FR2658271A1 - Device for sucking in and discharging gases or fumes and installation comprising a plurality of such devices - Google Patents

Abstract

Device for sucking in and discharging gases or fumes comprising lower elements (5) and upper elements (6) associated by members (7), a passage (8) between the elements (5, 6) in a general Venturi shape, and a pipe (9) passing through the lower element (5) and opening in the passage (8), characterised in that it also comprises, in combination, means (22) of driving a gaseous fluid which promotes the sucking in and the discharge of the gases or fumes and comprises means (23) of feeding with gaseous fluid, means of circulating the gaseous fluid in the form of a channel (24) which are associated with the means of feeding (23) and end in means (25) of distribution directed towards the passage (8).

Description

DEVICE FOR SUCTION AND RELEASE OF GAS OR
PUNISHES AND INSTALLATION COMPRISING A PLURALITY OF SUCH
DEVICES
The invention relates to a device for the suction and rejection of gas or smoke and an installation comprising a plurality of such devices.

 Devices are already known for the suction and rejection of gases or fumes, intended to be mounted on buildings. Such devices are for example of the type comprising a lower element, an upper element, spacers for rigidly holding these two coaxial elements spaced from one another so as to define between them a passage, and a conduit passing through the element lower and opening into the passage.

 The lower and upper elements are limited by conical or frustoconical side walls, so that the passage has, in axial section, a general shape of venturi or convergent-divergent, along a radial direction orthogonal to the general axis of the device. This axis is generally at least substantially vertical. Such a device is generally mounted above the roof of the building for which it is intended. The conduit makes it possible to capture and channel the gases or fumes, which exit from this conduit at its upper end situated generally at the upper limit of the lower element, at the very place of the passage in the form of a venturi.

The gas or smoke flow is then diverted and entrained in this passage, thus formed, towards the outside of the device and the outside atmosphere. The presence of wind accelerates this process. Such a device is described, for example, in the document FR-A-1 403 955.

 According to documents FR-A-2 374 591 and FR-A-2 438 795 it is proposed to create an additional venturi effect comprising a deflector cap in a generally frustoconical shape, placed in the passage, facing and near the element inferior. This deflector cap is carried by gussets themselves fixed to the lower element. On its small base located towards the venturi-shaped passage, the deflector cap provides an opening in the form of a circular slot surrounding the duct at its upper downstream end for discharging gases or fumes in the passage. The aim and structure of such a structure is to improve the efficiency of the device in the event of light winds of horizontal direction or close to horizontal.

 According to document US-A-4 462 305, the device comprises static extraction means as defined above and mechanical extraction means active when the flow of gas or fumes discharged by the static means is less than a certain value limit. According to a first embodiment, the mechanical extraction means consist of a motorized centrifugal turbine placed in the venturi-shaped passage. According to a second embodiment, they are constituted by a helicoid placed in the duct. In either of these two embodiments, the mechanical means are completely integrated into the device, essentially housed in the duct or passage and act directly on the flow of gas or fumes circulating in the duct in order to speed it up.

 According to document FR-A-2 474 651, an installation for discharging into the ambient atmosphere of a gaseous fluid under pressure at high speed comprises a device as defined above and an evacuation machine connected to the conduit at its end. upstream. Such an installation is intended, for example, for a boiler, a painting installation. According to this document, the evacuation machine also acts directly on the flow of gaseous fluid to be discharged.

 The invention aims to propose a device of the general type described in document US-A-4,462,305 which is both at least, if not more, effective and at most, if not less, expensive.

 To this end and according to a first aspect, the invention provides a device for the suction and rejection of gases or fumes comprising a lower element, an upper element, members of association of the lower and upper elements spaced one of the other, a passage for gases or fumes between the lower and upper elements, in the general form of a venturi, and a conduit for gases or fumes passing through the lower element and opening into the venturi-shaped passage, characterized by the fact that it also comprises, in combination, means for driving a gaseous fluid promoting the suction and rejection of gases or fumes and comprising means for supplying gaseous fluid, means for circulating the gaseous fluid in the form of a pipe associated with the supply means and terminated by means for diffusing the gaseous fluid directed towards the passage, the supply means being placed outside the duct and of the venturi-shaped passage, the circulation means being separated from the duct and essentially placed outside the duct and of the venturi-shaped passage without substantially obstructing them.

