DE10253264B4 - Decentralized air conditioning system, to heat/cool a room space, takes in a primary external air flow to be combined with a secondary air flow from the room space, to pass together through a heat exchanger - Google Patents

Abstract

The decentralized air conditioning system, for heating/cooling a space, has a primary air supply unit and especially from external air (10). All the primary air is combined with a secondary air flow (12) which is wholly or partially air taken from the conditioned room space (16). All or part of the combined air flow (13) passes through a heat exchanger (3) to raise or lower its temperature to be delivered into the space. The primary/external air in the combined air flow is set to deliver fresh air at a rate of at least 40 m3/hour per person or at least 5 m3/hour per m2 of the surface area. The temperature of the combined air flow is at least 0 deg. C before it enters the heat exchanger.

Description

The The invention relates to a decentralized ventilation device, in particular for heating or cooling a room.

On the one hand, there is a fresh air rate per hour and person of around 40 m ³ / h or of approximately 5 m ³ / h per square meter of usable space from standards for recreation rooms. On the other hand, for office space cooling power is required to compensate for heat loads, for example, by people present (about 100 W (watt) per person), appliances (PCs, fax, copier, lighting, etc.) and sunlight, and then rising room temperatures above 26 ° C to prevent. On the one hand, therefore, the supply of fresh air is required, on the other hand, apply cooling power. Since fresh air introduced into the room from the outside into the room is normally warmer or colder or more humid or dry than room air, the fresh air must be conditioned in complex processes, which often leads to the fact that, for reasons of cost, only the minimum fresh air volume flow required is the space is supplied. Normally, the aforementioned cooling capacity can not be dissipated with said mandatory volume flow of fresh air, that is, it is not possible to cool the fresh air so strong that it compensates for the heat load in the room, without causing condensation phenomena that avoid the formation of moisture nests are to be avoided. The extremely strong cooling is not useful for comfort reasons (thermal comfort).

Known Training variants for the fresh air supply is the climate control center that has at least the minimum amount of fresh air central processing and over extensive sewer networks to the rooms respectively. Furthermore, decentralized devices known. These are devices associated with the particular room that on the facade, in the balustrade, can be arranged on the ground or on the ceiling, to the shortest way the Fresh air, preferably the minimum amount of fresh air, in the room blow. As fresh air here is the ambient air (outside air) used. After all is for the fresh air intake the natural one ventilation to mention, that means it be - if possible - window open in the room. Known variations for applying the cooling power are central air conditioning, who needed the cooling capacity centrally and, for example, one above the minimum fresh air flow outgoing air volume flow respectively. In such a case, the sewer system must be dimensioned correspondingly larger be. Furthermore, decentralized devices are known for applying the cooling power. These may be cold water-fed convection refrigerators, which promote the circulating air by means of a fan. Furthermore, cooling ceilings known by radiation cooling greater surfaces a room cooling cause. By means of so-called induction devices, primary air is transmitted induction nozzles directed to drive a circulating air flow by induction, the one heat exchanger happens.

at a known, decentralized direct cooling or heating system is outside air in the needed Minimum amount of fresh air sucked in and through a heat exchanger directed. This results in a direct cooling or direct heating the air that is blown into the room. In winter is through a frost guard ensure that, for example, -14 ° C cold outside air does not freeze of water in the heat exchanger leads. In summer, for example, 32 ° C name is and humid outside air be cooled without condensation only to the dew point of about 20 ° C.

From the EP 0 756 139 A2 is a mixed air conveyor known, which simultaneously conveys outside air and indoor air and sucks through a heat exchanger.

The DE 21 48 047 A relates to a device in which a fan promotes secondary air through an inlet. The secondary air sweeps along a primary air inlet and can entrain primary air.

The EP 1 162 411 A1 relates to a central device in which primary air flows into a Luftverteilkasten via a pipeline network and then passes through nozzles to a heat exchanger.

Of the Invention is based on the object, a decentralized ventilation technology Device to provide, with, despite low fresh air flow rate, preferably the standard minimum fresh air volume flow, a pleasant room climate is created. This is done without condensation phenomena both in the case of cooling, in the heating case and possibly also in the case of pure ventilation.

