WO2010107378A1

WO2010107378A1 - An air supply device

Info

Publication number: WO2010107378A1
Application number: PCT/SE2010/050296
Authority: WO
Inventors: Bengt Sellö; Martin SELLÖ
Original assignee: Inventiair Ab
Priority date: 2009-03-20
Filing date: 2010-03-17
Publication date: 2010-09-23
Also published as: EP2409089A4; SE0900359A1; EP2409089A1; EP2409089B1; SE534160C2

Abstract

An air supply device for blowing air into a room is disclosed. The device has a casing (2) with two opposite, first and second side walls (21, 22) and a third wall there between, provided with a supply air opening (4). In the interior of the casing, there is an air feed tube (3) provided with feed openings (31-34) arranged so as to bring inlet air towards two pocket portions (25) located on each side of the supply air opening (4). The inlet air will circulate in a tornado-like air flow in the pocket portions and interact with the air from the room before it flows out through the supply air opening (4) into the room. Hereby the room climate will be improved.

Description

AN AIR SUPPLY DEVICE

Field of the invention

The present invention relates to an air supply device for blowing air into a room, possibly provided with a heat exchanger for the supply of warm or cold air. The device is of the kind being intended to be arranged adjacent to a wall, in the floor or some other structural part of a room, e.g. adja- cent to a pillar.

More specifically, the air supply device is of the kind comprising an air feed tube, a box-like casing accommodating said feed tube, and feed openings in said feed tube for feed- ing supply air via the interior of the casing, via a supply air opening in a casing, and thereupon into said room.

Background of the invention

Devices of the kind indicated above are previously known, and are used frequently in public and private buildings. They can also be used in vehicles and vessels, such as air craft and ships .

In order to increase the comfort for persons staying in the room, it is also known to dispose such air supply devices near the floor or at least in such a way that the air blown into the room enters in the lower part of the room so as to replace the existing air which may be too hot or too cold and which may also contain impurities. The fresh air will then displace the used air and will normally flow upwards towards the ceiling where outlet openings are arranged for drawing off air. In this way, the climate in the lower part of the room can be maintained in a comfortable state. A drawback with existing apparatus is that the air being blown into the room is often too cold or too hot, since it often has to be many degrees warmer or colder than the aver- age room temperature in the lower part of the room. Moreover, if the air velocity is too high, this will also be uncomfortable to persons staying in the room.

Object of the invention

Against this background, a main object of the present invention is to provide an air supply device, which will give a well controlled air flow into the room, without too high air velocity but still maintaining a steady air flow, whereby the climate in the room is kept comfortable. A further object, in case the air blown into the room is heated or cooled, is to reduce the difference in temperature between the air fed into the device and the average room temperature.

Summary of the invention

According to the present invention, these objects are achieved in that the casing of the device has two opposite, first and second side walls and a third wall therebetween where the supply air opening is located, and two opposite, parallel, longitudinally extending pocket portions formed inside the casing on each side of the supply air opening, adjacent to the first and second side walls, respectively, and in that the feed openings in the feed tube are located and configured so as to bring the inlet air to flow into the pocket portions and cause a tornado-like air flow in each pocket portion, whereby the air circulating in the tornado- like air flow interacts with air from the room before it flows out through the supply air opening into the room. Because of the tornado-like air flow, there will be a drop in static pressure adjacent to such circulating air, which will draw ambient air into interior of the casing. Thus, even though there is a net flow of air outwardly through the supply air opening, there will be some air flow in the opposite direction, from the room adjacent to the device into the interior of the casing of the device. In this way, the inlet air will be mixed somewhat with the air in the room before it is blown out through the air supply opening. Accordingly, there will be some interaction and a certain equalization of the inlet air and the air in the room. Consequently, persons staying close to the air supply device will not feel the difference as much as was the case with prior art devices of this kind. This is especially true if the inlet air is much colder than the room temperature.