 According to a second aspect, the invention provides an installation for the suction and rejection of gases or fumes which comprises a plurality of such devices, several devices having means for supplying common gaseous fluid. This gaseous fluid is, in particular, air.

It is therefore different from the gases or fumes released.

The invention will be described in more detail with reference to the accompanying drawings, in which
- Figures 1, 2, 3, 4 are four schematic views, in elevation and in vertical section of four possible variants of devices according to the invention.

 - Figure 5 is a schematic elevational view of an installation according to the invention.

 - Figures 6A to 6H are eight partial views of eight possible variants of opening in general form of the second, third and fourth alternative embodiments.

 The invention relates to a device 1 and an installation for the suction and rejection of gases or fumes. The installation comprises a plurality of separate devices 1 (for example in FIG. 5, two devices 1a, 1b).

 Such devices 1 are intended in particular for buildings 2 for residential or office or commercial or industrial use. They allow interior ventilation. To this end, such devices 1 are generally fixed to the roof 3 of the building 2 for which they are intended.

 We first describe an individual device 1, with reference to Figures 1 to 4 which illustrate four possible non-limiting variants.

 Whatever the variant, such a device 1 generally has an axis 4 which, when the device is mounted on the roof 3 of building 2 is most often vertical or close to vertical. By convention and for reasons of simplification and better understanding, the description is more particularly made in relation to this mounted position, which corresponds to that shown in Figures 1 to 5. The qualifiers of "upper", "lower", etc. ... must be understood in relation to this mounted position.

 The axis 4 is, preferably, an axis of revolution. It is in this variant that the following description is made. However in other embodiments, the axis 4 is only symmetrical or even only defines the general direction of the device 1.

 The device 1 comprises a lower element 5 an upper element 6; organs 7 for associating the lower 5 and upper 6 elements so that they are spaced coaxially and facing one another which provides between them a free passage 8 for gases or fumes in general form (in axial cross section) of venturi or convergent-divergent; and a conduit 9 for gases or fumes passing through the lower element 5 which is placed around and emerging through its downstream outlet opening 10 in the passage 8 (the qualifier "downstream" means with respect to the normal direction of gas circulation or smoke when rejected by the device 1).

 The conduit 9 has a certain axial length. It is intended to be connected to a duct (not shown) of the building 2 by means of flanges or the like.

 In a typical, but nonlimiting, form, the lower element 5 comprises an upper wall 11 of generally frustoconical shape, the small base 12 of which coincides with or in the immediate vicinity of the edge of the downstream outlet opening 10 and the large base of which 13 , constituting the outer edge of the lower element 5 is more axially spaced from the upper element 6 than is the small base 12. Preferably, the lower element 5 also has a lower wall having a large base or immediate proximity to the large base 13 and a small base 15 substantially symmetrical to the small base 12 relative to the plane of symmetry P separating the two walls 11, 14, defined by their large bases. The duct 9 projects axially from the bottom wall 14.

 In an equally typical form, the upper element 6 comprises a first lower wall 16 of generally conical shape (Figures 2 to 4) or frustoconical (Figure 1) and a second upper wall 17 of generally conical shape. The two walls 16, 17 have two large bases 18 common or close defining a plane of symmetry Q separating the two walls 16, 17. This or these large bases 18 define the outer edge of the upper element 6. Their vertices or small bases respective (19 for the bottom wall 16 and 20 for the top wall 17) are opposite one another and separated along the axis 4, the apex or small base 19 being turned towards and closest to the upper wall 11.

 The passage 8 is thus defined and limited by the upper 11 lower walls 16 opposite. The two elements 5, 6 thus defined preferably have substantially the same radial size, that is to say that the large bases 13, 18 come down, substantially from each other parallel to the axis 4. Also, preferably the angle a of opening of the walls 11, 14, 16, 17 is substantially the same, this angle a being between and degrees and more particularly between and degrees, in particular equal or close to degrees.

