Air Cooling and Air Dehumidifying Module Comprising Capillary Tube Mats and Method of Using It
The invention relates to an air cooling and air dehumidifying module comprising plastic capillary tube mats, which are formed by folding and/or winding into a compact assembly with a virtually cuboidal outer shape, which cools and dehumidifies the air stream passed through the mat assembly when cold water is conducted through the capillary tubes. Furthermore, the invention relates to a method of operating the air cooling and air dehumidifying module in combination with cooling ceilings or suspended cooling panels. Such solutions serve for the decentralized cooling of rooms and for dehumidifying the air in a room.
The invention relates to an air cooling and air dehumidifying module with a heat exchanger element comprising plastic capillary tube mats which are shaped so as to form a compact packet with a virtually cuboid external shape, which cools and dehumidifies the air flow directed through the mat packet when cold water is fed through the capillary tubes. The invention further relates to a method of operating the air cooling and air dehumidifying module in combination with a cooling ceiling. The purpose of this type of solution is to cool a room and dehumidify the air in the room on a decentralised basis.
Compact water/air heat exchangers are generally made from metal, in which case aluminium and copper are used by preference due to their high capacity to conduct heat. These materials are expensive, require a lot of processing work and above all produce condensate in most applications, often leading to corrosion.
As a means of avoiding these disadvantages, it has been acknowledged that plastic capillary tube mats are very suitable as a means of providing a heat exchange surface. They are very versatile in terms of their use, for example for shaping making cooling and heating ceilings, suspended cooling panels, etc., which simultaneously form enclosure surfaces of a room. The heat exchange takes place by heat conduction, convection and radiation. These constructions cause a room to be cooled but they can and should not produce intensive air cooling as a result.
For the special application of cooling air by convection, one known approach (patent specification DE 198 06 207 C2) is to dispose capillary tube mats in a predominantly flat arrangement in a shaft so that the air circulation takes place between two vertically spaced apart openings due to the differences in density between the air in the shaft and that in the room. This also results in the concept of silent cooling. However, the heat exchanger will only operate at an appropriately high vertical shaft height, the air flow is relatively small and the efficiency is therefore limited.
In another known construction (DE 198 31 918 C2), similar to the one described above (in DE 198 06 207 C2), the top shaft opening communicates with the external air and the air quality in the room is improved by introducing conditioned external air.
Another known approach is to use plastic capillary tube mats for cooling and heating rooms and/or water baths (DE 197 51 883 C2), which, amongst other things, also contain a spiral-shaped, wound plastic capillary tube mat. Characteristic of this construction is a foil disposed between the capillary tube mats, which has projections (protuberances), by means of which passages are formed. As one flow of substance flows through the capillary tube mat, the second flow of substance is directed through the passages formed by the foil. From a hydraulic point of view, the high pressure loss which occurs due to the flow resistance on the foil is a particular disadvantage. From a thermodynamic point of view, the solution based on the spiral-shaped winding has various disadvantages. In certain regions, the foil lies against the capillary tubes, which means it is not possible to produce a free flow round them, thereby reducing the external coefficient of heat exchange. The result of an arrangement with a capillary mat with a single inlet for the liquid flow is a cross-counter flow guide system with a low proportion of counter-flow due to the fact that the secondary flow of substance is axially directed. If opting for several inlets, the pressure loss in the capillary tube mat rises sharply. The temperature of the externally directed flow of substance is not uniform across the cross-section of the heat exchanger, which can be a particular disadvantage at the outlet.
The disadvantages outlined above are avoided by the solution described in DPMA 103 13 384.4 (European patent application number 03016203.6), which is characterised by plastic capillary tube mats disposed in a spiral shape and with a radial air inlet. The disadvantage of this approach, however, is the large amount of space required due to the cylindrical heat exchange geometry, which means that it can be used for air-conditioning purposes in office and living spaces to a only limited degree.
In terms of practical applications, the known solutions outlined above are controlled on the basis of room temperature, which means that there is no active possibility of controlling the air humidity in the room.
