FR3139621A1 - Air conditioning system using indirect evaporative cooling - Google Patents

Abstract

An air conditioning device with indirect evaporative cooling, the device being intended to blow cooled air into a room, the device comprising: an air intake, intended to admit air to be cooled; a plurality of plates, forming a stack, each plate comprising a dry side opposite a wet side, the wet side of each plate being configured to be kept wet by water, each plate being intended to be cooled under the effect from an evaporation of water, from the wet side; the device being such that: two adjacent plates are spaced from one another, along a transverse axis, so as to form 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.

Description

Air conditioning device by indirect evaporative cooling

The technical field of the invention is an air cooling device by indirect evaporative cooling.

PRIOR ART

Indirect evaporative cooling air coolers, also referred to as indirect adiabatic dew point coolers, have been known for several decades.

The principle of such coolers is schematized on the . It is based on the use of an evapo-exchanger, within which the incoming air (arrow F ₁ in solid line on the ), is cooled, without humidification, potentially to its dew point. Cooling is produced by air circulation in contact with a plate P ₁ , called a cooling plate, cooled by evaporation of water. The cooling plate has a dry side, in contact with which the air to be cooled flows, and a wet side, wetted by water, the water being symbolized by circles on the surface. . On the , the mixed dashed arrows represent cooled or cooling air.

Part of the cooled air, in contact with the dry side of the cooling plate, is evacuated, so as to cool a part: arrow F ₂ . Another part of the cooled air is reinjected into the cooler and directed so as to flow in contact with the wet face of the cooling plate: arrow F ₃ . The air thus reinjected heats up, evaporating the water present on the wet side of the cooling plate. This results in a drop in the temperature of the cooling plate. The air thus heated, loaded with humidity, is then evacuated outside the room.

Compared to the most common air conditioning devices, a notable advantage of such coolers is the absence of refrigerant. These devices must only be powered by water. This results in a more favorable environmental impact than usual air conditioners, based on the compression of a refrigerant. We know that refrigerants can have harmful consequences on the environment.

An example of an indirect cooling device has been described in WO2016134417. In this device, the air to be cooled flows in channels parallel to each other. The same is true for air circulating through channels with wet faces. But the arrangement of coplanar channels, separated from each other, is not optimal in terms of pressure loss.

An example of an indirect evaporative cooling device has been described in application PCT/EP2022/055490. The invention described below is an improvement of this device, to optimize the air flow in the device and the compactness.

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

• an air intake, intended to admit air to be cooled;
• a plurality of plates, forming a stack, the plates being spaced from each other along a transverse axis, each plate having a dry side opposite a wet side, the wet side of each plate being configured to be wetted by water , each plate being intended to be cooled under the effect of evaporation of water, from the wet side, each plate extending along a longitudinal axis, between a first border and a second border, each border forming a end of the plate in a plane perpendicular to the transverse axis;

the device being such that, in each stack:

• two adjacent plates delimit a channel, the channel being:
  • either a dry channel, delimited by two dry faces of two adjacent plates,
  • either a wet channel, delimited by two wet faces of two adjacent plates;
• 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, two adjacent dry and wet channels respectively being connected by a fluid junction;
• each dry channel extends, along the longitudinal axis, between an air inlet, connected to the air intake, and a cold outlet, the cold outlet being intended for an evacuation of cooled air following the air flow in the dry channel;
• each wet channel extends along the longitudinal axis, between the fluid junction and a wet outlet, the wet outlet being intended for an evacuation of humidified air following the flow in the wet channel;

the device can be such that

• the wet outlets of each wet channel are distributed along a lateral axis, perpendicular to the longitudinal axis and the transverse axis;
• the stack comprises several wet pipes, distributed along the lateral axis, each wet pipe being connected to several wet outlets of different respective wet channels of the stack, each wet pipe being configured to receive humidified air emerging from different wet channels ;
• the wet pipes from the stack open into the same wet collection chamber;
• the wet collection chamber opens onto an evacuation opening, configured to evacuate the humid air collected in the wet collection chamber, the wet collection chamber extending between the wet pipes of the stack and the opening of evacuation.

