EP0563509B1 - Air outlet for air treatment installations - Google Patents

Abstract

An air outlet for air-treatment installations is provided with a distribution box (1) which is connected, via one or more incoming-air openings (6) arranged in the floor (4) of the distribution box (1), to a cavity floor (8) which guides the incoming air. On the outlet side, the air outlet includes a honeycombed grating (9) which has honeycombs which are preferably directed upwards obliquely in the direction of flow and which are surrounded on both sides by a perforated sheet (10, 11) and connected to these sheets to form a component which can be removed from the distribution box (1). <IMAGE>

Description

The invention relates to a source air passage for ventilation systems according to the preamble of claim 1.

Such source air passages (DE-PS 36 40 706) must introduce the supply air over a large area in the floor area with low air speeds and in the same direction. Furthermore, the source air passages require a certain pressure loss at the inlet in order to achieve a uniform loading of several passages when these are supplied with supply air from the same cavity floor. In the interior, it is again important that the outflow cross-section facing the space to be air-conditioned is applied uniformly, so that no local speed peaks occur in the space. It is known from EP-OS 0 311 934 to connect several chambers in series for this purpose and to realize the pressure loss or the uniform distribution of the supply air through a perforated plate or a honeycomb grid. However, the construction of two chambers is expensive and requires a relatively large amount of space. Furthermore, cleaning the source air passage inside is difficult and the use in thin room partitions is only possible to a limited extent.

Source air outlets are often installed in connection with air-guiding double floors (DE-PS 36 40 706) and here in particular with cast vaulted floors. The air connection piece of the source air diffuser is cast in and must be positioned very precisely so that the attached source air diffuser is later seated in the right place. An adjustment option for construction tolerances and assembly inaccuracies in the source air passage would save working time for assembly and modification work.

In certain applications, source air outlets must be designed so that they can be individually blocked. Motorized butterfly valves are usually installed in the supply line for this purpose. In the case of cast vaulted cavities, however, this solution cannot be used. The motor and the butterfly valve should be in the housing of the displacement air diffuser here.

Real source air systems, i. H. Systems without induction of warmer room air in the air outlet are limited to around 4 Kelvin in the difference between the supply and room air temperatures, so that the temperature difference between the head and foot area remains within 2 Kelvin for reasons of comfort. In order to dissipate higher cooling loads, the temperature difference cannot be increased further, only the supply air volume flow. However, since the air velocity in the outflow cross section of the source air diffuser must be below 20 cm / s in the comfort range, only an increase in the outflow area is usually possible over the height of the source air diffuser. However, this leads to the unpleasant side effect that a decrease in the air speed in the upper region occurs due to the necessary lower temperature of the supply air and the resulting higher density in the course of the flow. In the foot area, values twice as high as before the source air outlet can be achieved, which can lead to drafts especially in summer when wearing open shoes.

A further requirement for a source air passage is made in the area of acoustics. If source air outlets in adjacent rooms are connected to the same air-bearing cavity floor, there is a risk of noise being transmitted by air. The sound then passes from one room into the neighboring room via the path of source air passage in the transmission room, cavity floor and source air passage in the reception room. A sound-absorbing lining of the entire cavity floor is usually ruled out for cost reasons.

The invention has for its object to design the known source air passage in such a way that the escaping air reaches the area where the people are staying with a speed distribution that is uniform over the height, and that the possibility of easy accessibility of the distribution box, a reduction in noise transmission, an air barrier and one Adaptation to building tolerances is given.

This version is solved according to the invention in a generic source air passage by the characterizing features of claim 1. Advantageous embodiments of the invention are specified in the subclaims.