The underlying objective of the invention is to satisfy the objectives for the air cooling and air humidifying module set out below:
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- a large surface should be achieved in the smallest possible space;
- in terms of its external dimensions, the heat exchanger element should be designed so that it can be integrated in devices and/or spaces available for construction—for example in ceiling cavities above cooling ceilings;
- the construction of the module and especially the heat exchanger element must lend itself well to maintenance and it must also be easy to replace the heat exchanger element;
- a material that is corrosion-proof and not susceptible to incrustration should be used for the heat exchanger surface;
- it should be possible to direct the flow in a thermodynamically conducive arrangement;
- it should be possible to achieve intensive air cooling and air dehumidification due to a high convective heat exchange at the surface of the heat exchanger element;
- it must be possible to control output according to room temperature or according to air humidity in the room;
- if the air cooling and air dehumidifying module is used in conjunction with a cooling ceiling or with other cooling surfaces in the room, it must be possible to control the temperature of the room actively and simultaneously also the air humidity of the room.
The set objectives are achieved by the invention on the basis of the characterising features defined in claims 1 and 26. A material corrosion-proof which is not susceptible to incrustation is used for the heat exchanger surface because plastic capillary tube mats are used. A good convective heat exchange is achieved at the heat exchanger surface through the transverse intake of the capillary tubes due to the short thermodynamic flow length achieved by the small diameter of the capillary tubes (as a rule smaller than 6 mm) and due to the circulation rate through the compact mat packet. This obviates the need for fin arrangements on the heat exchanger surfaces which are generally otherwise needed for heat exchangers, thereby providing an effective option for cleaning. A large surface is achieved in the smallest possible space due to the compact folding and/or winding technology so that the external geometry of the packet more or less assumes the shape of a cuboid. This fact offers ideal conditions for use in devices, in structurally restricted spaces, such as in ceiling cavities for example, and for replacing the heat exchanger element.
A permanent shape can also be imparted to the mat packet solely and/or additionally by making use of the memory effect—for example by a thermal pre-treatment.
One advantage in terms of the efficiency of this heating engineering is the fact that the air is directed through the mat packet in such a way that it primarily circulates in counter-flow with the water circulation.
It is of particular advantage from a construction and heating engineering point of view to use mat packets with a core region which is identical to the pressure chamber for distributing the air because this solution takes up a particularly small amount of space and a priori results in a thermodynamically conducive counter-flow.
Other advantageous features of the air cooling and air dehumidifying module are the arrangement of air distribution systems in the pressure chamber, the use of displaceable air inlet fittings in the pressure chamber and the design of the housing, which is conducive to introducing air into the room in a specific way depending on where the module is disposed in the room. For example, a source air passage can be formed by opting for a specific perforation pattern in the housing and using an air flow direction system, or a rectangular free jet can be generated by integrating air circulation elements of a slotted shape or alternatively an air flow with a higher turbulence can be created by means of a helical air passage.
It is also of advantage to combine the installations outlined above for taking in air, for distributing air or providing a passage for the air with systems for filtering the air.
The fact that the mat packet with its core region is fitted horizontally and the latter is used as a pressure chamber offers the option of an extremely flat construction, which lends itself particularly well to integration in ceiling cavities, e.g. above cooling ceilings or suspended cooling panels.
In one advantageous embodiment, a complete housing is dispensed with and if mat packets with a core region which can be used as a pressure chamber are employed, only blanking plates need be used for the core region, and at least one blanking plate is provided with an orifice for the incoming air.
Sealing bodies are built into the lateral ends of the mat packets in order to prevent or reduce bypass air flows, which conditions the air flow uniformly as it circulates.
In the case of larger pressure chambers or those with a geometrically pronounced, one-sided extension and/or for controlling the output of the module in stages, it is of advantage to install several fans and/or shaped pieces which help to direct and deflect the air.
The air flow distribution in the room to be air-conditioned can be further improved by encasing the mat packet in a foil with appropriate perforations or an appropriate fabric.
One special option for improving performance, i.e. for cooling air and dehumidifying air, is to use several mat packets disposed one after the other in the air flow in series, comprising folded and/or wound plastic capillary tube mats which are connected in counter-flow at the water end. To improve performance still further, several cold water inlets into the consecutive mat packets may also be provided.
