FR2916261A1 - AIR DIFFUSION SYSTEM IN AN ENCLOSURE - Google Patents

Abstract

An air diffusion system in an enclosure, said system comprising: a zone (11), called primary zone, having an inlet opening (12) for an air flow, called a primary air flow; , said secondary, having an inlet opening (14) of an air flow, said secondary, from said enclosure; and a zone (15), called tertiary zone, in which said primary (11) and secondary (13) zones open, said system further comprising means for mixing said primary and secondary flows providing a so-called tertiary air flow, diffused in said enclosure through an opening (16), said diffusion, said tertiary zone (14), said system being in the form of a one-piece assembly.

Description

-1- Air diffusion system in an enclosure

  The present invention relates to an air diffusion system in an enclosure.

  The field of the invention is the field of air diffusion in an enclosure or a cabin and the regulation of this diffusion. The invention applies more particularly to the diffusion of air in enclosures, such as hospital rooms, requiring on the one hand a good air circulation for reasons of hygiene and on the other hand a regulation fine quality of the air in the enclosure and the temperature inside the enclosure. There are currently many air distribution systems in an enclosure. These systems most often require the implementation of air flows while associating, according to the systems, a distribution of air, hot and cold water, static radiators or fan coils and insufflation grids. and extracting air. Among the existing systems, the SPILOTAIR system is known in particular. The latter comprises a heat treatment of the air using cylindrical terminal batteries and the suction of the ambient air of the enclosure by venturi effect. The venturi device and the terminal batteries are directly integrated in the ducts of the ventilation network or air distribution in the enclosure. The SPILOTAIR system has a first air diffusion grille in the room and a second grille to suck the ambient air.

