallel to the longitudinal axis X, on either side of the housing intended to be occupied by the cooling module. The slides are provided in the base. The front and rear faces act as stops that block the translation of the cooling module.

[0121] In other configurations, the cooling module 3 is moved parallel to the transverse axis Z or parallel to the lateral axis Y.

[0122] FIG. 7 shows a view of the cooling module 3 facing the hot inlets 20d,in of the dry channels 20d. The hot inlets 20d,in are designed to receive the air to be cooled, which comes from the air intake of the device. At each hot inlet 20d,in, the plates delimiting each dry channel 20d are spaced apart from each other so as to form an opening 15′. Between each opening 15′, a dry partition is provided along the indentations 17 by contact between the plates delimiting the dry channel.

[0123] When the cooling module is inserted into the base 4, the hot inlets 20d,in are located near the rear face 4r of the base 4. The hot, humid air coming out of the wet outlets 20w,out is collected by the second fan 62 to be expelled outside the room to be cooled. The cold outlet 20d,out of each dry channel 20d is located near the front face 4a, so as to blow the cooled air into the room.

[0124] In order to maintain a seal between the cooled air and the hot air to be cooled, a front seal 7a and a rear seal 7r are interposed between the cooling module 3 and the base 4, respectively at the front face 4a and the rear face 4r. The front and rear seals are shown in FIG. 6B. On the cooling module 3, a front support surface 8a and a rear support surface 8r. rest respectively on the front seal 7a and the rear seal 7r when the cooling module is inserted into the base 4. Thus, when the cooling module is inserted into the base 4:

[0125] the front seal 7a is interposed between the front support surface 8a of the cooling module and the front face 4a of the base;

[0126] the rear seal 7r is interposed between the rear support surface 8r of the cooling module and the rear face 4r of the base

[0127] Prior to inserting the cooling module into the base, each seal is attached either to the base or to the cooling module.

[0128] Thus, when the cooling module is inserted into the base:

[0129] the front face is located near the cold outlet of various dry channels;

[0130] the rear face is located near the hot inlet of the various dry channels;

[0131] the front face extends between the cold outlet of the dry channels and the rear face;

[0132] the rear face extends between the hot inlet of the dry channels and the front face;

[0133] the front support wall 8a rests on the front face 4a;

[0134] the rear support wall 8r rests on the rear face 4r

[0135] so as to ensure a seal between:

[0136] the cold outlet of the dry channels 20d and an internal space, extending around the stack 2, between the front face 4a and the rear face, and delimited by the envelope 4c formed by the base, around the stack. The internal space is occupied by humidified air flowing out of the evacuation chambers 20, before being evacuated outside the room to be cooled by the second fan 62. The internal space extends between the cooling module and the base, being delimited by the front support wall and the rear support wall. It acts as a collector for the humidified air flowing out of the evacuation chambers 20, upstream of the second fan 62. The term “upstream” is to be interpreted according to the direction of air flow during operation of the device,

[0137] the hot inlet 20d,in of the dry channels and the internal space.

[0138] The front support wall 8a and the rear support wall 8r are preferably annular: they form a contour around the stack held in the frame.

[0139] The cooling module may be secured in the base 4 by fastening means 9′, for example screws or nuts. The fastening means are reversible, so as to allow simple, manual removal of the cooling module 3 from the base 4.

[0140] An important aspect of the invention is that the cooling module 3, comprising the plates 10, may be easily removed from the base 4 to be replaced with a new cooling module. The cooling module 3 is replaced regularly when the risk of fouling of the wet channels is considered to be high, or when aging due to the effect of water or exposure to UV radiation is too pronounced. The cooling module may be replaced every 2 or 3 years, or every 5 years, for example. All or part of the removed cooling module may be recycled.

[0141] The device has a modular design, with each cooling module 3 able to be inserted into a base 4. The number of housings 5 formed in a base, and therefore the number of cooling modules it can accommodate, depends on the required cooling capacity. The modular design simplifies the manufacture of the device, as the same cooling module may be inserted into bases of different shapes, dedicated to different applications: domestic application, application in industrial buildings, or application in a means of transport.