In another embodiment, external air is directed partially or exclusively into the pressure chamber, as a result of which the external air flow which must necessarily be hygienic also undergoes a temperature and/or humidity change.
In order to improve conditions for users of the room from a heat and physiological point of view, it may be of advantage to treat specific room surfaces in a special way, for example to cool warm window or ceiling surfaces. To this end, the modules proposed by the invention are disposed so that an intensive air flow takes place along the pane, wall, etc., to be conditioned, if necessary using the Coandä effect.
Furthermore, the air cooling and air dehumidifying module may also be used during periods when it is necessary to heat the room by using hot water, in which case it assists or fully takes over the function of heating the room.
The output of the modules can be controlled by all known methods and combinations of them (varying the water inlet temperature, varying the water flow, varying the air flow volume, e.g. by speed control, shutting down individual fans, using gravitational force, etc.).
The method is also designed to increase efficiency from the point of view of primary energy use because, if the system is designed to operate at a low cold water temperature—which causes dehumidification due to condensation of the water vapour in the air as desired—and as high as possible a cold water temperature is used for the cooling ceiling, the room is cooled with a low exergic flow—for example due to a high proportion of ambient energy.
Special additional features are used which permit a practical and space-saving deployment of the air cooling and air dehumidifying module in conjunction with different types of cooling ceilings. In the case of open cooling ceilings and suspended cooling panels, the ambient air can expediently be drawn from directly underneath the room ceiling, i.e. via the cooling surface.
If the system proposed by the invention is to be fitted in large rooms or in individual rooms with a cooling load curve that is identical as a function of time, it is of practical advantage to form control zones for a group of air cooling and air dehumidifying modules in conjunction with the co-operating cooling ceilings and/or suspended cooling panels. Depending on the local extension of the control zones, it is of practical effect to determine the control variables comprising the room temperature and air humidity of the room on the basis of mean values obtained from several measurement values.
One advantageous solution for adapting output is to opt for a time control system, which is operated in anticipation of expected high load changes.
In order to save energy, it is of practical advantage to adapt the method so that an inactive range—a so-called energy zero band—lies between the switching stages of the control system, in which case the room is not cooled and the air is not dehumidified within fixedly defined threshold values or one of these activities is deliberately dispensed with.
Another option for simplifying automatic control is to regulate the room temperature only and operate dehumidification of the air on a passive basis so that the humidity of the room fluctuates freely within specific ranges based on a calculation of the humidity loads and the resultant dehumidification output calculated beforehand.
Of particular advantage in terms of economic use of energy resources is an automatic control system based on the objective of minimum exergic operation whilst producing optimum heat and physiological conditions in the room. This may be achieved by using a micro-computer, for example, which as a priority operates energy consumption based on water at a temperature as close to that of the room as possible and optimises the power distribution between the air cooling and air dehumidifying module and the cooling ceiling or suspended cooling panel.
It may also be of practical advantage to connect the water-end air cooling and air dehumidifying module and the cooling ceiling or suspended cooling panel in series because the cold water at low temperature causes dehumidification in the module and the higher return temperature out of the module serves as an intake for the cooling ceiling or suspended cooling panel. By carefully adapting the output, which is determined by the module size and the ceiling size, condensate can be prevented from forming on the cooling surfaces of the room.
The invention will be explained in more detail below with reference to examples of embodiments illustrated in the drawings.
