FI90466C - Method and distribution device for introducing air into a room - Google Patents

Abstract

A method of introducing air into a room by passing supply air (A) into a distribution device (1) ending in the room (2) and by blowing the air from the distribution device through air supply openings (8, 9) into the room. In order to control the introduction of air even when the supply air is considerably warmer than the room air, the supply air is introduced into the distribution device selectively through two separate independent flow paths (4, 5) into the air supply openings, whereby the supply air is subjected to flow conditions required for heating at the air supply openings (8) of one flow path and correspondingly to flow conditions required for cooling at the air supply openings (9) of the other flow path. A distribution device carrying out the method comprises at least two separate alternative flow ducts (4, 5) for supply air, the flow ducts being provided with separate air supply openings (8, 9) which provide different flow conditions in the separate flow ducts.

Description

1 90466

The present invention relates to a method for introducing air into a room, according to which 5 - the supply air is led to a distributor entering the room and to different supply air vents, and - the supply air is subjected to different supply air conditions at the supply air inlets of each flow path than at the air inlet openings of the other flow paths.

15 In order to bring air into the room, a variety of devices have been developed that can be roughly divided into three main groups:

With so-called mixing air distributors, air is usually introduced into the upper part of the room from a single point at a high rate through various slots, nozzles or openings. The air flowing from them draws in and mixes with a large amount of ambient room air. The air mass of the entire room is thus moved and mixed to a homogeneity of both temperature and impurity concentration.

Due to the high flow rate, a disturbing sound is easily generated. Large air jets are difficult to control. If the air speed is too high, annoying traction will occur. If, on the other hand, it is too small, easily dead areas are created in the room 30 where the air does not change. The control of Låm poles is hampered by the effect of thermal forces despite mixing with the air jet. If the supply air is warmer than the room air, the air jet bends upwards, so that the air at the bottom of the room does not change. If the air is cold, it bends downwards and causes traction. Controlling the room patient by controlling the supply air temperature is thus only possible to a limited extent. Also, the airflow cannot be very much reached without causing the disadvantages described above.

In the so-called displaceable air distribution, the air is introduced at low speed directly into the living area via a relatively large surface.

Traction and sound problems are usually avoided if the 10 supply and room air temperatures are Saina. If the temperature difference rises to 2-3 degrees, thermal forces begin to control the flow. When the supply air is colder than the room air, the flow "drops", the velocity increases due to thermal forces and draft is created at floor level. Since there is no air jet that draws in the room air, the moving air mass is small and the flow is therefore sensitive to disturbances.Convection flows, air-moving machines, movement of people, various flow obstructions, etc. may control the air flow. This can result in poor local ventilation, and airflow can be achieved over a wide area without inconvenience.

Recently, the so-called active displacement, which eliminates some of the weaknesses of displacing air distribution. The air distribution is spread over a large surface. Air flows into the room from small nozzles at a high speed of 30 d and mobilizes a large mass of air. When the air jet from the small nozzle is small, no noise nuisance occurs despite the high speed. The speed of the air in a small shower decreases quickly, so traction is not easy. When a large air mass is in motion, the flow is not affected by the flow as well as locally, so ventilation throughout the room is even. Due to the high mixing ratio of the supply and room air, the temperature differences are equalized, so that even cold supply air can be introduced into the oles-5 coil area by the "fall" of the flow. There is still no floor draft with a temperature difference of 15 degrees.

However, if the supply air is considerably warmer than the room air, even a small temperature difference after a strong mix will cause the air to rise out of the living area.

Airflow can be achieved over a wide range. Active displacement is thus very well suited for cooling, but to a limited extent. This method of distributing ilitian is described in FI patent publications 79,608, 15,73,513, 72,800 and 71,417.

The object of the present invention is to provide a method which eliminates the above-mentioned drawbacks and, in particular, enables the active operation of active displacement even when the supply air is considerably warmer than room air. The room temperature can be completely controlled and escorted. This object is achieved by the method according to the invention, which is characterized in that the supply air is optionally led through one or more separate independent flow paths.

The invention is based on the idea that the supply air is led from the distributor to the room along two different optional flow paths, so that different inflow conditions are generated for the supply air by means of different inflow nozzles depending on which flow path the air is blown into. One flow path can be used in a heating situation and the other in a cooling situation. When no heating or cooling is required, the supply air can be led partly along both flow paths.

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The invention is particularly suitable for active displacement, but it can also improve the properties of other air distribution methods.

The invention also relates to an air distribution device for applying the method described above. This air distribution device is characterized in that the distribution device has shut-off means for separating the flow channels from each other, and that each flow channel is formed as independent air distribution devices which operate simultaneously together or separately.

The basic idea of the manifold is that the inlet air openings, for example nozzles, are divided into at least two separate groups to which the supply air can be led through separate flow channels. Thus, the number and orientation of the nozzles, the air flow rate in the nozzles, and even the size and shape of the nozzles may be different in each group. Two or more different air distribution systems are obtained from the same air distribution device, the characteristics of which can change almost steplessly from one system to another.

