A cooling or condensation device with a precooler for the cooling air

Abstract

 For cooling or condensation devices of many kinds, using air as the cooling medium, it is known to precool this air, whether circulating or entering from the ambient atmosphere. The invention proposes to provide an air cooler (1) for this purpose with one or more movable air cooling parts (3), such as packs of spaced apart lamellae over which water is sprayed and caused to flow downwards as a thin film, so that such parts can be moved fully or partially out of and into the path of the air stream to said cooling or condensation device. This makes it easily possible to adapt the air cooling to the particular circumstances at any moment, in particular to temperature differences in the inflowing air between summer and winter, between day and night, and even between sunlight and overcast sky, if desired. There may be an automatic temperature control of such movements. The movable part(s) may be slidable or pivotable, there may be means to enclose the cooling parts when moved and to cause automatic emptying of the cooling fluid such as water therefrom to avoid contamination and freezing.

Description

[0001] The invention relates to a cooling or condensation device with a precooler for cooling the air used as a cooling medium therein.

[0002] It is known to provide cooling or condensation devices for many purposes with a cooler (a precooler) for the air serving as the cooling medium in said device. This cooler can cool fresh air brought in from outside, for example drawn in by the cooling or condensation device, and/or air which has already flowed through said device and is being circulated. The air cooler can be built into the cooling or condensation device and generally works with water which is sprayed and guided over fixed surfaces in the air cooler so that, in contact with the air flowing crosswise through it, it draws heat from it through conduction and particularly evaporation.

[0003] If the available air is for any reason temporarily cool enough for carrying out its cooling or condensation function without pre-cooling, for example for outside air in winter, the air cooler can be switched off, for example by feeding in no water or other cooling medium thereto. Although the throughflow resistance for the air through the pre-cooler need not, relatively speaking, be great, this still takes some flow energy which is then unnecessary but, besides, the air cooler can become soiled by the throughflowing air, in the case of a cooler working with a water film particularly by the fact that the water film which keeps the fixed surfaces clean when in operation, is then absent.

[0004] Sometimes the air cooler can be dismantled with some difficulty and, for example, in winter stored elsewhere, or one can also, through valves and a bypass channel, make the air pass round the cooler to the cooling or condensation device. This means a large amount of work and/or takes up a large amount of space, and it means a complex construction with, for example, large valves etc.

[0005] The object of the invention is to make an improvement herein and produce a device in which the air cooler can be put out of action in a simple and efficient manner. To this end, a device of the type mentioned in the preamble is according to the invention characterized in that said air cooler comprises one or more air cooling parts which are movably connected to a bearing structure of the device, in such a way that such parts can be moved fully or partially out of and into the path of the air stream to said cooling or condensation device.

[0006] This movement of the air cooler can, for example, be controlled by hand. This is suitable in particular if the air cooler is to be converted only a few times a year, for example only for switching it off in winter. Means can also be provided for measuring the temperature of the air used for cooling, and a signalling device can be provided on the movement means for the air cooler, so that the air cooler is moved on reaching a limit temperature. These means can then be operated a greater or smaller number of times per time period, for example even per day, i.e. more frequently if the difference between the limit temperature for switching off and the limit temperature for switching on is made small, and less frequently if the said temperature difference is chosen to be greater.

[0007] The invention also comprises a further development of that principle, as will be described further with reference to two examples of embodiments shown in the drawings, in which:

Fig. 1 is a vertical section of an air cooler according to the invention in a first embodiment, in a plane parallel to the main direction of flow of the air therethrough;

Fig. 2 is a vertical section and view in a plane parallel to that of Fig. 1, near one of the vertical end edges of the cooler;

Fig. 3 is a horizontal section and view through an air cooler according to the invention, in a different embodiment.

[0008] The air cooler 1 of Figs. 1 and 2 has means at 2 to be connected to a cooling or condensation device which can be of any type suitable for the purpose, using air as the cooling medium. This air can exert the cooling or condensation action on a medium which flows therethrough in pipes or chambers shut off from the air, or works with cooling effect on water coming into contact with the air, for example water raining therethrough, or on solid foodstuffs and the like, coming into contact with said air in said cooling device, etc. Such cooling and condensation devices are known in many designs and for many such purposes.