Of these:
As illustrated in
As illustrated in
As illustrated in
By contrast with example 4,
Another special solution which can be of advantage in many applications is illustrated in
- 1 Dimensionally stable mat packet formed by layers
- 2 Dimensionally stable mat packet formed by parallel winding
- 3 Dimensionally stable mat packet formed by parallel winding with open core region
- 4 Width of the mat packet
- 5 Height of the mat packet
- 6 Core region of the mat packet
- 7 Capillary tube of the plastic capillary tube mat
- 8 Distributor or collection pipe (so-called cores) of the plastic capillary tube mat
- 9 Room, the air of which is supplied with cooled and dehumidified air
- 9a External air flow (atmosphere) for filling the pressure chamber
- 10 Air flow through the mat packet
- 11 Housing
- 12 Pressure chamber (air at a pressure higher than in 9)
- 13 Condensate catchment container
- 14 Cold water intake for the air cooling and air dehumidifying module
- 14a Cold water intake for the cooling ceiling or suspended cooling panel
- 15 Cold water return from the air cooling and air dehumidifying module
- 15a Cold water return from the cooling ceiling or suspended cooling panel
- 16 Cold water connecting line
- 17 Fan for conveying air into the pressure chamber 12 or the core region 6
- 18 Blanking plate of the mat packet
- 18a Blanking plate of the mat packet with air intake orifice
- 18b Blanking plate of the mat packet with air intake orifice and integrated fittings for directing the air with low pressure losses
- 19 Air flow from the room for filling the pressure chamber
- 19a External air flow (atmosphere) for filling the pressure chamber
- 20 Length of the mat packet
- 21 Sealing body to prevent leakage flows of non-conditioned air
- 22 Air cooling and air dehumidifying module
- 23 Cooled and dehumidified incoming air flow to the room
- 24 Closed cooling ceiling
- 24a Open cooling ceiling
- 25 Suspended cooling panel
- 25a Suspended cooling panel with passive function
- 26 Temperature sensor in the room
- 27 Humidity sensor in the room
- 28 Controller for the cooling output as a function of room temperature (thermostat)
- 29 Controller for the dehumidification output as a function of the room humidity (hygrostat)
- 30 Actuator system for influencing the volume of air flowing through the mat packet
Claims
1. An air cooling and air dehumidifying module for air-conditioning a room, the module comprising a plurality of plastic capillary tube mats, the capillary tube mats comprising distributor and collection tubes with flexible capillary tubes extending in between, through which water is circulated at a selectable temperature; wherein:
- the capillary tube mats are shaped to form a compact, dimensionally stable mat packet, the compact, dimensionally stable mat packet formed by layers of the tube mats; the compact, dimensionally stable mat packet formed by winding the tube mats without an enlarged interior; or the compact, dimensionally stable mat packet formed by winding the tube mats with a defined core region.
- so as to obtain a body resembling a cuboid,
- wherein one or more of the mat packets are disposed in a housing, the housing forming orifices so that a pressure chamber is created, to which a room air flow to be treated can be continuously fed by of one or more fans from the room to be air-conditioned into the pressure chamber, and
- wherein, a mat packet air flow occurs out of the pressure chamber and through the one or more mat packets due to the pressure difference prevailing between the pressure chamber and the room.
2. An air cooling and air dehumidifying module as claimed in claim 1,
- wherein one or more of the fans are connected on a side of the module adjacent to the pressure chamber, thereby creating a higher pressure in the pressure chamber than the air pressure in the room thereby causing air circulation through the one or more mat packets.
3. An air cooling and air dehumidifying module as claimed in claim 1,
- wherein the height of the cuboid body is at least twice the width of the cuboid body.
4. An air cooling and air dehumidifying module as claimed in claim 2, wherein
- the height of the cuboid body is at least twice the width of the cuboid body, and
- a plurality of sealing bodies attached to the mat packets seal the pressure chamber in order to prevent bypass flows of non-conditioned air.
5. An air cooling and air dehumidifying module as claimed in claim 4,
- wherein the orifices formed from the housing are slots, holes or perforations.
6. An air cooling and air dehumidifying module as claimed in claim 5,
- wherein each capillary tube comprises a capillary tube surface, wherein the mat packet air flow contacts the tube surface thereby causing a convective heat exchange and at a low water temperature in the capillary tube mats the air is also dried due to a formation of condensation water caused by a drop below the dew point at the capillary tube surface.
7. An air cooling and air dehumidifying module as claimed in claim 6,
- wherein each mat packet comprises (i) plastic binders or (ii) a thermal pre-treatment mat packet that provides permanent dimensional stability to the mat packet.