This object is achieved by a decentralized ventilation device according to the features of claim 1. By the measure according to the invention, by means of a primary air / outside air flow through primary air conveyor, especially outside air conveyor, the subsidized primary air or outside air or a portion thereof with a secondary air flow, in particular a room air flow, or a proportion thereof merge, in particular to Mi rule, and the merged air flow then supply all or at least a portion thereof at least one heat exchanger and then bring the treated by the heat exchanger air flow in the room, is avoided by the mixture of outdoor and indoor air, especially in the winter before the heat exchanger prevail air temperatures that could cause a freeze , In particular, the combined air stream upstream of the heat exchanger already has a temperature above 0 ° C, since the cold outside air is heated by the admixing of warm room air. Compared to the above-mentioned decentralized direct cooling or direct heating system therefore larger volume flows can be driven through the heat exchanger. With thermally improved facades of buildings and decreasing k-values of the glazing of these buildings, the cooling case in winter is becoming more and more important. For example, in a 3-axis office, a cold load of 600 W may occur on clear days despite outside temperatures of minus 14 ° C. In this case, the decentralized air conditioners, for example, have a free cooling capacity of 1,440 W, if, for example, 120 m ³ / h of fresh air are pumped into the room. By reheating the outside air, the outlet temperature will be adjusted so that the required cooling capacity is provided. Now the question arises about the blow-out temperatures of different device concepts. A comparison shows the following table:

In The table is the value of a decentralized, known system without induction effect with and without heat recovery (WRG) the decentralized system with direct induction (inventive design), again, no heat recovery or a central heat recovery is provided. In the central heat recovery this takes place in the central exhaust air with heat pump.

It can be seen from the table that with a conventional decentralized device without induction, a blow-out temperature of 7.0 ° C would be set at the required cooling capacity. In a device according to the invention with direct induction, that is, according to the principle of the invention, the outlet temperature is 14.5 ° C by admixing room air. For reasons of comfort, it can be provided that by means of a Reg the outlet temperature is limited to, for example, 16 ° C. For a device that conveys outside air directly through the heat exchanger, the outside air would then need to be reheated to 1200 W to achieve 240 W of cooling in the room. In a device according to the invention with direct induction, the reheating is only 960 W (that is 20% less), with a cooling capacity of 480 W (100 increase) is achieved in space.

Become both systems with heat recovery operated (conventional Systems with a decentralized heat exchanger / direct induction devices according to the invention with central Exhaust air heat recovery and heat pump), then it turns out that the required reheating and thus the Heating energy may be lowered. The usable free cooling can with limitation of the discharge temperature by a heat recovery not increased become. If exhaust temperature and room temperature are fixed, then you can only over an increase the volume flow more free cooling be used. If the outlet temperature is not limited, then For direct induction, there is always greater thermal comfort for the user because the exhaust temperature due to the process closer to the Room temperature is lower than in conventional systems.

According to a further development, it is provided that the primary air fraction / fresh air fraction of the combined air flow corresponds to the required minimum amount of fresh air for compliance with the air requirements in the room (fresh air at least per person 40m ³ / h or 5m ³ / h per m ² usable area of the room).

Preferably will - like already mentioned - the device designed such that the proportions of primary air / outside air and secondary air / room air of the merged Air flow selected such be that the temperature of the combined air flow upstream of the heat exchanger is above 0 ° C.

It is advantageous if the decentralized ventilation device as a decentralized single device, in particular decentralized air conditioner, trained and preferably as overground, Underfloor or ceiling installation device is trained. In the case of an overfloor device can also training as a parapet device, in particular as integrated in the facade device may be provided.

To a development of the invention is the decentralized single device in the area the facade of the room. This is a short way the introduction of outside air possible. In particular, it can be provided that a single room with several decentralized individual devices Is provided.

To a development of the invention, it is provided that the secondary air flow / room air flow or a portion of which flows through another heat exchanger before he promoted to the Primary air / outside air or the proportion of subsidized Primary air / outside air meets. The secondary air / room air thus becomes first through the other heat exchanger conditioned and only then meets with the primary air / outside air to the mixed air to form, which is then the first heat exchanger, So not the other, second heat exchanger, flows through. It is but also possible that only a single heat exchanger is present, so that the further heat exchanger covers an area of this heat exchanger forms and another area of the heat exchanger for the mixed air to disposal stands.