[0009] The air cooler 1 serves to pre-cool air from the environment or from the cooling or condensation device before it is used (again) for said cooling or condensation. For this purpose, the cooler 1 can have in a manner known per se a pack 3 of lamellae (thin plates or sheets) for example having spaced a short distance apart from each other lamellae with corrugations in different directions, over which water is sprayed from above at 4, which flows over the lamellae as a film, while the air flows along them, so that the air is cooled through conduction, but particularly through evaporation of the water. Since such lamellae structures are known in many forms, they need not be described here in more detail.

[0010] The water which flows from the lamellae at the bottom is collected in a tray 5, which in the main direction of flow of the air, indicated in Fig. 1 by horizontal arrows, is longer than the thickness of the pack of lamellae. Said extended tray part is connected to a pump (not shown), for example an immersion pump, the discharge 6 (Fig. 2) of which is connected to an upwardgoing pipe 7 to the spray feed 4.

[0011] The pack of lamellae 3 has a frame 8, which at the narrow vertical ends has rollers 9, which are guided along vertical guide strips 10, fitted in a fixed frame 11, in which the frame 8 is vertically movable. Said frame 8 also has on each of said narrow vertical ends a roller 12, over which runs a strap 13, which at 14 is fixed in the frame 11, runs from there downwards over the roller 12, and from there runs to a winding drum 15 in the top of frame 11, said drum 15 being disposed on the shaft of an electric motor t6. There is preferably one electric motor 16 with a long shaft and a drum 15 near each end.

[0012] When said motor is put into operation to wind the two straps 13 each onto their drum 15, then the pack of lamellae 3 is raised at half the speed of the straps 13 and with in those straps a force of about one quarter of the weight of said pack with its frame 8, water present therein etc. The rollers 9 guide all this along the guide strips 10. Fig. 1 shows the highest raised position of this unit diagrammatically by the dot-and dash-lines for tray 5 in this position. It can be seen from it that the air can then pass through the air cooler chamber unimpeded to the cooling or condensation device connected to it at 2, while the active part of the air cooler is then confined between the closed upright side and end walls 17 and the closed top side 18 of the frame 11, so that it is protected against dust and the weather.

[0013] In order to prevent water from freezing in the cooler in winter, or possibly becoming polluted if it is not used, the cooler must be emptied in this raised position. This can be carried out by operating manually, or automatically under the influence of the lifting, a valve which empties the tray 5 in such a way that the water also flows out of the pump and out of the pipes 4 and 7. Another possibility is shown in Fig. 1: near the bottom end of tray 5, a hose 19 is connected thereto at one end, and leads up to a fixed discharge standpipe 20. In the connection to tray 5, this hose can have an additional bend in a plane perpendicular to the plane of Fig. 1, or also a swivel connection on a nipple at tray 5. When the pack 3 etc. is now raised, hose 19 is moved into the position shown by dot-and dash-lines in Fig. 1., and the tray 5 - and therewith also the pump and the pipe 7 - automatically empties.

[0014] Fig. 3 shows in horizontal section how in the fixed frame 11 of such an air cooler the lamellae packs are divided up into a number of packs 21 of smaller width, each in a frame 22, and each rotatable about a vertical shaft 23, in which the frame 22 can have a trunnion at the top and bottom which is accomodated in a bearing sleeve in the fixed frame 11, and at least one of which can be rotated, for example by means of a sprocket chain wheel disposed thereon and a chain which engages therewith and runs along all packs. Two such chain wheels 24, and such a chain 25, accommodated in a hollow end bar of frame 11, are shown schematically by dot-and dash-lines in Fig. 3. The chain 25 is thrown round the sprocket chain wheels 24 in such a way that on movement of the chain, adjacent packs 21 turn in opposite directions. The chain can be driven by means not shown, by hand or mechanically. In the position shown by solid lines, the packs 21 close the air passage of the air cooler (with direction of flow shown by vertical arrows) off completely, so that all air has to flow through the packs. A sealing strip 26 can be provided for this purpose near the upright frame edges. The packs then lie, as shown, in a zigzag pattern, so that they lie better against each other for such sealing. On movement of the chain 25, the packs 21 turn in opposite directions to the positions shown by 21', in which they impede the air flow as little as possible and are not passed through by air. The water supply, the distribution means for the water over the lamellae etc. are not shown here, but are located in the top o'f the packs 21 and turn with them when the latter are turned. The packs can also, if desired, be placed in intermediate positions, in which the air flows partially through - and partially does not flow through - the packs, and it is precisely for this that the opposite rotation of the packs described above is important. The throughflow resistance of the packs can be so small that the openings between the packs in those intermediate positions do not give a complete short circuit of the air flow through the cooler.