The walls 11, 14, 16, 17 can be made of solid metal sheet, the two constituent walls of the same element 5 or 6 being for example welded to each other by their large bases 13, 18 in particular thanks to an annular lip 21. In addition, in particular for some of the variant embodiments described below, the lower element 5 or upper 6 is essentially hollow, that is to say allows the passage of a gaseous fluid.

 The association members 7 are for example a plurality of spacers extending parallel to the axis 4, fixed to the lips 21. They can also be gusset plates arranged in one or more axial planes passing through the axis 4 .

 The spacing between the two elements 5, 6 is such that the vertices (real or virtual) of the walls 11 and 17 are coincident or close, in particular slightly spaced from one another.

 According to the invention, the device 1 also comprises, in combination, means 22 for driving a gaseous fluid promoting the suction and rejection of gases or fumes and comprising means 23 for supplying gaseous fluid, means for circulating the gaseous fluid in the form of a pipe 24 associated with the supply means 23 and terminated by means 25 for diffusing the gaseous fluid directed towards the passage 8, the supply means 23 being placed outside the duct 9 and of the passage 8 in the form of a venturi, the circulation means 24 being separated from the conduit 9 and essentially placed outside the conduit 9 and of the passage 8 in the form of a venturi without substantially obstructing them. The supply means 23 and circulation means 24 are separate and essentially external to the passage 8 and to the duct 9 and not confused with these.

The device makes it possible to use a gaseous fluid such as air different (as regards its nature, origin, characteristics) from the gases or fumes passing through the device 1.

 The supply means 23 may include, for example, a source of gaseous fluid such as compressed air (Figure 1, not shown) or a fan or other equivalent machine (Figures 2 and 5).

 The pipe 24 belonging to the means for circulation of the gaseous fluid is associated, in particular fixed, towards the diffusion means 25, directly or indirectly to the duct 9 (FIG. 1), and / or to the lower element 5 (FIG. 2), and / or to the upper element 6 (FIG. 3). In this section, the pipe 24 extends substantially perpendicular to the axis 4 (Figures 1 and 4) or in parallel (Figures 2 and 3).

 The supply means 23 can be separated from the elements 5 and 6 by a greater or lesser distance. Consequently, the pipe 24 can be more or less long and have a more or less tormented shape depending on the requirements imposed by the configuration of the building 2. In the general case, a single pipe 24 is provided per device 1.

However, a device 1 may possibly include several pipes 24.

 Referring now more particularly to FIG. 1 corresponding to a first alternative embodiment in which the diffusion means 25 comprise nozzle means placed at the end end portion 26 of the pipe 24 belonging to the means for circulating gaseous fluid and housed in the conduit 9 to the lower element 5. In this case the pipe 24 passes through the conduit 9 or the lower element 5 substantially radially, relative to the axis 4 of the device 1 and is connected to the nozzle means by an elbow 27. The nozzle means allowing a sliding of the gaseous fluid diverge in the direction of the upper element 6. The pipe 24 can be of small diameter it does not significantly obstruct the conduit 9 or the passage 8. It is, in the extreme part 26, of axis 4.

 Reference is now made more particularly to FIGS. 2, 3, 4 corresponding to a second, a third and a fourth variant in which the diffusion means 25 comprise an opening in the general form of a slot 28 closed on itself, placed around axis 4 of device 1 and passage 8 in the form of a venturi. The term “opening in the general form of a slot closed on itself” is understood here to mean any opening, whether single or not, extending in a generally continuous manner but possibly possibly having a certain discontinuity, along a line closed on itself ( in particular circular when the axis 4 is of revolution), the opening having a length along this line very substantially greater than the length orthogonally to this line. This therefore includes a single slot (FIG. 6A), a succession of slots placed one after the other along the line (FIG. 6B), a succession of holes placed one after the other along the line. (Figures 6D, 6G, 6H). This also includes the case where there are several radially spaced slots or holes (Figures 6C, 6F). This also includes the case of a combination of the previous cases (Figure 6E). The holes can be circular (Figures 6D, 6E) but also rectangular (Figure 6H) triangular (Figure 6G). All of these variants are not limiting, but only aim to explain how the opening in question can be organized.