The invention will be described in more detail below with reference to the accompanying drawing, in which Figures 1 and 2 show an embodiment of a dispenser according to the invention in a side view and a section along the line II-II in Fig. 1, Figures 3A and 3B schematically show air blown into a room caused by the flow pattern in the room in the cooling situation and the corresponding heating situation, and Fig. 4 shows the second embodiment of the distributor in a side view.

The air distributor shown in Figures 1 and 2 draws an elongate inlet pipe 1 connected at its main end to a supply air supply system A not shown and extending into the air-conditioned room 2. The pipe is mounted horizontally above the living area. The inlet pipe is divided by a central spacer plate 5 3 into two longitudinal halves, which form two mutually isolated flow channels 4 and 5, which terminate in a closed end plate 6 of the inlet pipe. The interchangeable damper 10 is pivotable between two aria positions, in which the interchangeable damper alternatively completely closes one of the flow channels. The damper can also be set to the selected positions where both flow channels are partially open. It is essential that the flow direction of the flows of the upper flow channel 15 and the lower flow channel of the inlet pipe is opposite, i.e. when the flow of the second channel closes, the flow of the second channel opens. The replacement damper can be manual or connected to a suitable damper.

A large number of nozzles 8 are mounted on the jacket surface of the upper flow channel 4 of the inlet pipe, which direct the supply air rainily into the room. Numerous nozzles 9 are also mounted on the jacket surface of the lower flow channel, which are also mutually parallel. The nozzles of the upper channel are smaller in flow openings than the nozzles of the lower channel.

Figures 1 and 2 show the operation of the distributor in a cooling situation, i.e. when the supply air A is colder than the room air. In this case, the exchange damper 7 is bent 30 to close the lower flow channel 5, so that the supply air flows into the room only through the nozzles 8 of the upper flow channel 4.

Figure 3A schematically shows a flow pattern generated in a room in a cooling situation. The air jets B emanating from the upper nozzles 8 of the inlet pipe 35 are directed at the top and sides and attract a so-called bottom-down pressure. induction air and mix with it. Because the air in the showers is colder than the environment and therefore heavier, the showers tend to bend down. Below the inlet pipe there is a small vacuum due to the jets, which tends to bend down the inverted flow, if there are no longer differences in temperature and density, to the side and back upwards. The forces acting in different directions give rise to the double-circuit flow according to Fig. 3A, in which the main flow direction is up at the center and down at the edges. Although the flow rates are very low, they can be experimentally demonstrated. As with forced vortex currents in general, the vortex is very stable relative to the magnitude of the impulse it generated and recovers very quickly to its original shape after hairide.

The distributor still works as described above, even when the supply air is slightly warmer than the room air. In equilibrium, the vacuum below the inlet pipe is 20 equal to the thermal lift caused by the density difference. If the temperature difference increases, the flow bends upwards and the supply air no longer enters the living area. The situation is complicated, as the temperature difference decreases, the stability of the swirls decreases. In this case, even a relatively small shark, flow obstruction, etc. may completely change the nature of the currents.

When the supply air is warmer than the room air, the exchange damper 7 is turned to the position shown in broken lines in Fig. 1. The entry of the supply air to the upper flow duct 4 is prevented and the supply air flows into the room only from the nozzles 9 of the lower flow duct 5. The air jets C are directed downwards and draw the room air from above the inlet pipe. Thermal forces bend the showers upwards. If the flow pulse is appropriately selected, the flow pattern shown in Figure 3B is formed.

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If the nozzles 8 and 9 of both flow channels are similar, the impulse can only be influenced by changing the number of the nozzles 9 of the lower channel, whereby the flow rate in them changes. In order for the air of the laminate 5 to reach the residence area, the impulse and flow rate in the nozzles 9 must generally be clearly higher than in the upper channel nozzles 8, i.e. the lower nozzles 9 must be less than the upper nozzles 8. In the air distributor type 10, the nozzle 9 advantageously also their trend. As the volume changes, the circular sector with nozzles decreases and the jets are directed more and more centrally downwards.

However, the flow rate in the lower channel nozzles 9 cannot be increased without restrictions: the pressure drop or the sound level easily becomes too high. This problem can also be solved in the system according to the invention by choosing the nozzles 9 to be of a different type than the nozzles 8, so that the impulse of the nozzles 9 and in particular 20 ns. throw length is greater than nozzle 8.

For reasons of manufacturing, among other things, it may be advantageous for the pitSa nozzles 8 and 9 to be similar. The flow is obtained to the desired type by adding a few large nozzles to the nozzles 9 of the lower channel, which act as carrier jets and take the air into the living area. Such a solution is also advantageous in the sense that the mixing ratio of supply and room air remains high.

If the nozzles 9 of the lower channel have to be dimensioned for a large heating power and thus a large temperature difference, which must be achieved from zero to maximum power, the flow from the nozzles 9 may be too strong and cause draft in the living area when the temperature difference is small. The dispensing device is also made to function properly in the stables by fastening a small part of the air 8 90466 by means of an exchange damper 7 through the nozzles 8 of the upper channel.