Especially can be provided that the promotion the room air / secondary air by means of the primary air / outside air Induced induction occurs. Alternatively, it can also be provided that promotion the room air / secondary air by means of a turbomachine, in particular a fan is performed. For the primary air / outside air is always a conveyor, for example, a turbomachine, in particular a fan, provided. It is also advantageous if the promotion of primary air / outside air and secondary air / room air with the same turbomachine, in particular the same fan.

A Another advantageous embodiment is characterized by a in particular infinitely adjustable air adjusting device upstream of the flow machine is arranged and the primary air / outside air as well as secondary air / room air be supplied as each adjustable in volume flow input variables. ever after adjustment or adjustment of the air adjustment device the mixed air is composed of a corresponding percentage of primary air / outside air as well as secondary air / room air together, in extreme cases 0 percent primary air / outside air and 100 percent secondary air / room air in the other extreme case 100 percent primary air / outside air as well as 0 percent secondary air / room air. All Intermediate sizes are preferably continuously adjustable.

It is also advantageous if the merging of conveyed primary air / outside air and secondary air / room air takes place immediately before the heat exchanger, ie in a zone immediately before the active Part of the heat exchanger.

The The invention further relates to a method for decentralized heating or Cool a room, with a primary air extraction, in particular outside air promotion, wherein at least a portion of the funded or the total funded primary air / outside air with a secondary air flow, in particular room air stream, or a proportion thereof preferably, below Induced induction combined and then the merged Air flow in total or part thereof by means of a heat exchanger warmth- or cold-treated is poured into the room after this treatment.

The Invention is based on embodiments explained in more detail, and though shows:

1 a schematic longitudinal sectional view through a decentralized ventilation device for heating or cooling a room,

2 a further embodiment of a device according to 1 .

3 a further embodiment of a device according to 1 .

4 a schematic view of the structure of a decentralized ventilation device,

5 a Auslegeungsvariante the construction of the 4 .

6 a variant of the construction of the 4 .

7 one of the 4 corresponding embodiment of a decentralized ventilation device, but with additional heat exchanger for the room air and

8th a schematic view of a room equipped with ventilation equipment room of a building or the like.

The 1 shows - in a schematic representation - a decentralized ventilation device 1 that a housing 2 having. In the case 2 is a heat exchanger 3 and an induction device 4 arranged. The heat exchanger 3 is in an inclined position within the housing 2 positioned so that it faces the wall 5 of the housing 2 an exit space 6 and to the wall 7 of the housing 2 a mixed room 8th results. The induction device 4 points to the heat exchanger 3 to form a passage opening 9 a distance up.

below the terms "outside air" and "room air" are used. These make concretizations of the generic term "primary air" for the term "outside air" and "secondary air" for the term "indoor air". If therefore from "outside air" or "indoor air" is the speech, should This always also the more general term "Pri märluft" or "secondary air" are understood.

In operation, the induction device 4 outside air 10 by means of a in the 1 supplied turbomachine, not shown. The outside air 10 placed in an air distribution box 11 of the housing 2 flows, passes through not shown induction nozzles in the mixing chamber 8th and generates there due to the nozzle action an induction effect, which leads to that through the passage opening 9 room air 12 from a room 16 is sucked. In the mixing room 8th be outside air 10 and room air 12 merged. The merged airflow 13 , the mixed air 14 forms, passes through the heat exchanger 3 and is - depending on the cooling water - or heating water temperature of the heat exchanger 3 - Cooled (summer operation) or heated (winter operation) and enters the exit space 6 as supply air 15 in the room 16 a building or the like occurs. Of importance is that - seen in the flow direction - in front of the heat exchanger 3 , in particular immediately in front of the heat exchanger 3 , bringing together outside air 10 and room air 12 by induction effect, wherein high induction ratios (secondary air to primary air or outside air to room air) can be generated, which are in the range of 0 to 6. This means that a part of outside air, for example, sucks in 5 parts of room air by induction, so that a total of 6 parts flow through the heat exchanger and into space 16 escape.