[0142] Another notable advantage is that the base 4 and each cooling module 3 may be handled independently of each other. This limits the mass of the components to be handled, particularly during installation. Preferably, during installation, the base is fixed to a host structure, for example a civil engineering structure. The cooling modules are then inserted one after the other into the base.

[0143] Preferably, the base 4 is configured so that the ventilation system 6 can simultaneously address different cooling modules. Thus, the first fan and the second fan allow hot air to be admitted into several cooling modules and / or hot and humidified air to be extracted from said cooling modules.

Examples

Embodiment Construction

[0065]FIG. 2 shows a detail of a plate stack 2 of a device that is the subject of the invention. The device is intended to blow cooled air into a room.

[0066]A room denotes any enclosure in which the air is to be cooled. The room may be a room in a building, such as a residential or industrial building, or a room in a means of transport, such as a vehicle cabin.

[0067]The geometry of the stack is similar to that described in application WO2022184871. FIG. 2 shows four plates. The stack may comprise several dozen or even hundreds of plates, for example between 30 and 1000 plates 10. The plates 10 are arranged parallel to each other, perpendicular to a transverse axis Z. Each plate 10 extends parallel to a plane PXY. Each plate extends, parallel to a longitudinal axis X, according to a length l, and, parallel to a lateral axis Y, according to a width L. The stack extends, parallel to the transverse axis Z, according to a height h. The height h depends on the number of plates. The length...

Claims

1. An indirect evaporative cooling air conditioning device, the device being configured to blow cooled air into a room, the device comprising:an air intake for admitting air to be cooled; anda plurality of plates forming a stack, the plates being spaced apart from each other along a transverse axis, each plate of the plurality of plates comprising a dry face opposite a wet face, the wet face of each plate being configured to be wetted by water, each plate being configured to be cooled by the evaporation of water from the wet face;wherein, in the stack:two adjacent plates delimit a channel, the channel being:either a dry channel, delimited by two dry faces of two adjacent plates,or a wet channel, delimited by two wet faces of two adjacent plates;the plates are arranged so as to alternate dry channels and wet channels, each dry channel being adjacent to a wet channel;each dry channel extends along a longitudinal axis between a dry inlet, connected to the air intake, and a cold outlet, the cold outlet being configured to blow cooled air from the dry channel; andeach wet channel extends along the longitudinal axis between a wet inlet and a wet outlet the wet outlet being configured to evacuate humidified air following flow through the wet channel, the wet inlet being configured to receive part of the air emerging from the dry channel;and wherein:the stack is held in a cooling module; andthe cooling module is configured to be inserted into a base and removed from the base, the base defining a housing into which the cooling module may be inserted, the base being arranged to receive the air to be cooled, and / or to evacuate the humidified air resulting from the stack and / or to blow the cooled air.

2. The device according to claim 1, wherein:the base defines a housing, the housing being configured to be occupied by the cooling module; andthe housing is configured to allow the cooling module to be translated within the housing, so as to insert the cooling module into the housing or remove the cooling module from the housing.

3. The device according to claim 2, wherein the device comprises at least two cooling modules, and the base defines different housings, each housing being configured to receive a respective one of the cooling modules.

4. The device according to claim 1, wherein:the base extends between a front face and a rear face; andwhen the cooling module is inserted into the base, the front face and / or the rear face form a stop to define a position of the cooling module in the base.

5. The device according to claim 1, wherein each wet face of a set of wet faces of wet channels is coated with a capillary structure that promotes capillary water diffusion along the wet face.

6. The device according to claim 1, whereineach wet channel extends between a wet inlet and a plurality of wet outlets, distributed along the lateral axis;wet outlets of different wet channels are aligned parallel to the transverse axis; andthe stack comprises at least one closure wall, extending opposite the wet outlets aligned along the transverse axis, the closure wall delimiting an evacuation chamber, configured to collect the humidified air leaving each wet channel.