  The major disadvantage of such a system is the complexity of setting up the various components of this system. Indeed, the establishment of the venturi device and the terminal batteries in the ducts is a delicate operation and requires a significant installation time. In addition, this type of system has separate grids for the diffusion of air into the room and the suction of the ambient air of the enclosure, which requires the establishment of at least two grids per chamber and connecting at least two grids to the air distribution network. These features imply, on the one hand many parts making the system expensive and an important system installation time making its installation somewhat practical. Moreover, the complexity of such a system makes maintenance difficult and expensive. An object of the invention is to overcome the aforementioned drawbacks. Another object of the invention is to provide an air diffusion system in an enclosure less complex than current systems. Finally, it is also an object of the invention to provide an air diffusion system in an inexpensive enclosure, easy to install and maintain. The invention thus proposes an air diffusion system comprising: a so-called primary zone having an inlet opening for an air flow, referred to as primary flow; a so-called secondary zone having an inlet opening for a so-called secondary air flow coming from said enclosure; and a so-called tertiary zone into which said primary and secondary zones open. This system further comprises means for mixing the primary and secondary flows providing a so-called tertiary air flow, diffused into the chamber through an opening, called diffusion, of the tertiary zone. The system according to the invention is in the form of a one-piece assembly. This one-piece assembly may comprise fastening means provided for fixing it to the level of the ceiling or a wall of the enclosure or on a surface located in the enclosure. The monoblock assembly may also be in the form of a rack or drawer to slide into a location that is secured to a wall or ceiling. The system according to the invention is easier to install than state-of-the-art systems and allows a great saving in installation time. In addition, the installation of the system according to the invention does not require any specific knowledge, and therefore no intervention on the part of a qualified person. It can be performed by an unqualified person. Moreover, the maintenance of the system according to the invention is also easier to achieve than the maintenance of the systems of the state of the art. Indeed, the one-piece assembly can be removed, cleaned and easily replaced. The monoblock system is also convenient to move, for example in the workshop, to carry out a particular maintenance if necessary. The primary flow may be a flow which has previously undergone any treatment by a treatment device and brought to or near the enclosure by means of a duct or ductwork network in which it is under pressure or no. More particularly, the primary air stream may be a stream of air, withdrawn from outside or provided by another device, and heat-treated by a heat treatment device, such as a heat pump device. The primary flow may be at a temperature for example between 8 and 35 C, which offers a wider range than in systems usually employed that use temperatures of the order of 14 to 32. Another advantage of the invention is the implementation of reduced air flow rates and the reduction of the dimensions of ducts and air handling units. Advantageously, the inlet opening of the secondary flow is close to the diffusion opening, so that the diffusion of the tertiary flow into the enclosure creates an induction effect favoring the admission of the secondary flow. in the secondary zone. Thus, the admission of the secondary flow into the secondary zone is facilitated by the diffusion of the tertiary flow. In addition, the proximity of the inlet opening of the secondary flow and the diffusion opening of the tertiary flow makes it possible to produce a one-piece assembly of reduced dimensions and thus of little space and to use a single grid for the secondary flow admission opening and diffusion opening of the tertiary flow into the room. In an advantageous version of the system according to the invention, the mixing means comprise a wall between the primary zone and the tertiary zone, effecting a mixture of the primary and secondary flux by the venturi effect under the action of the speed of the primary flow. Advantageously, the wall comprises a portion having a hollow shape traversed by the primary flow to pass from the primary zone to the tertiary zone, the section of the hollow shape gradually decreasing between an upstream end located on the side of the primary zone and a 2916261 - 4 downstream end located on the side of the tertiary zone so that the passage of the primary flow by the hollow form creates a venturi effect in the tertiary zone at the downstream end of the hollow form. In the remainder of the description we will designate this hollow form primary passage opening. This passage opening may for example be a nozzle, a funnel, of conical or rectangular shape to create a venturi effect when traversed by a flow at a medium speed or significant. In a simplified version, the wall may be substantially planar and have openings of passages or holes through the wall and through which the primary flow passes from the primary zone to the tertiary zone. In addition, the secondary flow passes from the secondary zone to the tertiary zone through a passage opening located near the downstream end of the hollow form, so that the venturi effect, generated by the speed of passage of the primary flow through the primary passage opening, created a depression favoring the passage of secondary flow from the secondary zone to the tertiary zone. In the remainder of the description, we will designate this passage opening opening of secondary passage. The primary flow and the secondary flow pass, respectively from the primary zone and the secondary zone, to the tertiary zone through the primary and secondary passage openings. The primary passage opening is in the wall separating the primary zone and the tertiary zone. Advantageously, this wall also separates the primary zone 25 and the secondary zone. The passage of the primary flow through the primary passage opening creates a depression at the downstream end of this opening. This depression is the result of the venturi effect obtained by the passage, at high speed, of the primary flow through the primary passage opening whose section gradually decreases in the direction of passage 30 of this primary flow. The depression created at the downstream end of the primary passage opening causes the passage of the secondary flow to the tertiary zone through the secondary passage opening which is close to the downstream end of the passage opening primary. In a particular embodiment, the passage opening from the secondary flow to the tertiary zone may be formed by an inclined wall extending substantially parallel to one of the side walls of the primary passage opening. . In an advantageous version, the system according to the invention may comprise means for admitting the primary flow into the primary zone. These intake means may comprise: suction means provided for sucking the primary flow to the mixing means. The suction means may comprise at least one fan arranged at the intake opening of the primary flow and making it possible to increase or decrease the admission speed of the primary flow; and / or primary flow admission flow control means, when the primary flow arriving at the primary flow inlet opening is under pressure or at a medium or high speed, such as in a network. primary flow distribution under pressure. These regulating means may comprise a piston equipped with a single flap 20, a butterfly flap, a flap, an iris, a diaphragm whose position is regulated to vary the admitted primary flow rate in the primary zone. These regulating means may be of the male or female type. The admission