To illustrate the air currents, the device is the 1 again within a room 16 according to 8th shown. The device 1 is in the 8th in the area of the facade 17 of the room 16 arranged, with the facade 17 a window 18 having. Below the window 18 is the decentralized ventilation system 1 , which is designed as a parapet device. The air distribution box 11 is about a wall breakthrough 19 in the facade 17 in contact with the outside air. An air conveyor system, not shown, sucks outside air and leads it to the induction nozzles of the induction device 4 to. In the mixing room 8th becomes room air due to the induction effect 12 sucked in front of the heat exchanger 3 with the outside air 10 is mixed. The mixed air passes through the heat exchanger 3 and arrives according to arrow 20 in the room 16 ,

The 2 shows a further embodiment of a decentralized ventilation device 1 that sucking in room air 12 from two sides. For this purpose, the housing 2 between the walls 5 and 7 a horizontally installed heat exchanger 3 on. The induction device 4 is arranged centrally under the heat exchanger, with its air distribution box 11 both to the wall 5 as well as to the wall 7 in each case one passage opening 9 leaves. Now kick outside air 10 by corresponding, not shown primary air nozzles in the mixing chamber 8th - Seen in terms of flow - before the heat exchanger 3 is, a, is so by induction effect from both sides, so through both passages 9 room air 12 sucked and enters the mixing room 8th , The mixed air thus formed 14 passes through the heat exchanger 3 and enters the top as supply air 15 in the room 16 one.

The 3 shows a further embodiment of a decentralized ventilation device 1 which is essentially the embodiment of the 1 corresponds, so that only the differences should be discussed here. These are the wall 5 of the housing 2 not down to the bottom of the heat exchanger 3 ranges, but the active zone of the heat exchanger 3 so interspersed that the wall 5 with a section 21 into the area of the mixing room 8th enough. Also exists between the heat exchanger 3 and the air distribution box 11 no passage opening 9 but the two components end up together so that there is no room air between them 12 can occur. The heat exchanger 3 is due to the special leadership of the wall 5 in two areas 22 and 23 divided, the area 22 almost the function of the heat exchanger 3 according to 1 takes over and the area 23 forms a "further heat exchanger", which - as will be explained below - the treatment of the room air 12 serves, before this to the mixing room 8th arrives.

In operation of the device 1 according to 3 becomes the induction device 4 outside air 10 by means of a turbomachine, not shown, for example, a fan supplied. The outside air 10 enters the mixing chamber through not shown primary air nozzles 8th and there creates an induction effect, which leads to air in the room 12 out of the room 16 is sucked in and the area 23 of the heat exchanger 3 flows through. Here, the room air 12 - depending on the operating mode of the area 23 of the heat exchanger 3 or operating mode of the entire heat exchanger 3 - Are thermally preconditioned, that is either heated or cooled. The pretreated room air 12 passes through the induction effect in the mixing chamber 8th and meets the outside air there 10 , It comes to the formation of mixed air 14 that the wider area 22 - in the opposite direction as the room air 12 in the area 23 - the heat exchanger 3 flows through and into the exit space 6 arrives. When passing through the mixed air 14 through the area 22 of the heat exchanger 3 is the mixed air - according to the operating mode of said area 22 or the entire heat exchanger 3 - Conditionally conditioned, that is, cooled or heated. The treated air enters as supply air 15 in the room 16 ,

The 4 illustrates a decentralized ventilation system 1 using a block diagram. outside air 10 is by means of a turbomachine 24 , in particular a fan 25 , sucked, and a muffler 26 fed. The silencer 26 leaving outside air hits the induction device 4 and passes through the induction nozzles (not shown) in the mixing chamber 8th , From the side flows into the mixing room 8th room air 12 , The outside air 10 and room air 12 formed mixed air 14 passes through the heat exchanger 3 and enters as supply air 15 in the room 16 ,

The block diagram of the 5 illustrates a construction variant of a decentralized ventilation system 1 in which the turbomachine 25 not only outside air 10 but also indoor air 12 sucks. The room air 12 intersperses a silencer 27 , The from the turbomachine 24 promoted, from outside air 10 and room air 12 composed conveying air / mixed air reaches the silencer 26 and from there to the heat exchanger 3 , The the heat exchanger 3 leaving air (supply air 15 ) enters the room 16 ,