Due to the pressure loss of the inner perforated plate, the outflow element according to the invention causes a uniform application to the honeycomb grid acting as a flow straightener. The outer perforated plate creates a backflow effect, which ensures an even air flow within the honeycomb grille. In addition, the outer perforated plate divides the supply air entering the room to be air-conditioned into many individual jets, which rapidly reduce the air speed due to mutual induction. These measures ensure that there is a uniform and low-turbulence displacement flow across the width of the source air passage at the bottom of the occupied area. The increase in speed in the lower region of the flowing air is reduced if the honeycomb of the honeycomb grille is positioned in relation to the vertical. Such an angular position creates an increase in the layer height of the flowing supply air layer in the room to be air-conditioned. At the same time, the initial inclination of the air jets counteracts a downward velocity component, which results from the higher density of the cooler supply air compared to the ambient air and which would lead to an increase in the flow velocity in the lower region of the flowing air layer. The outflow element can be carried out completely in a simple manner Removable from maintenance and assembly work, so that the units arranged inside the distribution box z. B. trained according to claims 6 and 7 shut-off are easily accessible. Due to the features of claims 8 and 9, tolerances and inaccuracies in the construction area and in the assembly of the displacement air passage can be compensated. A noise transmission between rooms via a plurality of distribution boxes connected to the same floor space can be reduced in that the guide element designed according to claim 11 directs the supply air before exiting the outflow element against the rear wall of the distribution box provided with a sound-absorbing material.

Fig. 1

im Querschnitt teilweise einen zu klimatisierten Raum mit einem Quelluftdurchlaß,

Fig. 2 und 3

den zu klimatisierenden Raum gemäß Fig. 1 mit einem anderen Quelluftdurchlaß,

Fig. 4

den Blick in das Innere eines Quelluftdurchlasses,

Fig. 5

den Schnitt V - V nach Fig. 4,

Fig. 6

die Einzelheit Z nach Fig. 5,

Fig. 7

die Strömungsverhältnisse im Bereich des Austrittes eines Quelluftdurchlasses,

Fig. 8

den Schnitt V - V nach Fig. 4 mit einer anderen Ausführungsform,

Fig. 9

die Einzelheit Y nach Fig. 3,

Fig. 10

in perspektivischer Darstellung einen Quellendurchlaß in einer anderen Ausführungsform,

Fig. 11

die Einzelheit X nach Fig. 1 gemäß einer anderen Ausführungsform

Fig. 12

den Längsschnitt durch Fig. 11,

Fig. 13

den Blick in das Innere eines Quelluftdurchlasses gemäß einer weiteren Ausführunsform,

Fig. 14

den Schnitt XIV - XIV nach Fig. 13,

Fig. 15

den Schnitt XV - XV nach Fig. 13 und

Fig. 16 und 17

den Schnitt XV - XV nach Fig. 13 für weitere Ausführungsformen.

Several embodiments of the invention are shown in the drawing and are explained in more detail below. Show it:

Fig. 1

partly in cross-section an air-conditioned room with a source air passage,

2 and 3

1 to be air-conditioned according to FIG. 1 with a different source air passage,

Fig. 4

the view inside a source air diffuser,

Fig. 5

the section V - V of FIG. 4,

Fig. 6

the detail Z according to FIG. 5,

Fig. 7

the flow conditions in the area of the outlet of a source air passage,

Fig. 8

4 the section V - V according to FIG. 4 with another embodiment,

Fig. 9

the detail Y according to FIG. 3,

Fig. 10

a perspective view of a source passage in another embodiment,

Fig. 11

the detail X of FIG. 1 according to another embodiment

Fig. 12

the longitudinal section through Fig. 11,

Fig. 13

the view into the interior of a source air diffuser according to a further embodiment,

Fig. 14

the section XIV - XIV of FIG. 13,

Fig. 15

the section XV - XV of Fig. 13 and

16 and 17

the section XV - XV of FIG. 13 for further embodiments.

In the floor area of a room to be air-conditioned, a source air passage is arranged which contains a distribution box 1. The distribution box 1 is delimited by a ceiling 2, a rear wall 3, a floor 4 and on the outlet side by an outflow element 5. The ceiling 2 and the rear wall 3 can be provided on the outside with a heat-insulating material 28. In the floor 4, one or more supply air openings 6 are provided, which are connected to a cavity floor 8 having one or more through openings 7. The distribution box 1 of the source air passage is supplied with supply air via this cavity floor 8. The source air passage is arranged according to FIG. 1 in the area of the parapet of the window wall. The source air outlet can also be accommodated in room partitions, in the cupboard base area or on and around columns.