The air flow and thus also the speed in the lower channel nozzles 9 decreases, whereby the pulse and throw length of the air jet im-5 also decrease. In addition, the slow-flowing supply air from the nozzles 8 is drawn into the mixing air by the air jets of the nozzles 9, whereby the temperature of the air in the jet rises and the thermal buoyancy tends to slow down the downward jet 10 more strongly. In addition, the flow from the nozzles 8 in the opposite direction slows down the flow from the nozzles 9 and thus reduces the jet pulse and throw length. In this way, the flow field can always be modified in such a way that the supply air flushes the entire residence area without causing a harmful draft.

The embodiment of the distributor shown in Fig. 4 differs from the one shown only in that the closing flow means of the different flow channels 4, 5 of the inlet pipe 1 is the so-called butterfly damper 10. This damper encloses two semicircular plates fixedly perpendicular to each other and pivotally mounted on a baffle plate perpendicular to it. The damper 10 operates in the same way as the replacement damper 7 described above.

The drawings and the related explanation are only intended to illustrate the idea of the invention. The details of the method and dispenser according to the invention may vary within the scope of the claims. The inlet pipe of the distributor may have a rectangular cross section myds, an oval, etc., and the ratio of the length to the diameter 30 may vary. The spacer plate can be angular, curved, etc. It also does not have to be longitudinal in the longitudinal direction of the pipe centerline or the sides of the rectangular pipe. The tubes are drawn straight, but they can also be conical and may have shrink pieces 35, etc. The replacement damper can be, for example, a guide wing 9 9 Π A 6 6 din. The inlet openings of the inlet pipe can be mere openings or holes or the like instead of nozzles.

Instead of a swiveling damper, a solution with a guide plate 5 fixedly connected to the partition plate 3 can be used. The VHl plate is mounted so that it rotates around the center line of the pipe 1. By turning the baffle plate 180 degrees, the supply air can be directed to either the nozzles 8 or 9. The weakness of this solution is that the air cannot be partially directed to the nozzles 8 and 9 without substantially changing the direction of the air jets and the flow field generated by them. The bearing of large, often many meters long partitions is difficult and becomes considerably more expensive than the simple sheet 7 according to Fig. 1. The shape of the pipe 1 is also limited.

If the baffle plate 3 is an arc of a circle whose rain is slightly less than that of the pipe 1 and which curves around the center line of the pipe, it forms a barrier plate which can be turned to close either the nozzles 8 or 9. The weaknesses are the same as in the application described above. The advantage is a smaller pressure drop because air flows to the nozzles through the entire cross-section of the pipe 1.

The baffle plate 3 can also be made fixed and the tube 1 rotated around it. The baffle plate may also be outside the tube 1 in this and the previous application.

Claims (9)

1. A method for introducing air into a room, according to which method 5. Inlet air (A) is introduced into a distribution device (1) which opens in the room (2) and - is blown from the distribution device through blow-in openings (8, 9). into the room, wherein - the inlet air (A) is conducted in the distribution device 10 (1) through at least two separate flow waves (4, 5) to different inlet openings (8, 9), and the inlet air is provided at the inlet openings (8, 9) for each flow wave differently inlet conditions (B, C) than the inlet openings for the other flow scales, characterized in that the inlet air (A) is selectively guided through one or more separate independent flow scales (4, 5). 2. A method according to claim 1, characterized in that the inlet air (A) is selectively conducted in a heating situation and in a cooling situation through different flow waves (4, 5). 3. A method according to claim 1, characterized in that the inlet air (A) is conducted partially along each flow wave (4, 5) when neither heating nor cooling is required. 4. Distribution device for introducing air into a room, which distribution device (1) is connectable to a pipe for inlet air (A) and is provided with openings 30 (8, 9) for blowing inlet air into the room (2) and which distribution device (1) has at least two separate flow channels (4, 5) for inlet air (A), wherein the different flow channels (4, 5) are provided with their own inlet openings (8, 9) and the inlet openings 35 (8, 9) are provided provide for the inlet air flowing through different flow channels (4, 5) different inlet conditions (B, C), characterized in that the distributing device has closing means (7; 10.) to separate the flow channels (4, 5) from each other and each flow channel is challenged as a self-contained air distribution device which operates simultaneously or separately. Distribution device according to claim 4, characterized by a pipe, characterized in that the distribution device (1) is divided by an axial dividing wall (3) into two longitudinal flow channels (4, 5) and that in the intermediate wall inlet end there is a closing gate (9; 10), which is pivotal to any of the flow ducts of the inlet air (A) rod. 6. Distribution device according to claim 5, characterized in that the position of the rod damper (9; 10) is adjustable between the rods of the rod passage. Distribution device according to any one of claims 4-6, wherein the inflow openings (8, 9) are formed of nozzles, characterized in that the nozzles (8, 9) of different flow channels (8, 9) are different in size and / or different to their number. Distribution device according to any one of claims 4-7, characterized in that the nozzles (8, 9) belonging to different flow channels (4, 5) are substantially opposite in direction.