means, the primary flow in the primary zone and therefore to the mixing means, make it possible to vary directly or indirectly: the admission speed of the primary flow in the primary zone; the speed of the primary flow arriving towards the mixing means; The speed of passage of the primary flow through the primary passage opening; the venturi effect created by the passage of the primary flow through the primary passage opening; The admission speed of the secondary flow in the secondary zone; the proportions of secondary and primary flux during mixing, and therefore the composition of the tertiary flux; and the diffusion of tertiary flux into the enclosure. Thus, the admission means make it possible to vary the composition of the tertiary flux diffused in the chamber by varying the proportions of the primary and secondary flux that are mixed. Moreover, the admission means vary the admission flow rate of the secondary flow and the flow rate of the tertiary flow diffused into the enclosure. Thus, it is possible to create either a depression or an overpressure in the enclosure. When the chamber is a hospital chamber, the system according to the invention makes it possible: to create and maintain an overpressure in the chamber in order to achieve a confinement of a patient with respect to the outside in the case for example of immunodeficient diseases; or to create and maintain a depression in the chamber to achieve external confinement with respect to a patient, for example in the case of highly contagious pathologies. The admission means make it possible to make the system according to the invention independent of the pressure of the distribution network of the primary flow. The system according to the invention may furthermore comprise a fourth zone having an intake opening of a fourth stream coming from the enclosure, and an opening for the passage of this fourth stream from the fourth zone to the tertiary zone for mix with the primary and secondary streams. In this case the tertiary flow is composed of the primary and secondary flows, and the fourth flow. The system according to the invention may comprise ventilation means arranged at the passage opening of the fourth flow promoting the passage of the fourth flow from the fourth zone to the tertiary zone. Thus, the user has an additional control means of the composition and the temperature of the tertiary flow. It can vary the composition and temperature of the tertiary stream by adding the fourth stream to the primary and secondary streams. In addition, by varying the operation of the ventilation means arranged at the passage opening of the fourth flow, the user has the possibility of varying the proportion of the fourth flow mixing with the primary and secondary flow and therefore of to regulate finely the composition and the temperature of the tertiary flux diffused in the enclosure. Advantageously, the inlet opening of the fourth flow in the fourth zone may be close to the diffusion opening of the tertiary flow in the enclosure, so that the diffusion of the tertiary flow into the enclosure creates an effect induction promoting the admission of the fourth flow in the fourth zone. In a particular embodiment, the fourth zone may be part of the secondary zone. In this case, the fourth flow is the secondary flow, the inlet opening of the fourth flow is the inlet opening of the secondary flow. The system according to the invention may furthermore comprise means for treating the primary flow, more particularly heat treatment means, arranged between the intake opening of the primary flow and the mixing means, and intended to be traversed by the primary flow. Thus, the system according to the invention makes it possible to regulate the temperature of the primary flow and therefore indirectly of the tertiary flux diffused in the enclosure to either heat or cool the enclosure. The primary flow may not be heat treated, in which case the system according to the invention makes it possible to ventilate the enclosure or to replace the air in the enclosure. The arrangement of the different zones in the monobloc assembly makes it possible to have a compact assembly, of reduced size and easy to handle. In a particular arrangement, the mixing means separates the one-piece assembly into two parts, one comprising the primary zone and the other comprising the secondary zone and the tertiary zone. The secondary and tertiary zones are superimposed and separated by at least one wall. In the case where the system according to the invention has a fourth zone, as described above, the fourth zone may be below the tertiary zone, more particularly at the same level as the secondary zone. The fourth zone may, for example, be arranged in the assembly so as to separate the secondary zone into two parts. Such an arrangement of the zones makes it possible to have a single grid for the 5 openings: of diffusion of the tertiary flux into the enclosure, of admission of the secondary flow into the secondary zone, and of admission of the fourth flow into the fourth zoned. The one-piece assembly may be provided with fixing means 10 for fixing it to a surface in the enclosure, for example in a false ceiling. These fastening means can be snap-type, or rack or drawer for convenient installation and uninstallation of the system. According to another aspect of the invention there is provided an air diffusion installation comprising at least one air diffusion system according to the invention. Such an installation may comprise a heat pump supplying a heat-treated primary stream to a plurality of air diffusion systems each located in an enclosure, by means of a network of primary flow distribution ducts. The temperature of the primary flow 20 supplied to the air diffusion systems may be constant, each of the systems then making it possible to independently regulate the temperature of the tertiary flux diffused in the enclosure by means of heat treatment means of the system according to the invention. The regulation of the air diffusion temperature in each chamber can be achieved by means of an electronic control module. This electronic control module can also make it possible to control and regulate the flow rate of the different flows in order to produce a vacuum or an overpressure in the enclosure as described above. Each control and regulation module can be connected to a central supervision module. This central supervision module can acquire the operating data of each of the broadcasting systems through communication with the control and regulation modules associated with each of the systems. It can also remotely modify the operation of each of the broadcasting systems, individually, by acting on the associated control modules. Other advantages and features will become apparent upon consideration of the detailed description of a non-limiting embodiment, and the accompanying drawings in which FIG. 1 is an isometric view of a first version. of the system according to the invention without regard to the housing in which it is in operation; FIG. 2 is a representation in a plan view of the system of FIG. 1; FIG. 3 is a representation of the system of FIG. 1 viewed from the side of the intake opening of the primary flow; Figure 4 is a representation of the system of Figure 1 in a view of the side of the diffusion opening of the tertiary flow; Figure 5 is a representation of the system of Figure 1 in a side view; Figure 6 is a representation of the system of Figure 1 in a sectional view; Figure 7 is a representation of a second version of the system according to the invention without regard to the housing in which it is in operation; Figure 8 is a top view of the system of Figure 1 with the housing in which it is in operation; Figure 9 is a representation of the system of Figure 8 according to a side view of the inlet opening of the primary flow; FIG. 10 is a representation of the system of FIG. 8 in a view of the side of the diffusion opening of the tertiary flow; and FIG. 11 is a representation of the system of FIG. 8 in sectional view