7. The device according to claim 1, wherein the base comprises or is configured to be connected to a ventilation system, arranged to allow air to be cooled to enter the dry channels and / or air resulting from the wet channels and / or cooled air resulting from the dry channels to be discharged.

8. The device according to claim 1, wherein the cooling module comprises at least one support wall, the support wall being configured to rest on a seal when the cooling module is inserted into the base, the seal being disposed between the support wall and the base.

9. The device according to claim 8, wherein:the base has a front face and a rear face; andthe cooling module has a front support wall and a rear support wall, so that when the cooling module is inserted into the base:the rear support wall bears against the rear face;the front support wall bears against the front face;a front seal is placed between the front support wall and the front face;a rear seal is placed between the rear support wall and the rear face;so as to ensure a seal between:(i) the cold outlets of the dry channels and an internal space, extending around the cooling module, between the front support wall and the rear support wall, and delimited by the base; and(ii) the wet outlets of the wet channels and the internal space.

10. The device according to claim 9, wherein the front support wall and the rear support wall form annular walls extending around the cooling module.

11. A method for cooling air in a room, using the device according to claim 1, comprising:operating the ventilation system so as to:admit air to be cooled through the air intake of the device;direct a portion of the cooled air, having flowed through a dry channel, into a wet channel;blow another portion of the cooled air, from the dry channel, into the room; andevacuate the humidified air flowing out of each wet channel to the outside of the room; andwetting the wet faces of different plates of at least one stack of the device.

12. The device according to claim 2, wherein:the base extends between a front face and a rear face; andwhen the cooling module is inserted into the base, the front face and / or the rear face form a stop to define a position of the cooling module in the base.

13. The device according to claim 3, wherein:the base extends between a front face and a rear face; andwhen the cooling module is inserted into the base, the front face and / or the rear face form a stop to define a position of the cooling module in the base.

14. The device according to claim 2, wherein each wet face of a set of wet faces of wet channels is coated with a capillary structure that promotes capillary water diffusion along the wet face.

15. The device according to claim 3, wherein each wet face of a set of wet faces of wet channels is coated with a capillary structure that promotes capillary water diffusion along the wet face.

16. The device according to claim 4, wherein each wet face of a set of wet faces of wet channels is coated with a capillary structure that promotes capillary water diffusion along the wet face.

17. The device according to claim 2, whereineach wet channel extends between a wet inlet and a plurality of wet outlets, distributed along the lateral axis;wet outlets of different wet channels are aligned parallel to the transverse axis; andthe stack comprises at least one closure wall, extending opposite the wet outlets aligned along the transverse axis, the closure wall delimiting an evacuation chamber, configured to collect the humidified air leaving each wet channel.

18. The device according to claim 3, whereineach wet channel extends between a wet inlet and a plurality of wet outlets, distributed along the lateral axis;wet outlets of different wet channels are aligned parallel to the transverse axis; andthe stack comprises at least one closure wall, extending opposite the wet outlets aligned along the transverse axis, the closure wall delimiting an evacuation chamber, configured to collect the humidified air leaving each wet channel.

19. The device according to claim 4, whereineach wet channel extends between a wet inlet and a plurality of wet outlets, distributed along the lateral axis;wet outlets of different wet channels are aligned parallel to the transverse axis; andthe stack comprises at least one closure wall, extending opposite the wet outlets aligned along the transverse axis, the closure wall delimiting an evacuation chamber, configured to collect the humidified air leaving each wet channel.

20. The device according to claim 5, whereineach wet channel extends between a wet inlet and a plurality of wet outlets, distributed along the lateral axis;wet outlets of different wet channels are aligned parallel to the transverse axis; andthe stack comprises at least one closure wall, extending opposite the wet outlets aligned along the transverse axis, the closure wall delimiting an evacuation chamber, configured to collect the humidified air leaving each wet channel.

Images