According to one possibility, the device comprises several wet collection chambers, each wet collection chamber being connected to one or more stacks (30), the respective evacuation openings of the wet collection chambers opening into the same secondary collection chamber (40 ), so that the air emerging from each of said wet collection chambers is collected in the secondary collection chamber.

The device may comprise two adjacent stacks, each stack comprising several wet pipes, distributed along the lateral axis, each wet pipe being connected to several wet outlets of different respective wet channels of the stack, each wet pipe being configured to receive humidified air emerging from different humid channels. The wet collection chamber can extend between the two adjacent stacks.

According to one possibility,

• the device comprises two adjacent stacks along the transverse axis;
• the wet pipes from said two adjacent stacks open into the wet collection chamber.

According to one possibility:

• the device comprises two adjacent stacks, along the longitudinal axis, the adjacent stacks being arranged on either side of a central cavity;
• the two adjacent stacks are each connected to a wet collection chamber;
• the respective evacuation openings of each of the wet collection chambers open into the central cavity, the central cavity forming the secondary collection chamber.

According to one possibility, each stack comprises:

• a front part, comprising the air inlets of the dry channels and the wet outlets of the wet channels of the stack, as well as the wet pipes;
• a rear part, comprising the cold outlets of the dry channels of the stack.

The wet collection chamber may be configured to direct air from the front portion to the rear portion of the stack, with the exhaust opening emerging from the rear portion of the stack.

According to one possibility, each stack comprises

• a front part, comprising the air inlets of the dry channels and the wet outlets of the wet channels of the stack, as well as the wet pipes;
• a rear part, comprising the cold outlets of the dry channels of the stack;
• a longitudinal face, connecting the front part and the rear part.

The wet collection chamber may be configured to direct air from the front portion toward the longitudinal face of the stack, with the exhaust opening extending across the longitudinal face of the stack.

According to one possibility, the device comprises a cold collection chamber, connected to the respective cold outlets of dry channels of the stack, the cold collection chamber being configured to collect the air emerging from each cold outlet.

According to one possibility:

• the stack is connected to at least several intake pipes, distributed along the lateral axis, each intake pipe being connected to several dry inlets of different respective dry channels of the stack, each intake pipe being configured to distribute the air to be cooled in different dry channels;
• the intake pipes extend from the same intake chamber, the intake chamber forming the air inlet to be cooled.

According to one possibility:

• each wet pipe extends, perpendicular to the transverse axis, in a cross section;
• the or each wet collection chamber extends, perpendicular to the transverse axis, in a cross section;
• the cross section of the or each wet collection chamber is greater than the cross section of each wet pipe to which the or each wet collection chamber is connected.

FIGURES

There describes the principles of adiabatic cooling.

There shows an example of stacking of plates, forming dry channels and wet channels.

Figures 3A to 3J show a first embodiment of the invention

Figures 4A to 4C show a second embodiment of the invention.

PRESENTATION OF SPECIAL MODES OF REALIZATION

There shows a detail of a stack 30 of plates of a device which is the subject of the invention. The device is intended to blow cooled air into a room.

The geometry of the stack is similar to that described in application PCT/EP2022/0055490. The stack can include a few 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 , and, parallel to a lateral axis Y, along a width . The stack extends, parallel to the transverse axis Z, at a height . The height depends on the number of plates.

Apart from the first and last plates, delimiting the device along a transverse axis Z, each plate 10 has a wet face 10 _w and a dry face 10 _d . The respectively dry and wet faces of the same plate are opposite, in the sense that they are spaced apart by the thickness of the plate. The thickness of each plate, along the Z axis, is as small as possible, taking into account mechanical strength constraints. The thickness depends on the material forming the plate. The thickness can be between 10 µm and 1 mm, or even between 10 µm and 500 µm. The invention exploits the conduction of heat along the Z axis, through each plate 10.

A 10 _w wet face is intended to be wetted with water as regularly as possible. The water can be placed directly on the plate, or indirectly, the plate comprising, at the wet side, a material, called wet material, soaked in water. It may for example be a material allowing water to be pumped by capillary action, from a water supply. The material may for example include cellulose or a polymer structure. Wetting of a wet face can also be ensured by fluidic channels, provided along the wet face, and allowing pumping of water by capillary action, from the water supply. In the remainder of the description, the term plaque includes a possible capillary structure formed or deposited on the plaque.