According to a further aspect of the invention, the feed openings in the feed tube may comprise at least two rows of air nozzles or openings, each row extending longitudinally along the casing and the nozzles or openings being directed obliquely toward the first or the second side wall. Preferably, such rows of air nozzles or openings are configured to cause an air curtain striking at an oblique angle against the first or the second side wall, whereupon the air is deflected and transformed into the above-mentioned tornado-like air flow in the associated pocket portion. With such an arrangement, a stable air flow can be maintained even for a relatively low air flow. There may be two, three or even more rows of nozzles or openings on each side, forming associated air curtains striking at slightly different angles onto the inside of the first and second side walls of the casing, respectively. Because of the relatively high air velocity in the respective air curtain and the adjoining tornado-like air flow, there will be an additional suction effect drawing air from the room through the supply air opening into the interior of the casing.

Most preferably, the rows of air nozzles or openings should be situated so as to direct the air curtains obliquely towards the respective pocket portion on each side of the sup- ply air opening.

The pocket portions may be defined by straight wall portions at right angles to each other, e.g. defined by a part of the first or the second side wall, a part of the third wall, and flange walls extending along the supply air opening inwardly from the third wall into the interior of the casing. As an alternative, each pocket portion may be defined, at least partly, by a semi-cylindrical or curved wall portion merging with the first or the second side wall of the casing.

In order to heat or cool the inlet air, heat exchangers may be arranged in one or both of the pocket portions, e.g. in the form of longitudinally extending pipes for leading through a hot or a cold fluid. This will give a particularly efficient thermal exchange, since the inlet air is circulating in the pocket and will thereby interact effectively with the hot or cold pipes. Of course the pipes may be provided with flanges or the like to make the heat exchange even more effective.

Of course, the box-like casing may be secured to a wall of the room, either horizontally, or standing on the floor, but preferably close to a wall. It is also possible to mount the air supply device adjacent to some other structural part of the room or at the floor, either flush with the floor or slightly underneath. In the latter case, it is advantageous to provide an extended chamber adjacent to the supply air opening and to mount an upper grid flush with the floor for passing through the inlet air into the room.

These and other features are set forth in the dependent claims and will also be apparent from the detailed description below, with reference to the appended drawings.

Brief description of the drawings

Figure 1 illustrates schematically, in a perspective view, an air supply device according to the present invention, an end wall of a casing being left out to make the interior of the casing visible;

Figure 2 shows, likewise in a perspective view, an air feed tube, in a larger scale;

Figure 3 shows a cross-section through the casing of the air supply device shown in figure 1;

Figure 4 shows a modified embodiment of the air supply device according to the invention;

Figure 5 illustrates schematically how the air supply device according to the invention can be mounted at a wall of a room;

Figure 6 shows an alternative mounting of the air supply device on the floor adjacent to a wall of the room; and Figure 7 illustrates the mounting of the device in the floor of a room.

Detailed description of preferred embodiments

The air supply device 1 shown in figures 1, 2 and 3 comprises a box-like, elongated casing 2, a feed tube 3 extending inside and along the casing 2 and a supply air opening 4 in a wall of the casing. The elongated casing 2 has, in this em- bodiment, a rectangular cross-section (figure 3) with upper and lower, first and second walls 21 and 22 and a third wall 23, extending between the opposite walls 21, 22 and being provided with the above-mentioned supply air opening 4. The latter extends in the longitudinal direction of the casing along a large part of the third wall 23, as is clearly seen in figure 1. The longitudinal extension of the supply air opening 4 may be shorter or longer than the one shown in figure 1.

The feed tube 3 is connected to an air inlet conduit or some other source (not shown) for fresh inlet air. In the illustrated embodiment, it extends along the full length of the casing 2. The air feed tube 3 is cylindrical with a circular cross-section (figure 3) in this embodiment, but the cross- sectional shape is not critical. At the left end of the casing, as shown in figure 1, an end wall (not shown) will close the casing 2, and the feed pipe 3 should either be provided with a closing end wall or be connected to an extended inlet air conduit.