[0015] In tall packs, the downward flow of water can be interrupted to prevent said flow narrowing in a lower zone to a number of more concentrated flows, instead of a uniform film being maintained over the whole surface of the lamellae, and/or in order to prevent too much water from flowing away along the front and rear face out of the packs. For this, interruptions can be provided at one or more points over the height of the packs to collect and redistribute the water.

[0016] Fig. 1, at the top lefthand side, shows schematically a thermometer 31, which by means of a controller 32 controls the motor 16. The controller 32 can operate with a wide or a narrow temperature range, in other words, when the pack reaches a low outside temperature it is raised, and at a much higher or only slightly higher temperature, it is lowered again to the working position. If it is set at a greater temperature difference, switching over will take place less frequently. The same system can also be used in a device such as that in Fig. 3 to turn these louvered packs of lamellae. This temperature control can be effectively used here to open the packs of lamellae to a greater or lesser extent, in which case the temperature control in normal wheather conditions controls at intermediate positions in which through turning through small angles more or less air can pass between two packs, thus without flowing along the lamellae. Here, the said temperature difference at which the controller operates can be selected to be so small that the angular position of the packs is even changed many times a day, thus not just reacting to considerable temperature differences between day and night, but also to smaller differences during the day, including differences in sunlight and clouding. In the device according to Figs. 1 and 2, this could also be used for more or less partial lifting, but this is slightly less practical. Of course, it is recommended that the said temperature difference should not be selected so small that the control causes a virtually continuous movement of the packs of lamellae.

[0017] Such an air cooler also moistens the air, and this is necessary or desirable for many applications in the cooling or condensation device connected downstream and is not a hindrance for many other applications. Of course, the system has to be designed and used in such a way that the humidity of the air does not exceed a desired value, i.e. in most cases in such a way that the air is not fully saturated, in order to prevent moisture condensing and precipitating at undesirable places. The invention can, however, also be used for cooling the air through a cooling agent not coming into contact with the air, which flows, for example, through pipes of the air cooler. All such considerations and possibilities are known as such.

Claims

1. A cooling or condensation device with air as the cooling medium, and with a cooler connected upstream thereof in the air flow for cooling said air, characterized in that said air cooler comprises one or more air cooling parts which are movably connected to a bearing structure of the device, in such a way that such parts can be moved fully or partially out of and into the path of the air stream to said cooling or condensation device.

2. Device according to claim 1, wherein the connecting means of said air cooler to said cooling or condensation device have a slide guide practically perpendicular to the path of said air stream, in such a way that said air cooler can be slid fully or partially out of said path.

3. Device according to claim 2, wherein said slide guide is designed for a practically vertical upward sliding of said air cooler.

4. Device according to claim 2 or claim 3, wherein provision is made for a box, into which the slide guide runs, and in which the air cooler is enclosed in its position outside the air path.

5. Device according to claim 1, wherein said air cooler is made up of parts which are each provided in their bearing structure so that they are rotatable about an axis extending approximately at right angles to said path of the air flow.

6. Device according to claim 5, wherein the movement mechanism for the air cooler parts is designed in such a way that adjacent air cooler parts are thereby turned in opposite directions.

7. Device according to any of the preceding claims, characterized in that the air cooler working with liquid is connected to a liquid discharge in such a way that when the cooler moves out of the path of the air stream, said discharge is opened automatically.

8. Device according to any of the preceding claims, characterized in that it has means for measurement of the temperature of the air used for cooling and signalling means to the movement means for the air cooler so that the air cooler is moved when a limit temperature is reached.

9. An air cooler for use in a device according to any of the preceding claims, with means to mount it in the air stream to a cooling or condensation device upstream of said device, in which device the air from the air cooler is used as the cooling medium.

Drawing