The stacking is such that the wet (respectively dry) sides of two consecutive plates face each other. Two wet faces 10 _w , facing each other, and belonging to two adjacent plates, delimit a wet channel 20 _w . Two dry faces 10 _d , facing each other, and belonging to two adjacent plates, delimit a dry channel 20 _d . The channels, dry or wet, are delimited by two lateral uprights, not shown, extending along a plane XZ. The side uprights are spaced from each other by the width of each plate, along the lateral axis Y.

Thus, the stack is formed by an alternation between dry channels 20 _d and wet channels 20 _w . Each dry channel extends, along the longitudinal axis X, between an air inlet 20 _d,in and a cold outlet 20 _d,out . The ventilation system is configured to allow air flows through dry channels and wet channels. The cold outlet 20 _{d, out} can be intended to be connected to a cooled air exhaust, configured to blow the cooled air inside the room.

The air to be cooled is sucked into the device by a ventilation system, not shown on the , through an admission. The ventilation system includes one or more fans. In the example of the , the air to be cooled is admitted parallel to a longitudinal axis X.

Each dry channel 20 _d is connected to an adjacent wet channel 20 _w by a fluid junction 21. Each wet channel 20 _w extends, along the longitudinal axis X, between the fluid junction 21 and a wet outlet 20 _{w, out} . The fluid junction 21 is arranged between the air inlet 20 _d,in and the cold outlet 20 _d,out , or at the level of the cold outlet 20 _d,out . The fluid junction 21 is advantageously closer to the cold outlet 20 _d,out than to the air inlet 20 _d,in . Thus, considering the direction of air flow in the dry channel, the fluid junction 21 is arranged in the dry channel 20 _d , upstream of the cold outlet 20 _{d, out} or at the level of 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 20 _d is admitted into a wet channel 20 _w adjacent to it through the fluid junction 21. The fluid junction 21 can be formed by a simple opening made in the plate separating the wet channel from the dry channel. In the examples shown, the fluid junction 21 is formed at a second edge, forming a longitudinal end of the plate. Part of the cooled air is then sucked into at least one wet channel 20 _w adjacent to the dry channel 20 _d , at the level of the cold outlet 20 _{d, out} . The air flow flowing into the wet channel 20 _w is adjusted by the device's ventilation system. This is facilitated by the fact that the flow, in each dry channel, is preferably carried out according to a laminar regime, the air speed being for example between 0.5 ms ^-1 and 3 ms ^-1 .

The fluid junction 21, coupled to the ventilation system, can be such that 50 to 75% of the air flow flows towards the cold outlet 20 _{d, out} , while 25% to 50% of the air flow flows flows through the fluidic junction, towards the wet channel 20 _w . Note that the flow of air through each wet channel 20 _w is carried out in a direction opposite to the flow of air in the dry channel adjacent to it. The device is thus configured to operate against the current.

The length can be between 5 cm and 1m, and preferably between 10 cm and 30 cm. The length is preferably:

• less than the width , for example at least 1.5 times less, or even at least 2 times less or at least 3 times less than the width .
• and/or less than the height , for example at least 1.5 times lower, or even at least 2 times lower or at least 3 times lower than the height .

Two adjacent plates 10 are spaced from one another, 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 can advantageously be between 0.5 mm and 2 mm.

In the example shown, each plate is flat. According to possible variants, the edges of two adjacent plates can move closer or further away from each other. Bringing two adjacent plates together and moving them apart makes it possible to form openings and partitions respectively. An example of plate reconciliation is described in connection with the .

Each plate 10 comprises lights 11, extending around an axis parallel to the transverse axis Z. The first lights 11 are preferably arranged near the same longitudinal edge of each plate. By longitudinal edge (or end), we mean one of the edges of the plate 10 along the longitudinal axis _{longitudinal axis} In the example shown in Figures 2A to 2E, each light 11 forms a wet outlet 20 _{w, out} of a wet channel 20 _w .