As is clearly shown in figure 2, the air feed tube 3 is provided with four rows of small feed openings or nozzles 31, 32 and 33, 34, these rows being parallel to each other and ex- tending along the length of the tube 3, at least along a length corresponding to the supply air opening 4.

These feed openings 31-34 are constituted by relatively small circular holes, preferably with a diameter not exceeding 5 mm, in particular about 4 mm and not being smaller than 3 mm. Instead of drilled bores, these openings may be formed by punched holes having a collar, or they may alternatively be made by a separate insert portion being formed so as to pro- duce a well-defined air stream. In any case, the air streams from the row of holes 31-34 will form an air curtain directed radially outwardly from each row of holes.

According to the invention, the feed openings in the form of rows of holes 31-34 should be arranged in such a way as to direct the air curtains Cl, C2 and C3, C4 (see fig. 3) obliquely against the first and second side walls 21 and 22, respectively, in a direction towards the third wall 23.

In this way, the air curtains C1-C4 will strike at an oblique angle against the first and second side walls 21, 22 of the casing, and then they will be deflected and transformed into a tornado-like air flow in an adjacent region of the casing, to the right in figure 3.

For this purpose, the casing portions on each side of the inlet opening 4 are formed as a pocket-like configuration serving to lead the flowing air into an elongated, circulating air flow having a tornado-like configuration. This is illustrated schematically in figure 3 by arrows T.

In the embodiment shown in figures 1-3, the pocket-like portions 25 of the casing are constituted by a portion of the first and second side wall 21, 22, respectively (to the right in figure 3) , an upper or lower part of the third wall 23, and a flange wall extending along the supply air opening 4 inwardly from the third wall 23 into the interior of the casing 2. These flange walls are denoted 24. Accordingly, the supply air opening is configured like a rectangular box with open sides (see also figure 1) .

In order to maintain a steady flow of air inside the casing 2, the curtains Cl, C2, C3, C4 or jet streams (possibly being distributed in the longitudinal direction) must have a certain velocity, typically in the interval 8-14 m/s. Also, the oblique direction of these curtains or jet streams Cl, C2 and C3, C4 will facilitate the formation of the tornado-like air flows in the two pocket portions 25. As an alternative, the holes or nozzles 31-34 may be situated in another part of the air feed tube 3, e.g. so as to create an increased air pressure in the left part of the interior of the casing (figure 3), whereby air will flow to the right into the respective pocket portions 25 of the casing. Also, the cross-sectional shape of the feed tube 3 may be different from the cylindrical shape as shown, e.g. it may have a rectangular cross section, provided that the feed openings are arranged so as to bring the inlet air into the two pocket portions of the casing.

The pocket portions of the casing may be modified so as to facilitate the formation of tornado-like air flows. An example is shown in figure 4, where each pocket portion 25' is formed by a part of the wall 21', 22', the inwardly directed flange 24' and a semi-cylindrical or curved wall portion 23' therebetween. In this modified embodiment, there will be no sharp corners inside the pocket portions 25' , so the circular tornado-like air flow will be facilitated. In other respects, the embodiment of figure 4 is just like the previous embodi- ment, and the same reference numerals are used for the same structural parts.

A further aspect of the present invention is the possibility of arranging heat exchangers 5 in the interior of the casing 2, preferably in one or both of the pocket portions 25' . The heat exchangers may be in the form of electrical heating elements or, preferably, in the form of pipes 51, 52 for leading through a hot or a cold fluid, such as water or water mixed with some other liquid, e.g. ethanol. Since these heat exchangers 5 are located inside the tornado-like air flow, the thermal exchange will be particularly effective.