8. An air cooling and air dehumidifying module as claimed in any of claims 1-7,
- wherein a plurality of mat packets are connected in series or in parallel in the same mat packet air flow to improve the efficiency of the module, and the water flow is directed in counter-flow by providing a cold water inlet, a cold water connecting pipe, and a cold water outlet.
9. An air cooling and air dehumidifying module as claimed in claim 1,
- wherein the compact, dimensionally stable mat packet formed by winding the tube mats with a defined core region is positioned in the housing so that the defined core region of the compact, dimensionally stable mat packet assumes the function of the pressure chamber and is filled with room air by one or more fans, and the mat packet air flow is distributed to several sides in the room and contacts the capillary tube surface so that a counter-flow is achieved with the water inlet and the water outlet.
10. An air cooling and air dehumidifying module as claimed in of claim 1,
- wherein the pressure chamber has integrated fittings for distributing the air thereby ensuring an air discharge into the room that is uniform or selectively directed depending on usage conditions.
11. An air cooling and air dehumidifying module as claimed in any of claims 1 to 5, further comprising a plug-in flange and/or roller fans with rotatable housings so that air intake of the room air can be flexibly designed depending on the disposition of the module in the room.
12. An air cooling and air dehumidifying module as claimed in claim 1, wherein the housing is shaped to form air passage elements on the surfaces of the housing or the air passage elements are connected to the housing, the air passage elements comprising perforated plate arrangements, slotted passages or adjustable slat plates.
13. An air cooling and air dehumidifying module as claimed in claim 1, wherein the mat packets with a defined core region can be fitted horizontally.
14. An air cooling and air dehumidifying module for air-conditioning a room, the module comprising a plurality of plastic capillary tube mats, the capillary tube mats comprising distributor and collection tubes with flexible capillary tubes extending in between, through which water is circulated at a selectable temperature; wherein, the capillary tube mats are shaped to form a compact, dimensionally stable mat packet, the compact, dimensionally stable mat packet formed by winding the tube mats with a defined core region, so as claimed in to obtain a body resembling a cuboid, and
- wherein the defined core region of the compact, dimensionally stable mat packet is closed by means of a closed blanking plate and by a blanking plate with an air intake orifice lying opposite.
15. An air cooling and air dehumidifying module for air system comprising a module as claimed in claim 1, and a plurality of fans disposed to fill the pressure chamber with room air flow.
16. A system as claimed in claim 15, wherein shaped pieces are fitted between one or more of the fans and the pressure chamber in order to direct and deflect the mat packet air flow.
17. An air cooling and air dehumidifying module as claimed in claim 1, wherein the mat packet is enclosed by a perforated foil, the perforations of which constitute the air passage orifices.
18. An air cooling and air dehumidifying module as claimed in claim 1, wherein during the operation of the module a constant, automatically controllable or controllable external air flow is fed to the pressure chamber.
19. An air cooling and air dehumidifying module as claimed in claim 1, wherein the module is disposed in a room comprising windows or passive suspended cooling panels whereby the air circulates so that air is blown onto the surfaces of the windows or passive suspended cooling panels so that the surface temperature of the windows or passive suspended cooling panels is reduced.
20. An air cooling and air dehumidifying module disposed as claimed in claim 19, wherein the surface temperature of the windows or passive suspended cooling panels is reduced by the Coandä effect.
21. An air cooling and air dehumidifying module disposed as claimed in claim 1, further comprising one or more air filters and/or air humidifiers integrated in the air path through the air cooling and air dehumidifying module.
22. An air cooling and air dehumidifying module disposed as claimed in claim 1, wherein power regulation of the air cooling and air dehumidifying module takes place on the basis of a variable water temperature, a variable water flow and/or a variable flow volume of air through the mat packet.
23. An air cooling and air dehumidifying module disposed as claimed in claim 1, wherein one or more of the fans are connected on a side of the module adjacent to a suction end of pressure chamber, thereby creating lower pressure in the pressure chamber than the air pressure in the room, thereby causing air circulation through the mat packet.