Two first lights 11 respectively formed on two adjacent plates 10 delimiting the same wet channel 20 _w open into the latter. Thus, a wet channel 20 _w is in fluidic communication with at least one first light 11. Two first lights 11, respectively formed on two adjacent plates, delimiting the same dry channel 20 _d , and aligned along the evacuation axis, are connected to each other by a waterproof wall 15, crossing the dry channel and forming a wet pipe. The waterproof wall is tubular, around the evacuation axis. The stack is arranged so that different waterproof walls are aligned around an axis parallel to the transverse axis. Each alignment forms a wet pipe 17.

Each tubular watertight wall 15 crossing a dry channel 20 _d can be obtained by a watertight seal, or by a local rapprochement of the walls delimiting the dry channel, as shown in the figure. .

Figures 3A to 3J show a first embodiment of a device according to the invention. On the , we have shown a part of a stack 30 of plates 10. The is a 3D representation from a couple plane parallel to the transverse axis Z and the lateral axis Y. The plates 10 of the stack 30 alternately delimit dry channels 20 _d and wet channels 20 _w . The dry channels 20 _d comprise sealed walls 15. Each sealed wall 15 crossing a dry channel is obtained by locally bringing together the two plates delimiting said channel. In this example, the plates delimiting each dry channel are placed in contact with one another, which forms the sealed wall 15.

There is an enlarged view of the stack shown on the . There are three wet pipes 17, distributed along the lateral axis Y. Each wet pipe is connected to several wet outlets of different respective wet channels of the stack. Each wet pipe receives humidified air emerging from different wet channels

There shows two adjacent stacks 30 _i , 30 _s identical to the stack 30 shown in Figures 3A and 3B. The stacks 30 _i , 30 _s extend along the transverse axis Z. A wet collection chamber 35 extends between the stacks 30 _i , 30 s. The humid collection chamber 35 is intended to receive the humid air flowing through different humid pipes 17 of at least one stack. In the example shown on the , the wet collection chamber 35 has inlet openings 37 and an evacuation opening 39. Each inlet opening 37 is connected to a wet pipe 17. Thus, the inlet openings are distributed along the lateral axis Y. Each wet pipe 17 opens onto an inlet opening 37.

In this embodiment, each stack comprises several wet pipes 17, distributed along the lateral axis Y. Each wet pipe 17 is connected to several wet outlets of different respective wet channels of the stack. Each wet pipe is configured to receive humidified air emerging from different wet channels. The wet collection chamber 35 extends between the two adjacent stacks. Thus, the wet pipes 17 of the two adjacent stacks open into the wet collection chamber. The wet collection chamber 35 opens onto the evacuation opening 39. The latter is configured to evacuate the humid air collected in the wet collection chamber 35. Thus, the wet collection chamber 35 extends between the pipes wet from the stack 17 and the evacuation opening 39.

Each wet pipe 17 extends, in a plane perpendicular to the transverse axis Z, in a cross section. Likewise, the wet collection chamber 35 extends, in a plane perpendicular to the transverse axis Z, in a cross section. The cross section of the wet collection chamber 35 is greater than the cross section of each wet pipe 17. Preferably, the cross section of the wet collection chamber 35 is equal, or at least equal to the accumulation of the cross sections of each pipe humidity to which it is connected. This limits the pressure loss.

In the example shown on the , the wet collection chamber is delimited, along the transverse axis Z, by a lower wall 35 _i and an upper wall 35 _s . The wet collection chamber has inlet openings 37 provided on the lower wall 35 _i and on the upper wall 35 _s . The inlet openings provided on the lower wall collect the humidified air coming from the humid pipes 17 of the lower stack 30 _i . The inlet openings provided on the upper wall collect the humidified air coming from the humid pipes 17 of the upper stack 30 _s . On the , the upper face 35 _s of the wet collection chamber 35 is shown.

As shown on the , each stack 30 extends between a front face 30f and a rear face 30r. The front and back faces are opposite each other. The front and rear faces extend parallel to the longitudinal axis Y and the transverse axis Z. The front and rear faces are connected by two lateral faces 30l. Each side face 30l extends along the transverse axis Z and the longitudinal axis X. The inlet of each dry channel and the outlet of each wet channel open onto the front face. The wet pipes 17 extend along the front face. The wet collection chamber extends from the front side to the rear side. The evacuation opening 39 opens from the rear face. On the , we have shown, on each stack, only the plates extending at the ends of the stack. It is the same for Figures 3F to 3J.