The embodiment of 6 corresponds to the embodiment of 5 , The only difference is that upstream of the turbomachine 24 an air-adjusting device 28 is arranged, the two inputs 29 . 30 and an exit 31 has. Preferably, the air adjustment device 28 a continuously adjustable damper 32 on. Depending on the position of the valve 32 becomes the entrance 30 opened and in the same way the entrance 29 locked. In this way it is possible that through the two inputs 29 and 30 together 100 percent air enters, the mixing ratio being through the two inputs 29 and 30 entering air is influenced by the flap position. So it is possible, for example, that the entrance 29 20 percent of the air enters with the consequence that the entrance 30 80% of the air lying on it. The result is that - depending on the setting of the air adjustment device 28 - the ratio of room air 12 and outside air 10 can be adjusted because the entrance 29 room air 12 over a silencer 27 is fed and at the entrance 30 outside air 10 pending. The corresponding, from the air conditioning device 28 provided air mixture exits the exit 31 the air conditioning device 28 out and will - looked at by the turbomachine 24 - over the muffler 26 the heat exchanger 3 and from there as supply air 15 the room 16 fed.

The 7 shows an embodiment that the design of the embodiment of 4 equivalent. Reference is therefore made to the accompanying description. The only difference is that another heat exchanger 3 ' is provided by the room air 12 is enforced. The room air is thus by means of the heat exchanger 3 ' pretreated and only then reaches the mixing room 8th , Comparing the embodiment of 7 with the representation of 3 so is the heat exchanger 3 the area 22 and the heat exchanger 3 ' the area 23 correspondingly effective. While in the 3 an integrated design is present, the heat exchangers 3 and 3 ' in 7 separate building units.

In all embodiments, it is crucial that the mixed air, which is composed of primary air and secondary air or from outside air and room air in front of the heat exchanger 3 merged and then as mixed air together the heat exchanger 3 interspersed.

At the The subject matter of the invention uses outside air with the precisely required minimum fresh air volume flow, to carry out a standard-compliant operation. As already mentioned, can the promotion the secondary air / room air either by means of a turbomachine be done or be induced due to the induction principle, this means, primary Air induces the secondary Air according to the jet pump principle. The heat exchanger points at all embodiments The invention preferably has a low pressure drop to one possible high secondary Volume flow to allow. By the invention, the risk of freezing of the heat exchanger in cold outside air in winter depending the outside air temperature avoided, that is, on additional Protection measures like Frostguard, can mostly be dispensed with altogether. The protection features that the according to the invention, decentralized air conditioning for a building and the facade of the building takes over, have an extraordinary high priority. A central theme takes the mentioned danger of freezing of the heat exchanger one. In case of a malfunction, for example, a failure of the heat exchangers supplying warm water pump must be closed in winter "the facade", that is, the Outside air intake must be partially or completely prevented, otherwise the heat exchanger destroyed by freezing would become. Below the air inlet temperature below 0 ° C at one Place the heat exchanger enough then already out to destroy it within a few minutes. Therefore it is usually not sufficient, a single, selective acting temperature sensor to use. Preferably, a capillary tube sensor is used, which is arranged or bent is that it covers the entire heat exchanger surface, the pointing in the direction of the outside air, covered or recorded its temperature. In the procedure according to the invention The direct induction only occurs at an outside temperature of for example -14 ° C an inlet temperature from 0 ° C in the heat exchanger one. Because of the resulting procedural safety of 14 K (Kelvin) against freezing, the antifreeze can be controlled the discharge temperature can be significantly simplified. By the arrangement according to the invention can be at the same primary Air or gas flow and the same Kühlmittelvorlauf- or Heizmittelvorlauftemperatur in the room a higher cooling or heating capacity be achieved, as in an arrangement in which exclusively the primary Air or gas stream cooled or heated becomes. Furthermore, the inventive arrangement in the cooling case, the Setting a colder Coolant temperature possible, without the condensate, that means it's always a higher one condensate-free cooling capacity possible as in a direct blowing through the heat exchanger.

at the direct induction according to the invention will be a significant increase in performance achieved in that the funded by the heat exchanger volume flow increased by induction becomes. This is the outside air first mixed with the room air and then the mixed air through the heat exchanger promoted.