The outflow element 5 (FIGS. 5, 6) is formed by a honeycomb grid 9, acting as a rectifier, made of honeycombs of round, square or polygonal cross section, which is delimited by an inner perforated plate 10 and an outer perforated plate 11. The perforated plates 10, 11 form with the honeycomb grid 9 a component that can be removed from the distribution box 1. The free cross section of the holes in the perforated plates 10, 11 is smaller than the free cross section of the honeycomb of the honeycomb grid 9. The longitudinal axis of the honeycomb of the honeycomb grid 9 is directed obliquely upward in the direction of flow of the supply air and forms an angle with the vertical of less than 90 ° . This results in a supply air flow that points obliquely upwards into the air-conditioned room. As a special case, the angle that the honeycomb axis forms with the vertical can also be 90 °. This can be advantageous if the source air passage is only low and if there are small temperature differences between the supply air and the room air. Instead of a honeycomb grid, a nonwoven fabric or a porous plate, for example made of foam, can also be used as a rectifier.

7 shows the flow conditions which occur immediately before and after the outflow element 5 according to the invention. In the distribution box 1, which is characterized by the area A, the supply air flows in obliquely and unevenly. In region B, the flow within the honeycombs of the honeycomb grid 9 is rectified. Immediately behind the outlet from the outflow element 5, a swirl takes place in the area C, which is followed by the area D with a low-turbulence displacement flow.

1 to 3 show the flow profiles of the emerging displacement flow for various outflow elements. The length of the arrows gives a measure of the size of the flow velocity and the direction of the arrow indicates the direction of flow. The speed profile generated directly by the honeycomb grille of the honeycomb grille directly behind the outflow element is, according to FIG. 1, uniform over the height of the air flow and has an overall upward direction. Since the supply air has a lower temperature than the room air and therefore has a higher density, there is a speed component in the direction of the floor. Due to the upward outflow, the downward velocity component is effectively counteracted by the higher density of the supply air. As the 2nd and 3rd flow profiles in Fig. 1 show, the obliquely upward flow direction changes into a horizontal flow direction due to the higher density of the supply air. In the further course, the flow speed of the supply air in the foot area increases again somewhat. When entering the lounge area, the flow speed in the foot area is greater than in the upper air layer, but overall the speed distribution is quite uniform over the height of the flowing air layer. The somewhat higher flow velocity in the area near the ground is, however, significantly lower than in the case of a honeycomb grid with horizontal honeycombs under otherwise identical conditions, as is shown in FIG. 2. With such an outflow element, the Flow speed in the lower part of the flowing air layer constantly, because the supply air has a lower temperature and thus a higher density than the room air. When entering the stay area (4th speed profile), the flow speed in the lower area can be more than twice as high as in the upper area. The honeycomb grille with horizontal honeycombs remains limited to applications in which the source passage has a low overall height and in which there is a small temperature difference between supply air and room air.

The diameter of the holes in the perforated plates 10, 11 is matched to the desired pressure loss. When choosing the hole diameter and the hole division for the inner and the outer perforated plate 10, 11 and when selecting the diameter of the honeycomb of the honeycomb grid 9, care must be taken that all honeycombs are acted upon. This is the case if the honeycomb diameter or the clear width of the individual honeycomb is equal to or greater than the hole division. It is not important for the practical implementation that, as shown in FIGS. 6 and 7, a honeycomb is assigned to each hole of the inner perforated plate 10. The same applies to the outer perforated plate 11. It may well be that the wall of a honeycomb comes to rest in the area of a hole. This does not affect the air flow pattern in the room to be air-conditioned.

In the outflow element 5 shown in FIG. 9, the holes 12 in the upper region of the outer perforated plate 11 are designed like nozzles, while the holes 13 in the lower part are simple openings. By choosing the diameter of the holes 12, 13, it is possible to apply air to the honeycomb of the honeycomb grid 9 in different ways. In this case, the honeycombs in the area of the holes 12 formed as nozzles are preferably acted upon higher than the honeycombs in the lower area of the honeycomb grid 9.