The cooled air emerges from each dry channel, at the rear face 30 _r of each stack.

There shows different stacks 30 _a , 30 _i , 30 _s forming a first part 1A of a device 1. As described in connection with the , the stacks 30 _i , 30 _s are adjacent stacks along the transverse axis Z. A first wet collection chamber 35 ₁ is arranged between the two stacks 30 _i and 30 _s . A second wet collection chamber 35 ₂ is arranged between the two stacks 30 _i and 30 _a . In the example shown, the stack 30 _i is segmented into two halves. The humid air emerging from a first half of the humid channels, closest to the first humid collection chamber 35 ₁ , propagates towards the latter. ^. The humid air from a second half of the channels, closest to the second humid collection chamber 35 ₂ , propagates towards the latter. On the , the flow of humid air, through the stacks, was shown by straight arrows

It is understood that within the stack 30 _i , the direction of the flow of the humid air emerging from each wet channel depends on the relative position of the wet channel relative to the collection chambers coupled to the stack. Such a configuration makes it possible to reduce the pressure loss resulting from the flow of humid air through the wet pipes. In fact, the distance between each outlet of a wet channel and the wet collection chamber is less than or equal to half the height h of the stack. If the humidified air emerging from all the wet channels flowed to the same wet collection chamber, the distance between each outlet of a wet channel and the wet collection chamber could be between h/2 and h for the channels the most distant. This would lead to an increase in pressure loss, which would result in greater energy consumption of the device's ventilation system. In the configuration shown on the , the maximum distance traveled by the humid air, between an outlet of a humid channel and the humid collection chamber, is less than or equal to h/2.

On the , a secondary collection chamber 40 is also shown. The secondary collection chamber 40 is connected to several wet collection chambers. On the , the secondary collection chamber 40 is connected to the first wet collection chamber 35 ₁ and to the second wet collection chamber 35 ₂ . The secondary collection chamber 40 has different inlet openings 41, each inlet opening being configured to be connected to an evacuation opening 39 of a wet collection chamber 35. The secondary collection chamber 40 has an opening of evacuation 42. The evacuation opening 42 allows evacuation of the air having flowed through the secondary collection chamber 40.

Thus, each stack 30 is coupled to at least one wet collection chamber 35. And different wet collection chambers 35 are associated with the same secondary collection chamber. This arrangement allows a certain homogenization (within ± 10% or ± 20%) of the air flow in each wet column, and consequently, in each wet channel. This is due to the fact that the pressure loss seen by the humid air propagating in each wet channel is relatively homogeneous in the different wet channels.

On the , an inlet 51 of an evacuation chamber 5 described below is shown. Inlet 51 is connected to evacuation opening 42.

There shows the device 1, comprising the first part 1A, described in connection with Figures 3F and 3G, as well as a second part 1B. The stacks 30 forming the first part 1A are adjacent, along the longitudinal axis X, the stacks 30 forming the second part 1B. The device comprises a central cavity 2, extending between the stacks forming parts 1A and 1B respectively. Parts 1A and 1B are symmetrical with respect to a plane parallel to the lateral axis Y and to the transverse axis Z, and passing into the central cavity 2, equidistant from parts 1A and 1B. Within the same part, each stack 30 is connected to at least one wet collection chamber 35. The secondary collection chamber 40 extends into the central cavity 2. The secondary collection chamber 40 is configured to collect the humid air resulting from the humid collection chambers 35. The arrangement of the secondary collection chamber in the central cavity, between stacks forming the first and second parts 1A, 1B, allows a gain in compactness.

The cooled air emerges from each stack into the central cavity 2. The central cavity 2, around the secondary collection chamber 40, forms a cold collection chamber, connected to the respective cold outlets of dry channels of each stack. The cold collection chamber is configured to collect air emerging from each cold outlet.

There shows the first part 1A of the device previously described, connected to an evacuation chamber 5. The evacuation chamber 5 extends between an interface 51, connected to the secondary collection chamber 40, and an evacuation conduit 52. The evacuation chamber includes a fan 50, ensuring the flow of humid air successively through the wet pipes 17, the wet collection chambers 35, the secondary collection chamber 40 and the evacuation chamber 5.