 According to different possible embodiments, the slot-shaped opening 28 is adjacent to the duct 9 (FIG. 2), to the lower element 5 (FIG. 2), to the upper element 6 (FIG. 3). Or, again, the slot-shaped opening 28 is interposed between the duct 9 at or towards its downstream opening 10 and the lower element 5 at or towards its small base 12 adjacent to the passage 8 in the form of a venturi.

 The device 1 also includes an enclosure 29 of generally annular shape into which the pipe 24 belonging to the gaseous fluid circulation means opens out and in which the slot-shaped opening 28 is formed, this enclosure 29 allowing the circulation of the gaseous fluid . More particularly, the terminal end portion 26 is fixed to the enclosure 29 outside of the latter. To allow the circulation of the gaseous fluid, the enclosure 29 is essentially hollow.

Preferably in the enclosure are placed means 30 for distributing and distributing the gaseous fluid for a substantially equal flow of gaseous fluid along the slot-shaped opening 28. As a variant, this equal flow is obtained by distribution and distribution means 30 including an appropriate shape of the enclosure (in particular of variable size in cross section) and / or an appropriate shape of the openings 28.

As a variant, the distribution and distribution means 30 include baffles, grids, passages calibrated in order to ensure the pressure drops allowing said flow of gaseous fluid.

 In the case of the second variant of FIG. 2, the enclosure 29 is formed by and in the lower element 5.

 In the case of the third variant of FIG. 3, the enclosure 29 is formed by and in the upper element 6.

 In the case of the fourth variant of FIG. 4, the enclosure 29 is formed around the duct 9, outside of the latter, in particular adjoining or in the immediate vicinity of the lower element 5.

 Preferably, lips or equivalent are also provided, adjoining the slit-shaped opening 28 capable of orienting the flow of gaseous fluid properly. Referring now to Figures 2 and 4 which illustrate, more particularly the direction of the lips 31. In general, the lips 31 are directed between a first extreme position D1 substantially axial and a second extreme position D2 substantially coplanar with the lower element 5, upper 6 to which they are closest. More particularly, the lips 31 are directed at least substantially towards the outer edge 13, 18 of the lower element 5, upper 6 to which they are opposite. Thus, in the case of FIG. 2, the lips 31 are directed towards the edge diametrically opposite exterior of the lower element 5, upper 6 to which they are opposite, in a direction D4.

 In the case of the second variant (FIG. 2), the slot-shaped opening 28 formed between the duct 9 and the lower element 5, around, inside and in the immediate vicinity of the opening 10.

 In the case of the third variant (FIG. 3), the slot-shaped opening 28 is formed in the lower wall 16 of the upper element 6 opposite the lower element 5, between the axis 4 of the device and the outer edge 18 of said wall 16.

 In the case of the third variant (FIG. 4), the slot-shaped opening 28 is formed between the downstream end portion 32 of the duct 9, of tapered frustoconical shape and a parallel internal wall 39, also of frustoconical shape, s' extending over a greater axial length and connecting the small base 12 with the lower wall 14 which, in this variant, has a small base 15 with a larger radial dimension (and not equal) than that of the small base 12, being defined by l intersection of the wall 14 with a wall 34 in the form of a sleeve externally surrounding the duct 9, closed by a return 35 in the form of an annular disc perpendicular to the axis 4.

The enclosure 29 is in this case defined by the free space between the duct 9, the facing walls 33 and 34 and the return 35.

 According to a possible embodiment applicable to any of the variants, the device 1 further comprises means 36 for adjusting the flow rate of gaseous fluid in the means 22 for driving gaseous fluid.