  Figure 1 is an isometric view of a first version of the system according to the invention. In Figure 1, as well as in Figures 2 to 6, the outer casing of the system has been omitted voluntarily for clarity. Of course, in operation the system is in a housing as shown in Figures 8 to 11. We will now give a description of this first version of the system according to the invention with reference to Figures 1 to 5 which give a representation according to different views of the system shown in Figure 1 and Figure 6 which is a representation of the system of Figure 1 in a sectional view with respect to the axis AA shown in Figure 2. The system comprises a primary zone 11 having an inlet opening 12 of a primary flow, two secondary zones 13 each having an inlet opening 14 of a secondary flow coming from the enclosure, a tertiary zone 15 having a diffusion opening 16 10 of a tertiary flow in the chamber and a fourth zone 17 having an inlet opening 18 of a fourth flow also coming from the enclosure. The system further comprises means 19 for admitting the primary flow to heat treatment means 20 of this primary flow. The primary flow is admitted by the intake means 19, comprising a piston head 191 mounted on a piston 192. The primary flow admitted into the primary zone is directed towards the heat treatment means 20, for example heating means with electric battery or water or air conditioning means for heating or cooling the primary flow if necessary. Thus, the primary stream may be heat treated by the heat treating means 20 as it passes therethrough. As needed, the primary stream can either be heated or cooled. The primary flow then passes through a wall 21, separating the primary zone from the tertiary zone. This wall comprises a passage opening 22 of the primary flow from the primary zone 11 to the tertiary zone 15. The passage opening 22 is a hollow shape, in the wall 21, through which the primary flow from its upstream end 22a located on the side of the primary zone 11 towards its downstream end 22b located on the tertiary zone 15 side. The section of the passage opening 22 decreases in the direction of circulation of the primary flow, that is to say of the primary zone 11 towards the tertiary zone 15 or from its upstream end 22a to its downstream end 22b ,. The passage of the primary flow through the passage opening 22, at medium or high speed, creates a venturi effect near the downstream end 22b of the passage opening 22. This passage opening 22 may for example be a nozzle , an opening of a conical or funnel-shaped shape or of any other form making it possible to create a venturi effect at the level of the tertiary zone 15 under the effect of the speed of passage of the primary flow. On the side of its downstream end 22b, the passage opening 22 comprises several through holes 23 allowing the passage of the primary flow in the tertiary zone 15. The secondary flow is admitted to the secondary zones 13 through the inlet openings 14. This secondary flow passes secondary zones 13 to the tertiary zone 15 through a passage opening 24 located near the downstream end 22a of the passage opening 22. Thus, the effect 10 venturi created at the level of the downstream end 22b of the passage opening 22 through the passage of the primary flow promotes the passage of the secondary flow from the secondary zones 13 to the tertiary zone 15. The passage opening 24 is formed by a wall 25 which extends from the zones secondary to the proximity of the downstream end 22b of the passage opening 22, substantially parallel to one of the side walls of the passage opening 22. This wall can be profiled so as to obtain the maximum effect. As described above, the system according to the invention further comprises a fourth zone 17 having an inlet opening 18 of a fourth flow from the workpiece. This fourth zone 17 further comprises a passage opening 26 of the fourth flow to the tertiary zone 15. The system further comprises suction means 17, for example a fan, arranged at the passage opening 26 and favoring the passage of the fourth flow from the fourth zone to the tertiary zone 15. The admission means 19 allow the user to vary directly or indirectly: the admission speed of the primary flow in the primary zone 11; The speed of the primary flow arriving towards the passage opening 22; the speed of passage of the primary flow through the passage opening 22; - the venturi effect created by the passage of the primary flow through the passage opening 22; the rate of admission of the secondary flow in the secondary zone 13; 5 - the diffusion of the tertiary flow in the enclosure. Thus, the admission means 19 for varying the composition of the tertiary flow by varying the proportions of the primary and secondary flow that mixes at the level of the tertiary zone. They also make it possible to create either a depression or an overpressure in the enclosure. When the chamber is a hospital chamber, the system according to the invention makes it possible: to create and maintain an overpressure in the chamber to achieve confinement of a patient with respect to the outside in the case, for example, of immunodeficient pathologies ; or to create and maintain a depression in the chamber to achieve external confinement with respect to a patient, in the case for example of highly contagious pathologies. Thus, thanks to the admission means 19, the user has a means for controlling the pressure in the chamber. Furthermore, by varying the operation of the ventilation means 27 arranged at the passage opening 26 of the fourth flow, the user has the possibility of varying the proportion of the fourth flow mixing with the primary and secondary flow and therefore to regulate more finely the composition of the tertiary flux diffused in the enclosure. In addition, the heat treatment means 20 make it possible to regulate the temperature of the primary flow and therefore of the tertiary flux diffused in the enclosure, for: either heating the enclosure; to cool the enclosure. The primary flow may not be heat treated in which case the system according to the invention allows for ventilation of the enclosure or simply a renewal of the air of the enclosure. Advantageously, the inlet opening 14 of the secondary flow in the secondary zone 13 is close to the diffusion opening 16 of the tertiary flow in the enclosure. The inlet opening 18 of the fourth flow is between the inlet openings 14 of the secondary flow. The diffusion opening 16 of the tertiary flow is located above the inlet openings 14 and 18 over the entire width of the system. This arrangement allows for a system of reduced dimensions and therefore compact. The primary stream may have undergone any pretreatment by a treatment device before being brought into proximity or into the enclosure by means of a conduit or duct network. This pretreatment may be a heat treatment carried out by a heat pump. The temperature of the primary flow arriving at the inlet opening 12 of the system can be constant, at a temperature ranging between 8 and 35 C. The paths of the different flows are shown schematically by solid arrows in FIGS. 5 and 6.