By Admixture of room air to outside air before entering the heat exchanger The formation of condensate can be greatly reduced or completely avoided become. A rapid increase in outside air humidity, for example through a thunderstorm, leads in the outside air to a rapid increase in the dew point temperature and in known, directly flowing through heat exchangers for condensate separation. Is by the direct induction according to the invention the "dry" room air of the outside air admixed, the dew point at the heat exchanger inlet is timed greatly delayed achieved, leaving enough time for the regulation of the device is the flow temperature in the room or in the building raise and thus effectively avoid condensation. Next the mixture of indoor and outdoor air come in the invention also memory effects to fruition, in addition to lead, that the room humidity rises more slowly than the mixture calculation expect. Cheap geometric relationships of the heat exchanger (For example, a depth of only about 40 to 50 mm) and the so associated short residence time of the air at the heat exchanger fin support this effect in addition.

Claims (16)

Decentralized ventilation system ( 1 ), in particular for heating or cooling a room, with a primary air / primary air flow through only primary air conveyor, in particular outside air conveyor, wherein at least a proportion of subsidized or the total funded primary air / outside air with a secondary air flow, in particular room air flow, or a proportion thereof is merged and then the combined air stream as a whole or a part thereof at least one heat exchanger ( 3 ), in particular for heating or cooling purposes, flows through and then enters the room. Device according to claim 1, characterized in that the primary air portion / outside air portion of the combined air flow to the required minimum fresh air volume flow to maintain the air requirements in the room corresponds (fresh air at least per person 40 m ³ / h or at least 5 m ³ / h per m ² Effective area of the room). Device according to one of the preceding claims, characterized characterized in that the proportions of primary air / outside air and secondary air / room air of the merged Air flow selected such be that the temperature of the combined air flow upstream of the heat exchanger is above 0 ° C. Device according to one of the preceding claims, characterized characterized in that the decentralized ventilation device as decentralized single device, in particular air conditioner, trained and preferably designed as above-floor, underfloor or ceiling installation device. Device according to one of the preceding claims, characterized characterized in that the decentralized single unit in the area of the facade of Room is set up. Device according to one of the preceding claims, characterized characterized in that several decentralized individual devices in the room are arranged. Device according to one of the preceding claims, characterized characterized in that the secondary air flow / room air flow or a portion of which flows through another heat exchanger before he promoted to the Primary air / outside air or the proportion of subsidized Primary air / outside air meets. Device according to one of the preceding claims, characterized characterized in that the heat exchanger and the other heat exchanger Areas of a common heat exchanger form. Device according to one of the preceding claims, characterized characterized in that the promotion of Secondary air / air by means of the primary air / outside air Induced induction occurs. Device according to one of the preceding claims, characterized characterized in that the promotion of Secondary air / air by means of a turbomachine, especially fan, takes place. Device according to one of the preceding claims, characterized characterized in that the promotion of Primary air / outside air by means of a turbomachine, especially fan, takes place. Device according to one of the preceding claims, characterized characterized in that the promotion of Primary air / outside air and secondary air / room air with the same turbomachine, especially fan, takes place. Device according to one of the preceding claims, characterized by a particularly stepless adjustable air adjustment device, the upstream the turbomachine is arranged and the primary air / outside air as well as secondary air / room air be supplied as each adjustable in volume flow input variables. Device according to one of the preceding claims, characterized characterized in that the merger of subsidized Primary air / outside air and secondary air / room air immediately before the heat exchanger he follows. Device according to one of the preceding claims, characterized by training as a parapet, in particular as in the facade of a building or room integrated device. Method for decentralized heating or cooling of a Room, with only one primary air / outside air promoting Primary air promotion, in particular outside air extraction, being a share of the subsidized or the entire subsidized Primary air / outside air with a secondary air flow, in particular room air flow, or a proportion thereof is brought together and subsequently the merged Air flow in total or part thereof by means of at least one heat exchanger temperature-treated, in particular heated for heating purposes or for cooling purposes chilled and that the treated air stream is subsequently introduced into the room becomes.