With the aid of the outflow element 5 shown in FIG. 9, the flow distribution shown in FIG. 3 is established. In the upper area, the flow rate of the exiting air is higher due to the higher loading of the upper honeycombs of the honeycomb grid 9. This counteracts the drop in flow velocity caused by the low temperature of the supply air in this area, so that when entering the lounge area, the flow rate over the height of the flowing air layer is almost the same in spite of the constant increase in the flow rate in the foot area.

4 and 5, the supply air opening 6 is followed by a supply air connector 14 projecting into the cavity floor 8. A shut-off device is located inside the distribution box 1 to block the source air passage, if necessary. This shut-off device consists of a cover 15 which is connected to the end of a threaded rod 16 designed as a rising spindle. A drive motor 17 engages the threaded rod 16 and is fastened to the ceiling 2 of the distribution box 1 via a bracket 18.

Particularly in the case of long displacement air passages, the installation of perforated disks 19 transversely in the distribution box 1 can influence the action of the air volume flow of the outflow element 5. This can be particularly useful in the corner areas of rooms if the source air diffusers meet at right angles there and the air velocity would increase.

Another shut-off device is shown in Fig. 8. This shut-off device consists of a perforated plate cylinder 20 which is placed on the supply air connector 14. The perforated plate cylinder 20 is surrounded by a solid wall cylinder 21 which is vertically adjustable. The adjustment is carried out via a threaded rod 16 and a drive motor 17. This type of shut-off device is recommended if, in particular with long displacement air passages with only a supply air nozzle requires a more uniform action on the source air passage and in particular the outflow element. The hole pattern of the perforated plate cylinder 20 is chosen so that a corresponding adaptation to the desired pressure loss and a desired air distribution in the interior of the distribution box 1 is achieved.

In order to be able to compensate for tolerances in the construction area and when installing the supply air connector 14, the supply air connector 14 is provided with a right-angled edge flange 22. The outer diameter of the edge flange 22 is larger than the cross section of the supply air opening 6 in the bottom 4 of the distribution box 1. The supply air connector 14 is displaceable relative to the distribution box 1 and temporarily receives an insert 23 made of rigid foam during assembly. When installing the supply air connection 14 in the cavity floor 8, the procedure is such that the insert 23 is inserted into the supply air connection 14 and this is fastened to the supply air connection 14 on the raw concrete ceiling 29. The inlet air connection 14 can now be adjusted in height on the insert 23 to the required dimension of the cavity floor 8. After the cavity floor 8 has been cast, the insert 23 is removed again. Then the distribution box 1 is placed on the edge flange 22 of the supply air connector 14 and aligned, displacement in two planes being possible. Finally, the distribution box 1 is screwed to the edge flange 22.

Another embodiment for compensating for construction tolerances is shown in FIG. 10. Here, a continuous slot 24 is arranged as a supply air opening in the bottom 4 of the distribution box 1. The slot 24 can also be interrupted by webs. This design of a slot-shaped supply air opening in the bottom 4 of the distribution box 1 of the source air passage is particularly suitable for narrow room partition walls. The distribution box 1 is sealed off from the cavity floor 8 by a circumferential seal 25. If the area of the supply air opening designed as a slot 24 is smaller than the area enclosed by the circumferential seal 25, the inside Cavity floor 8 existing passage opening 7 for the supply air does not exactly match the slot-shaped supply air opening in the floor 4 of the distribution box 1. This also allows for adaptation to tolerances by moving in two planes.

The embodiment shown in FIGS. 13 to 15 serves to reduce the possible transmission of noise between neighboring rooms via the source air passages and a common cavity floor 8. The supply air is fed via the supply air connection 14 through the supply air opening 6 to the distribution box 1, the rear wall 3 and the ceiling 2 of which are provided with a sound-absorbing material 26. Between the extension of the supply air opening 6 and the outflow element 5, a guide element 27, which is curved as a half-cylinder shell, is installed in the distribution box 1. The closed side of the bowl-shaped curved guide element 27 is the outflow element 5 and the open side is facing the rear wall 3. The guide element 27 extends over the height of the distribution box 1 between the floor 4 and the ceiling 2. The supply air entering through the supply air opening 6 is directed by the guide element 27 onto the rear wall 3 provided with the sound-absorbing material 26. The deflection extends the path of the sound and the sound waves are brought into contact with the sound-absorbing material 26, most of which is absorbed.