These adjustment means 36 comprise for example a valve mounted on the pipe 24 belonging to the means for circulating gaseous fluid. In addition, the device 1 also comprises means 37 for controlling means 23 for supplying gaseous fluid and / or means 36 for adjusting the flow rate of gaseous fluid. Such control means 37 comprise, for example, a probe placed in the duct 9 in the vicinity of its downstream outlet opening 10 for measuring the pressure or the speed of the gases or fumes in the duct 9. The control means 37 thus ensure the control of the supply means 23 or / and of the adjustment means 36 via links 38.

 Reference is now made to FIG. 5 which illustrates an installation comprising a plurality of devices 1.

According to the invention, several (in particular the plurality) devices 1 have common supply means 23. For example, there is provided a single fan 23 having at its outlet a pipe 24 then dividing into two pipes 24a, 24b respectively for the two devices 1a, 1b. Where appropriate, the means for controlling the devices 1a, 1b may also be partly common. In such an installation, the fan 23 can be housed in the building 2 in particular in a protected lost area separated from the devices 1a, 1b.

 In the figures, the arrows V, G, A respectively indicate the flows of wind, gas or smoke, of the gaseous fluid used by the means 22.

 In the absence of operation of the means 22, the device 1 operates in the manner of a static device, it being specified that the means 22 do not at all or not substantially affect this operation. When necessary or desirable, in particular depending on the value of the significant parameter measured by the means 37, the means 22 are used. They improve the operation of the device 1 thanks to a flow of external gaseous fluid, distinct from the flow of gas or fumes, additional to it, suitably directed.

Claims (36)