  Figure 7 shows a second version of the system according to the invention in a profile view. In the version shown in Figure 7, the wall 25 forming the passage opening of the secondary flow of the secondary zone 13 to the tertiary zone 15 is more rounded and the passage opening 22 is less elongated. In addition, the passage opening 26 has a position closer to the wall 25. In addition, the fourth zone is part of the secondary zone. Figures 8 to 10 are each a representation of the system of Figure 1 in its housing in different views. Figure 11 is a representation of the system of Figure 1 in its housing in a sectional view with respect to the axis BB shown in Figure 8. The housing 28 has a non-polluting thermal and acoustic envelope and approved by the standards of protection fire. The housing includes holes 28 for easily snap into a base attached to a surface of the enclosure. The system further comprises a front grille 30 disposed in front of the inlet openings 14 of the secondary flow, the inlet opening 18 of the fourth flow and in front of the diffusion opening 16 of the tertiary flow. The system according to the invention implements a double internal induction: one at the level of the passage opening 24 and the other at the level of the passage opening 26. Thus, it makes it possible to treat 1 to 3 volumes of air coming from the enclosure (secondary flow and fourth flow) for 1 volume of primary air (primary flow). In addition, by using a low temperature primary stream, for example around 8 C, and at medium or high speed, it allows, on the one hand, a large induction, and on the other hand, to reduce the dimensions ducts of the distribution network of the primary flow. This results in energy savings of 10 to 15% compared to existing air distribution systems. As described above, the system according to the invention makes it possible to manage: the ventilation of an enclosure, the temperature of the enclosure, and the pressure of the enclosure. The invention is very hygienic because it has no dead zone where germs or condensates could develop. Moreover, the system described above can be implemented in an air diffusion installation. Such an installation may comprise a heat pump providing a heat-treated primary stream to a plurality of air diffusion systems each located in an enclosure, by means of a network of primary flow distribution ducts. The temperature of the primary flow supplied to the air diffusion systems can be constant, each of the systems then making it possible to independently regulate the temperature of the tertiary flux diffused in the enclosure. The regulation of the air diffusion temperature in each chamber can be achieved by means of an electronic control module. This electronic control module can also make it possible to control and regulate the flow rate of the different flows in order to produce a vacuum or an overpressure in the enclosure as described above. Each control and regulation module can be connected to a central supervision module. This central supervision module can acquire the operating data of each of the broadcasting systems through communication with the control and supervision modules associated with each of them. It can also remotely modify the operation of each of the broadcasting systems, individually, by acting on the associated control modules. The parameterization of each of the systems can be done by any means such as for example by computer or telecommunication means, such as for example a Pocket PC, connected by Bluetooth connection to each control and regulation module. The central supervision module can be connected to a touch screen. The supervision can be done over a TCP / IP connection, thus making it possible to use an existing network in the enclosure.