The guide element 27 can consist of sound-absorbing material or of a sheet metal coated with sound-absorbing material. Instead of providing the entire ceiling 2 with a sound-absorbing material 26, only the area of the ceiling 2 which is above the supply air opening 6 can also be lined.

As shown in FIGS. 16 and 17, the guide element 27 does not necessarily have to be semi-cylindrical, but can also have a different geometric shape. The guide element 27 according to FIG. 16 is angled, while the guide element 27 according to FIG. 17 has the shape of a stepped shell. In both cases, the closed side faces the outflow element 5 and the open side faces the rear wall 3. Priority to the shape of the shell is its orientation and thus the extension of the sound path and the enlargement of the sound absorption area.

Claims (12)

1. Source-air passage for room-air systems having a distributor box (1) which is connected, via one or more incoming-air ports (6) arranged in the bottom (4) of the distributor box (1), to a cavity floor (8) carrying the incoming air and which is provided with a straightener on the outlet side, characterized in that the straightener is surrounded on both sides by perforated plates (10, 11) and is connected to these to form a structural part removable from the distributor box (1).
2. Source-air passage according to Claim 1, characterized in that the straightener consists of a honeycomb lattice (9).
3. Source-air passage according to Claim 2, characterized in that the honeycombs of the honeycomb lattice (9) are directed obliquely upwards in the direction of flow.
4. Source-air passage according to one or more of Claims 1 to 3, characterized in that, in the upper part of the perforated plate (11) arranged on the outlet side, the holes (12) are of nozzle-like shape.
5. Source-air passage according to one or more of Claims 1 to 4, characterized in that an incoming-air connection piece (14) projecting into the cavity floor (8) adjoins the incoming-air port (6) in the bottom (4) of the distributor box (1).
6. Source-air passage according to Claims 1 to 5, characterized in that the incoming-air port (6) can be closed by means of a vertically adjustable cover (15) which, on the side facing the distributor box (1), is connected to a rising spindle (16), on which a drive (17) engages.
7. Source-air passage according to Claim 5, characterized in that a perforated-plate cylinder (20) is placed onto the incoming-air connection piece (14) inside the distributor box (1) and is surrounded by a solid-wall cylinder (21) which is vertically adjustable via a rising driven spindle (16).
8. Source-air passage according to Claim 5, characterized in that the incoming-air connection piece (14) is provided with a rectangular edge flange (22), the outer limitation of which is larger than the cross-section of the incoming-air port (6), and in that the incoming-air connection piece (14) is displaceable relative to the distributor box (1) and can be aligned on the rough-concrete ceiling (29) via an insert (23) which is temporarily insertable into the incoming-air connection piece (14).
9. Source-air passage according to one or more of Claims 1 to 4, characterized in that the incoming-air port is designed as a slit (24), in that the bottom (4) of the distributor box (1) rests on the cavity floor (8) via a peripheral gasket (25) surrounding the slit (24) with clearance, and in that the area enclosed by the gasket (25) is larger than the cross-sectional area of the slit (24).
10. Source-air passage according to one or more of Claims 2 to 9, characterized in that the clear width of the individual honeycomb of the honeycomb lattice (9) is equal to or larger than the hole spacing of the holes of the perforated plates (10, 11).
11. Source-air passage according to one or more of Claims 1 to 10, characterized in that the rear wall (3) of the distributor box (1) is provided with a sound-absorbing material (26), and in that there is arranged in the distributor box (1), between the vertical prolongation of the incoming-air port (6) and the outflow element (5), a guide element (27) which is curved in a dish-like manner, and of which the closed side faces the outflow element (5) and the open side faces the rear wall (3).
12. Source-air passage according to Claim 11, characterized in that the guide element (27) is provided with a sound-absorbing material (26) or consists of this.

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