24. An air cooling and air dehumidifying module as claimed in claim 1, wherein the one or more mat packets are disposed in the housing so that the air circulation through the one or more mat packets is caused by density differences between the cooled air and the room air at reduced power.
25. An air cooling and air dehumidifying module as claimed in claim 1, wherein the module is also able to assume a heating function by using water temperatures above the room air temperature.
26. A method for air-conditioning a room, the method comprising
- providing a control unit comprising an air cooling and air dehumidifying module as claimed in claim 1, irrespective of a spatial location of the module, and a cooling ceiling, irrespective of a construction type of the ceiling;
- controlling the power of the air cooling and air dehumidifying module so that the desired value of the room air humidity is preserved and
- controlling the power of the cooling ceiling to achieve the desired room temperature.
27. A method according to claim 26, further comprising
- supplying the air cooling and air dehumidifying module and the cooling ceiling with cold water flows comprising varying initial temperatures in order to gain the advantage of a low exergy during operation, and
- circulating a lower temperature water flow through the air cooling and dehumidifying module.
28. A method according to claim 26, further comprising
- providing the cooling ceiling, wherein the cooling ceiling is an open cooling ceiling or a suspended cooling panel, and
- drawing room air from the ceiling gap by means of the air cooling and dehumidifying module.
29. A method according to claims 26, further comprising
- connecting structurally the air cooling and dehumidifying module and the cooling ceiling or a suspended cooling panel to one another, and/or
- forming a structural unit from the air cooling and dehumidifying module and the cooling ceiling or a suspended cooling panel.
30. A method according to claim 26, further comprising
- controlling the room temperature and/or the room air humidity for a defined room zone or for a group of rooms.
31. A method according to claim 26, further comprising
- deriving control variables comprising room temperature and room air humidity which are arithmetic or weighted mean values, from the signals of a plurality of measuring sensors.
32. A method according to claim 26, further comprising
- adapting the power of the air cooling and dehumidifying module and/or the cooling ceiling and/or a suspended cooling panel is on the basis of a time control system.
33. A method according to claim 26, further comprising
- operating the air cooling and dehumidifying module and/or the cooling ceiling and/or a suspended cooling panel as a function of predefined temperature and/or humidity threshold values which are exceeded or below which there is a drop.
34. A method according to claim 26, further comprising
- operating the air cooling and dehumidifying module and/or the cooling ceiling and/or a suspended cooling panel based on the premise of maintaining the room temperature, and
- controlling the power of the air cooling and dehumidifying module and/or the cooling ceiling and/or a suspended cooling panel based on the premise of maintaining the room temperature.
35. A method according to claim 26, further comprising
- regulating or controlling automatically the dehumidifying power of the air cooling and dehumidifying module as a function of a signal of one or more humidity sensors and/or temperature sensors which are installed in conjunction with the cooling ceiling and/or a suspended cooling panel so that condensation is prevented on the cooling ceiling.
36. A method according to claim 26, further comprising
- operating the air cooling and dehumidifying module and/or the cooling ceiling and/or a suspended cooling panel as a function of a target function of achieving minimum exergy at optimum room air conditioning and/or thermal comfort, and
- regulating the power of the air cooling and dehumidifying module and/or the cooling ceiling and/or a suspended cooling panel as a function of the target function of achieving minimum exergy at optimum room air conditioning and/or thermal comfort.
37. A method according to claims 26, further comprising
- connecting the cooling ceiling and/or a suspended cooling panel downstream of the air cooling and dehumidifying module at a water end, and
- corresponding a cold water return from the air cooling and dehumidifying module to a cold water intake for the cooling ceiling or for the suspended cooling panel.
38. A method according to claims 26, further comprising
- operating the air cooling and dehumidifying module in combination with other room cooling surfaces, an output of which can be automatically regulated and/or controlled, for example flat room dividers or wall surfaces, in addition to or instead of cooling ceilings.
Type: Application
Filed: Jul 28, 2005
Publication Date: Sep 18, 2008
Applicant: Clina Heiz-und Kulelemente GmbH (Berlin)
Inventor: Bechir Chahed (Berlin)
Application Number: 11/996,739
International Classification: F24F 3/14 (20060101);