 1. Device for the suction and rejection of gas or fumes comprising a lower element (5), an upper element (6), members (7) of association of the lower (5) and upper (6) elements spaced apart. 'one from the other, a passage (8) for gases or fumes between the lower and upper elements, generally in the form of a venturi, and a conduit (9) for gases or fumes passing through the lower element (5) and opening into the venturi-shaped passage (8), characterized in that it also comprises, in combination, means (22) for driving a gaseous fluid promoting the suction and rejection of gases or fumes and comprising means (23) for supplying gaseous fluid, means for circulating the gaseous fluid in the form of a pipe (24) associated with the supply means (23) and terminated by means (25) for diffusing the gaseous fluid directed towards the passage (8), the supply means (23) being placed outside the conduit (9) and the passage (8) in the form of a venturi, the circulation means (24) being separated from the conduit (9) and essentially placed outside the conduit (9) and the passage (8) in the form of venturi without substantially obstructing them.  2. Device according to claim 1, characterized in that the supply means (23) include a fan or a source of gaseous fluid such as compressed air.  3. Device according to claim 1, characterized in that the pipe (24) belonging to the means for circulation of the gaseous fluid is associated, in particular fixed, towards the means (25) of diffusion, with the conduit 9.  4. Device according to claim 1, characterized in that the pipe (24) belonging to the means for circulation of the gaseous fluid is associated, in particular fixed, towards the means (25) of diffusion, with the lower element (5).  5. Device according to claim 1, characterized in that the pipe (24) belonging to the means for circulation of the gaseous fluid is associated, in particular fixed, towards the means (25) of diffusion, with the upper element (6).  6. Device according to claim 1, characterized in that the diffusion means (25) comprise nozzle means placed at the end end portion (26) of the pipe (24) belonging to the means for circulation of gaseous fluid and housed in the conduit (9) to the lower element (5).  7. Device according to claim 6, characterized in that the pipe (24) belonging to the gaseous fluid circulation means passes through the duct (9) or the lower element (5) substantially radially, relative to the axis ( 4) of the device (1) and is connected to the nozzle means by an elbow (27).  8. Device according to any one of claims 6, 7, characterized in that the nozzle means allowing a sliding of the gaseous fluid diverge in the direction of the upper element (6).  9. Device according to claim 1, characterized in that the diffusion means (25) comprise an opening in the general form of a slot (28) closed on itself, placed around the axis (4) of the device (1 ) and the venturi-shaped passage (8).  10. Device according to claim 9, characterized in that the slot-shaped opening (28) is adjacent to the conduit (9).  11. Device according to claim 9, characterized in that the slot-shaped opening (28) is adjacent to the lower element (5).  12. Device according to claim 9, characterized in that the slot-shaped opening (28) is adjacent to the upper element (6).  13. Device according to any one of claims 1 and 9, characterized in that it comprises an enclosure (29) of generally annular shape into which opens the pipe (24) belonging to the gaseous fluid circulation means and in which is formed the slot-shaped opening (28), this enclosure (29) allowing the circulation of the gaseous fluid.  14. Device according to claim 13, characterized in that in the enclosure (29) are placed means (30) of distribution and distribution of the gaseous fluid for a substantially equal flow of gaseous fluid along the slot-shaped opening (28).  15. Device according to claim 14, characterized in that the means (30) of distribution and distribution comprise baffles, grids, passages calibrated in order to ensure the pressure drops allowing said flow of gaseous fluid.  16. Device according to claim 13, characterized in that the enclosure (29) is formed around the duct (9).  17. Device according to claim 16, characterized in that the enclosure (29) is placed outside the duct (9).  18. Device according to claim 16, characterized in that the enclosure (29) is adjacent to or in the immediate vicinity of the lower element (5).  19. Device according to claim 13, characterized in that the enclosure (29) is provided by and in the lower element (5).  20. Device according to claim 13, characterized in that the enclosure (29) is provided by and in the upper element (6).  21. Device according to claim 9, characterized in that it comprises lips (31) adjoining the slot-shaped opening (28) capable of properly orienting the flow of gaseous fluid.  22. Device according to claim 21, characterized in that the lips (31) are directed between a first end position (D1) substantially axial and a second end position (D2) substantially coplanar with the lower element (5), upper (6) to which they are closest.  23. Device according to claim 21, characterized in that the lips (31) are directed at least substantially towards the outer edge (13, 18) of the lower (5), upper (6) element to which they are opposite.  24. Device according to claim 23, characterized in that the lips (31) are directed towards the outer edge opposite the lower (5), upper (6) element to which they are opposite.  25. Device according to claim 23, characterized in that the lips (31) are directed towards the diametrically opposite outer edge of the lower (5), upper (6) element to which they are opposite.  26. Device according to any one of claims 10, 11, characterized in that the slot-shaped opening (28) is interposed between the duct (9) at or towards its downstream opening (10) and the element lower (5) to or towards its small base (12) adjacent to the venturi-shaped passage (8).  27. Device according to claim 12, characterized in that the slot-shaped opening (28) is formed in the lower wall (16) of the upper element (6) opposite the lower element (5) , between the axis (4) of the device and the outer edge (18) of said wall (16).  28. Device according to claim 9, characterized in that the pipe belonging to the means for circulation of the gaseous fluid extends substantially parallel to the axis of the device.  29. Device according to claim 9, characterized in that the pipe belonging to the means for circulation of the gaseous fluid extends substantially perpendicular to the axis of the device.  30. Device according to claim 1, characterized in that it further comprises means (36) for adjusting the flow rate of gaseous fluid in the means (22) for driving gaseous fluid.  31. Device according to claim 30, characterized in that the means (36) for adjusting the gaseous fluid flow rate comprise a valve mounted on the pipe (24) belonging to the gaseous fluid circulation means.  32. Device according to any one of claims 1, 30, characterized in that it further comprises means (37) for controlling means (23) for supplying gaseous fluid and / or means ( 36) for adjusting the flow rate of gaseous fluid.  33. Device according to claim 32, characterized in that the said control means (37) comprise a probe placed in the duct (9) in the vicinity of its downstream outlet opening (10) for measuring the pressure or the speed of the gases or fumes in the duct (9).  34. Device according to claim 1, characterized in that the lower element (5) comprises a wall of generally frustoconical shape (11) and the upper element (6) comprises a first lower wall (16) of generally conical shape or frustoconical opposite the lower element (6) and a second upper wall (17) opposite of generally conical shape.  35. Installation for the suction and rejection of gases or fumes, characterized in that it comprises a plurality of separate devices according to any one of claims 1 to 34, several devices having means for supplying gaseous fluid common.  36. Installation according to claim 35, characterized in that the gaseous fluid is air.