There shows the device described in connection with Figures 3F to 3H. An intake chamber 3 is shown, allowing the admission of air to be cooled towards the inlet of the dry channels 20 _d , as well as an outlet collector 6, configured to direct the cooled air collected into the central cavity 2 towards the room to be cooled. The outlet collector includes a fan 60, so as to blow the cooled air into a room to be cooled.

Figures 4A to 4C represent a device 1' according to a second embodiment. The device comprises stacks extending between a front face 1f and a rear face 1r. There represents the exterior of the device 1'. There represents a sectional view in a plane passing through the transverse axis Z and the lateral axis Y. The general structure of the device according to the second embodiment is similar to that of the device according to the first embodiment. The device is divided into two symmetrical parts 1A, 1B. Each part comprises stacks aligned along the transverse axis and separated from each other by a wet collection chamber 35. Each stack comprises a succession of dry channels and wet channels. The cutting plane passes through the wet pipes 17 which collect the humid air emerging from each wet channel. Each stack 30 is arranged between two collection chambers 35.

As described in connection with the first embodiment, inside each stack, the humid air flows in two opposite directions towards the nearest humid collection chamber 35. On the , the flow of humid air is shown by straight arrows. This makes it possible to limit the pressure loss, as described in connection with the .

At the outlet of each wet pipe 17, the humid air propagates inside a collection chamber 35, up to an evacuation opening 39. Unlike the previous embodiment, the wet collection chamber 35 is configured to direct the air from the towards the longitudinal face 30 _l of the stack. Each evacuation opening 39 extends over the longitudinal face 30 _l of a stack.

The device comprises a first part 1A and a second part 1B. The respective stacks of each part 30 are aligned along the longitudinal axis Z. A central cavity 2 extends between the two parts 1A, 1B. Two adjacent stacks, along the lateral axis Y, belonging respectively to two different parts, are separated by the central cavity. The central cavity serves as a secondary collection chamber 40. The latter is connected to the wet collection chambers 35 of each stack. The secondary collection chamber opens into an evacuation chamber 5, taking the form of a conduit. The circulation of humid air successively in the humid pipes 17, the humid collection chambers 35 and the secondary collection chamber 40, is controlled by a fan 50.

On the , each stack includes a solid middle plate 32, closing the wet pipes 17. In each pipe, the propagation of the humid air resulting from the wet channels is carried out from the middle plate 32 towards the inlet openings 37. The middle plate 32 also provides a mechanical holding function for each stack. It is inserted into notches made in the 30 _l side face of the stacks.

On the , we have shown the rear face 1 _r and the front face 1 _f of the device 1'. The front face allows the admission of air to be cooled, through an admission chamber 3. The admission chamber forms the inlet of air to be cooled. The rear face allows a flow of cooled air, opening dry channels.

The second embodiment is particularly suitable for a configuration in which the rear face of the device is placed against a wall. This makes it possible to obtain a device whose bulk, along the longitudinal axis X, is reduced.

According to a variant, the device can be such that at least one stack is connected to at least several intake pipes, distributed along the lateral axis Y. Each intake pipe is connected to several inlets of different respective dry channels of stacking. Each intake line is configured to distribute the air to be cooled into different dry channels. According to such a variant, the intake pipes connected to the stack extend from the same intake chamber, the intake chamber forming the air inlet to be cooled.

The invention allows optimized management of air flows, in particular humid air, by limiting pressure losses. It thus allows a certain homogenization of the air flow circulating in the stack channels. It also makes it possible to offer compact devices, or whose geometry is adapted to a particular use.

Claims (11)

Air conditioning device (1) with indirect evaporative cooling, the device being intended to blow cooled air into a room, the device comprising:

• an air intake, intended to admit air to be cooled;
• a plurality of plates (10), forming a stack (30), the plates being spaced from each other along a transverse axis (Z), each plate comprising a dry face (10 _d ) opposite a wet face (10 _w ) , the wet face of each plate being configured to be wetted by water, each plate being intended to be cooled under the effect of water evaporation, from the wet face, each plate extending along a longitudinal axis, between a first border and a second border, each border forming one end of the plate in a plane perpendicular to the transverse axis;

the device being such that, in each stack:

• two adjacent plates delimit a channel, the channel being:
  • either a dry channel (20 _d ), delimited by two dry faces (10 _d ) of two adjacent plates,
  • either a wet channel (20 _w ), delimited by two wet faces (10 _w ) of two adjacent plates;
• 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, two adjacent dry and wet channels respectively being connected by a fluid junction (21);
• each dry channel (20 _d ) extends, along the longitudinal axis (X), between an air inlet (20 _{d, in} ), connected to the air intake, and a cold outlet (20 _{d, out} ), the cold outlet being intended for an evacuation of cooled air following the flow of air in the dry channel;
• each wet channel (20 _w ) extends along the longitudinal axis, between the fluid junction (21) and a wet outlet (20 _{w, out} ), the wet outlet being intended for an evacuation of humidified air following the flow in wet channel;

the device being characterized in that:

• the wet outlets of each wet channel are distributed along a lateral axis (Y), perpendicular to the longitudinal axis and the transverse axis;
• the stack comprises several wet pipes (17), distributed along the lateral axis, each wet pipe being connected to several wet outlets of different respective wet channels of the stack, each wet pipe being configured to receive the humidified air emerging from different wet channels;
• the wet pipes of the stack open into the same wet collection chamber (35);
• the wet collection chamber opens onto an evacuation opening (39), configured to evacuate the humid air collected in the wet collection chamber, the wet collection chamber extending between the wet pipes (17) of the stack and the evacuation opening.

Device according to claim 1, comprising several wet collection chambers (35), each wet collection chamber being connected to one or more stacks (30), the respective evacuation openings of the wet collection chambers opening into the same collection chamber secondary (40), so that the air emerging from each of said wet collection chambers is collected in the secondary collection chamber. Device according to claim 2 in which device comprises two adjacent stacks, each stack comprising several wet pipes, distributed along the lateral axis, each wet pipe being connected to several wet outlets of different respective wet channels of the stack, each pipe humid being configured to receive humidified air emerging from different humid channels. Device according to claim 3, in which the wet collection chamber extends between the two adjacent stacks. Device according to claim 4, in which:

• the device comprises two adjacent stacks along the transverse axis;
• the wet pipes from said two adjacent stacks open into the wet collection chamber.

Device according to any one of claims 2 to 5, in which:

• the device comprises two adjacent stacks, along the longitudinal axis, the adjacent stacks being arranged on either side of a central cavity (2);
• the two adjacent stacks are each connected to a wet collection chamber;
• the respective evacuation openings of each of the wet collection chambers open into the central cavity, the central cavity forming the secondary collection chamber.

Device according to any one of the preceding claims, in which each stack comprises:

• a front part, comprising the air inlets of the dry channels and the wet outlets of the wet channels of the stack, as well as the wet pipes;
• a rear part, comprising the cold outlets of the dry channels of the stack;

and in which the wet collection chamber is configured to direct air from the front part to the rear part of the stack, the exhaust opening opening from the rear part of the stack. Device according to any one of the preceding claims, in which each stack comprises

• a front part, comprising the air inlets of the dry channels and the wet outlets of the wet channels of the stack, as well as the wet pipes;
• a rear part, comprising the cold outlets of the dry channels of the stack;
• a longitudinal face, connecting the front part and the rear part;

and wherein the wet collection chamber is configured to direct air from the front portion toward the longitudinal face of the stack, the exhaust opening extending across the longitudinal face of the stack. Device according to any one of the preceding claims, comprising a cold collection chamber, connected to the respective cold outlets of dry channels of the stack, the cold collection chamber being configured to collect the air emerging from each cold outlet. Device according to any one of the preceding claims, in which:

• the stack is connected to at least several intake pipes, distributed along the lateral axis, each intake pipe being connected to several dry inlets of different respective dry channels of the stack, each intake pipe being configured to distribute the air to be cooled in different dry channels;
• the intake pipes extend from the same intake chamber, the intake chamber forming the air inlet to be cooled.

Device according to any one of the preceding claims, in which:

• each wet pipe extends, perpendicular to the transverse axis, in a cross section;
• the or each wet collection chamber extends, perpendicular to the transverse axis, in a cross section;
• the cross section of the or each wet collection chamber is greater than the cross section of each wet pipe to which the or each collection chamber is connected.