Of course, the invention is not limited to the examples detailed above.

Claims (15)

  1. System for diffusing air into an enclosure, said system comprising: a zone (11), said primary, having an inlet opening (12) of a flow of air, said primary; a zone (13), said secondary, having an inlet opening (14) of a secondary air flow from said enclosure; and - a zone (15), called tertiary zone, into which said primary (11) and secondary (13) zones open, said system further comprising means for mixing said primary and secondary flows supplying a so-called tertiary air flow, diffused in said enclosure through an opening (16), said diffusion of said tertiary zone (15), said system being in the form of a one-piece assembly.   2. System according to claim 1, characterized in that the inlet opening (14) of the secondary flow is close to the diffusion opening (16) of the tertiary flow, so that the diffusion of the tertiary flow in The enclosure creates an induction effect favoring the admission of the secondary flow into the secondary zone (13).   3. System according to any one of claims 1 or 2, characterized in that the mixing means comprises a wall (21) between the primary zone (11) and the tertiary zone (15), through which the primary flow and performing a mixture of primary and secondary flow by venturi effect under the action of the flow rate of the primary flow.   4. System according to claim 3, characterized in that the wall comprises a portion having a hollow shape (22), said primary passage opening, through which the primary flow passes from the primary zone (11) to the tertiary zone (15), the section of said hollow form (22) decreasing progressively between an upstream end (22a) located on the side of the primary zone (11) and a downstream end (22b) located on the side of the tertiary zone. (15) so that the passage of said primary stream by said hollow form (22) creates a venturi effect in the tertiary zone (15) at said downstream end (22b).   5. System according to claim 4, characterized in that the secondary flow passes from the secondary zone (13) to the tertiary zone (15) through a passage opening (24), called secondary, located near the end downstream (22b) of the hollow form (22), so that the created venturi effect favors the passage of the secondary flow from the secondary zone (13) to the tertiary zone (15).   6. System according to claim 5, characterized in that the secondary passage opening (24) is formed by a wall (25) extending substantially parallel to one of the side walls of the hollow form (22).   7. System according to any one of the preceding claims, characterized in that it comprises a fourth zone (17) having an inlet opening (18) of a fourth flow from the enclosure.   8. System according to claim 7, characterized in that it comprises a passage opening (26) of the fourth flow of the fourth zone (17) to the tertiary zone (15) to mix with the primary and secondary flow, the flow tertiary then being composed of the primary and secondary flows and the fourth flow.   9. System according to claim 8, characterized in that it comprises ventilation means (27) arranged at the passage opening (26) of the fourth flow promoting the passage of the fourth flow of the fourth zone (17). to the tertiary zone (15).   10. System according to any one of claims 7 to 9, characterized in that the inlet opening (18) of the fourth flow is close to the diffusion opening (16) of the tertiary flow, so as to the ee 2916261 - 18 - diffusion of the tertiary flux in the enclosure creates an induction effect favoring the admission of the fourth flow in the fourth zone (17).   11. System according to any one of the preceding claims, characterized in that it comprises intake means (19) provided for sucking the primary flow to the mixing means.   12. System according to claim 11, characterized in that the admission means (19) comprise at least one suction means and / or one regulating means arranged at the inlet opening (FIG. 12) of the primary stream.   13. System according to any one of the preceding claims, characterized in that it further comprises heat treatment means (20) of the primary flow arranged between the inlet opening (12) of the primary flow and the means of mixing, and intended to be traversed by the primary flow.   14. An air diffusion installation comprising at least one air diffusion system according to any one of the preceding claims.   15. Installation according to claim 14, characterized in that the primary flow is previously treated by a heat pump device.