Of course, the pipes 5 illustrated schematically in the draw- ings may be connected to non-illustrated sources for hot and/or cold fluids. Also, in such connected conduit systems, there may be control apparatus for controlling the temperature above or below the room temperature, or totally switching off the heat exchangers. The pipes may also by provided with radial flanges or the like in order to further increase the thermal exchange.

Practical experiments have shown that an air supply device 1 as shown in figures 1-3 operates very efficiently. There is of course a net flow of air from the interior of the casing 2 through the supply air opening 4 and into the adjoining part of the room, such net air flow being indicated by the arrow S in figures 1, 3 and 4. However, at the same time, there is a certain flow of air from the adjacent part of the room in- wardly through the supply air opening 4 into the interior of the casing, such a backward air flow being caused by the somewhat lower static pressure caused by the high velocity air flow in the air curtains C1-C4 and the tornado-like air flows T. These oppositely directed air flows (see arrows B in figures 3-4) will cause an irregular, turbulent air flow in the supply air opening 4. It should be noted that the arrows S and B are schematic and do not necessarily illustrate the exact air flow in the region outside the air supply opening 4.

Nevertheless, it has turned out that the net air stream from the air supply device 1 has a strong momentum, although the air velocity is not very great, and the somewhat diffuse or turbulent air stream S will not be disturbing to any person being present in the immediate vicinity of the air supply device. Rather, the net air flow will be comfortable to human beings, and there will also be a mixing of the ambient room air and the inlet air inside the casing. So, in case the inlet air is colder or warmer than the room air temperature, there will be some equalization of the temperature inside the casing. In particular, in the case of supplying cool air when the room air is warm, the air stream S flowing into the room will be somewhat pre-warmed before leaving the supply air opening 4. Accordingly, the ambient room air will also participate in the thermal exchange, by way of the backward flow of air B through the supply air opening 4.

In the manner described above, the main object of the inven- tion will be achieved by the air supply device 1 described above, in particular so as to obtain a comfortable climate in the room.

In figures 5, 6 and 7, some examples of arranging the air supply device are shown. In figure 5, the second wall 22 of the casing 2 is secured to a wall W of the room, with the longitudinal direction of the casing 2 being oriented horizontally, at some distance above the floor F of the room; and the supply air opening 4 being directed downwards against the floor F. It is also understood that instead of the second 22 wall being secured to the wall, the first wall 21 of the casing 2 can be secured to a wall so that the supply air opening 4 is directed downwards against the floor F. The distance between the supply air opening 4 and the floor F can be approximately 100 mm for good performance of the air supply device, but other distances are possible, which is understood by the skilled person.

In figure 6, the air supply device 1 is mounted standing on the floor F adjacent to a wall W with its fourth side wall 26 secured to the wall. In this case, the elongated supply air opening 4 (non visible) is oriented in the vertical direction .

In figure 7, the air supply device 1 is mounted in a chamber or channel 6 underneath the floor surface. There is an extended portion 7 of the chamber adjacent to the supply air opening 4. The supply air will be passed through the extended portion 7 of the chamber through an upper grid 8.

The air supply device according to the invention may be modified in many ways within the scope of the appended claims. There may be more than two rows of holes or nozzles 31-32 and 33-34 on each side of the outlet air opening 4. The heat exchanger or exchangers 5, if any, may be arranged differently, e.g. on the other side of the feed tube 3 (to the left in figure 3) .

The feed tube 3 may be integrated with the casing, so that it will be partly defined by a casing wall, e.g. the fourth wall 26 as indicated above. The feed tube may alternatively have a different cross-sectional shape. The supply air opening 4, defined by flange walls portions, may be slightly inclined (upwards or downwards in figure 3) .

Also, within the air supply device 1, further equipment or components may be arranged, such as control equipment, air flow regulating devices, temperature sensors, or the like.

As to the mounting of the air supply device 1, it can be located and positioned in any manner, as desired, e.g. at some different structural part of the room, for instance at a pillar or a partition or the like.

Claims

1. An air supply device (1) for blowing air into a room, comprising an air feed tube (3), a box-like casing (2) accommodating said feed tube (3) and having first and second side walls (21, 22) and a third wall (23, 23') therebetween, where a supply air opening (4) is located, and feed openings (31, 32, 33, 34) in said feed tube (3) for feeding supply air via the interior of the casing (2) and via said supply air opening (4) into said room, said supply air in said interior of the casing being caused to flow in a circular pattern and to mix with room air being sucked in through said supply air opening (4) before it is blown into said room, c h a r a c t e r e r i s e d in that - said casing is provided with two opposite, parallel, longitudinally extending side pocket portions (25) being formed inside the casing (2) on each side of said supply air opening (4), adjacent to said first and second side walls (21, 22), respectively, and - said feed openings (31, 32, 33, 34) in said feed tube (3) are located and configured so as to bring the inlet air to flow into said side pocket portions (25) and cause a tornado-like air flow (T) in each side pocket portion (25) , - whereby the air circulating with high velocity in said tornado-like air flow (T) interacts in said side pocket portions with air sucked in from the room, whereas the net air stream (S) flowing out through said supply opening (24) will be irregular and turbulent and yet steady with a strong momentum.

2. An air supply device as defined in claim 1, wherein said feed openings (31, 32, 33, 34) in said feed tube (3) comprise at least two rows of air nozzles (31, 32, 33, 34), each row extending longitudinally along the casing (2) and the nozzles being directed obliquely towards at least one of said first and second side walls (21, 22) .

3. An air supply device as defined in claim 2, wherein said at least two rows of air nozzles (31, 32, 33, 34) are configured to cause an air curtain (Cl, C2, C3, C4) striking at an oblique angle against said first and second side walls (21, 22) of said casing (2), whereupon the flowing air is deflected and transformed into said tornado-like air flow (T) in the associated side pocket portion (25) .

4. An air supply device as defined in claim 2, wherein said rows of air nozzles (31, 32, 33, 34) comprise, on each side facing said first and second side walls (21, 22) of the casing (2), at least two parallel rows (31, 32 and 33, 34) of nozzles .

5. An air supply device as defined in claim 1, wherein each of said side pocket portions (25) is defined by: a part of said first or second side wall (21, 22), a part of said third wall (23) , and a flange wall (24) extending along said supply air opening (4) inwardly from said third wall (23) into the interior of said casing (2) .

6. An air supply device as defined in claim 1, wherein each of said side pocket portions (25' ) is at least partly defined by a curved wall portion (23') merging with said first or said second side walls (21', 22'), respectively.

7. An air supply device as defined in claim 1, wherein a longitudinal heat exchanger (5) is arranged in at least one of said side pocket portions (25) .

8. An air supply device as defined in claim 7, wherein said longitudinal heat exchanger (5) comprises longitudinally extending pipes (51, 52) for leading through a hot or a cold fluid.

9. An air supply device as defined in claim 1, wherein said casing (2) comprises a fourth wall (26) also facilitating mounting the supply air device at a wall (W) of said room.

10. An air supply device as defined in claim 9, wherein said supply air opening (4) in said casing, upon mounting the device at a wall (W) of said room, extends substantially in a horizontal direction.

11. An air supply device as defined in claim 9, wherein said supply air opening (4) in said casing, upon mounting the device at a wall (W) of said room, extends substantially in a vertical direction.

12. An air supply device as defined in claim 1, wherein said casing (2) is mounted with one of its side walls being substantially flush with or located slightly below a floor portion (F) of said room, there being an extended chamber (7) adjacent to said supply air opening (4), said extended chamber (7) being provided with an upper grid (8) for passing through the inlet air into the room.

13. An air supply device as defined in claim 12, wherein said grid (8) is arranged in a plane being flush with said floor portion (F) of the room.