JP2005024115A - Adsorption type refrigerating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the efficiency and capacity of an adsorption type refrigerating machine by lowering heat exchange loss. <P>SOLUTION: This adsorption type refrigerating machine is constituted such that an adsorbent in an adsorbing step is directly cooled by the outside air. By this, since the heat exchange loss when the adsorbent is cooled can be reduced less than a case in which the adsorbent is cooled indirectly through a liquid cooled by the outside air, the adsorbent can be securely cooled and the efficiency and capacity of the adsorption type refrigerating machine can be increased. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an adsorption refrigeration machine that uses a function of adsorbing a gas-phase refrigerant to evaporate the refrigerant and exerts a refrigerating capacity by the latent heat of vaporization. For example, an electronic device in a mobile phone base station It is effective for cooling electric devices, electric converters, batteries and the like.
[0002]
[Prior art]
In the conventional mobile phone base station cooling system, heat is absorbed from the first heating element, and the second heating element is cooled by an adsorption refrigerator that operates by the absorbed heat (see, for example, Patent Document 1).
[0003]
[Patent Document 1]
JP 2002-100951 A
[Problems to be solved by the invention]
However, in the invention described in Patent Document 1, the adsorbent and the vapor refrigerant desorbed and released from the adsorbent are cooled via the liquid such as water cooled in the outdoor air by the outdoor heat exchanger. It may be difficult to sufficiently cool the adsorbent and the vapor refrigerant desorbed and released from the adsorbent due to heat exchange loss when heat is exchanged between the outside air and the liquid.
[0005]
In the invention described in Patent Document 1, the adsorbent is heated through the liquid heated by absorbing heat from the first heating element 2, and the refrigerant adsorbed on the adsorbent is desorbed and released. 1 It may be difficult to sufficiently heat the adsorbent due to heat exchange loss when heat is exchanged between the heating element and the liquid.
[0006]
Further, in the invention described in Patent Document 1, the liquid is cooled by the cold heat generated in the adsorption refrigerator, and the second heating element is cooled through the cooled liquid. Therefore, heat exchange when cooling the liquid is performed. Due to the loss, it may be difficult to sufficiently cool the second heating element.
[0007]
Furthermore, since heat is exchanged via the liquid, if a liquid leak occurs at the connection part of the liquid pipe for some reason, the electronic device, the electric device, the electric converter in the mobile phone base station Otherwise, the battery or the like may be damaged.
[0008]
In view of the above points, the present invention firstly provides a novel adsorption refrigerator that is different from the conventional one, and secondly, reduces the heat exchange loss and improves the efficiency and capacity of the adsorption refrigerator. For the purpose.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, in the invention according to claim 1, the refrigerant is evaporated by utilizing the action of the adsorbent adsorbing the gas-phase refrigerant, and the refrigerating capacity is exhibited by the latent heat of vaporization. A first heat exchanger (6) for heating or cooling the adsorbent, and a first gas supply means for supplying a heating gas or a cooling gas to the first heat exchanger (6) (8).
[0010]
This makes it possible to reduce the heat exchange loss when cooling or heating the adsorbent as compared with the invention described in Patent Document 1 that indirectly cools or heats the liquid, so that the adsorbent can be reliably used. It can be cooled or heated.
[0011]
In the invention according to claim 2, the adsorbent and the refrigerant are enclosed in the sealed container (5), and the refrigerant that is not adsorbed by the adsorbent among the refrigerants present in the sealed container (5) is heated or It has the 2nd heat exchanger (7) which cools, and the 2nd gas supply means (9, 10) which supplies the gas for heating or the gas for cooling to the 2nd heat exchanger (7), It is characterized by the above-mentioned.
[0012]
Thereby, compared with the invention of patent document 1 which cools or heats indirectly via a liquid, since the heat exchange loss at the time of cooling or heating the refrigerant | coolant which is not adsorbed by adsorption agent can be made small. The refrigerant that is not adsorbed by the adsorbent can be reliably cooled or heated.
[0013]
The invention described in claim 3 is characterized in that air is used as the heating gas and the cooling gas.
[0014]
The invention according to claim 4 includes an evaporating heat exchanger (12) for evaporating the refrigerant, and a condensing heat exchanger (13) for cooling and condensing the gas phase refrigerant desorbed and released from the adsorbent, The gas supplied to the evaporation heat exchanger (12) and the condensation heat exchanger (13) is at least one of carbon dioxide, nitrogen monoxide, dinitrogen monoxide, methane, acetylene, ethylene, ethane, propylene, and propane. One gas is used.
[0015]
Thereby, heat transport capability can be improved compared with air, for example.
[0016]
Moreover, since it is sufficient to always supply the same kind of gas to the condensation heat exchanger (13) and the evaporation heat exchanger (12), it is not necessary to provide a valve for switching the gas flow. The manufacturing cost of the machine can be reduced.
[0017]
Incidentally, the reference numerals in parentheses of each means described above are an example showing the correspondence with the specific means described in the embodiments described later.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
In the present embodiment, the adsorption refrigeration machine according to the present invention is applied to cooling an electronic device or an electric device in a mobile phone base station, and FIG. 1 is a schematic diagram of a cooling system according to the present embodiment. FIG. 2 is a graph showing the moisture adsorption rate of the adsorbent, and FIG. 3 is a four-sided view of the refrigerator 4.
[0019]
The rack 1 in the mobile phone base station has a relatively large amount of heat generation, and a first heating element comprising a radio wave transmission amplifier, radio wave output control panel, rectifier, electronic device, electrical device, electrical converter, etc. 2, a second heating element 3 composed of a circuit control panel, a battery, an electronic device, an electric device, an electric converter, a modem, and the like that need to be cooled at a lower temperature than the first heating element 2, and both the heating elements 2, 3 A refrigerator 4 for cooling is provided.
[0020]
In addition, both the heat generating elements 2 and 3 are not operated independently, but both the elements 2 and 3 operate in conjunction with each other, and the first heat generating element 2 has a higher heat resistance temperature than the second heat generating element 3. The first heating element 2 and the second heating element 3 are forcibly air-cooled by blowing air inside the mobile phone base station, that is, inside air.
[0021]
The refrigerator 4 is an adsorption refrigerator that operates by absorbing heat from the first heating element 2 and heating the adsorbent with the absorbed heat. Hereinafter, the adsorption refrigerator (refrigerator 4) will be described. .
[0022]
The adsorbent adsorbs the refrigerant (in this embodiment, water) and desorbs the adsorbed refrigerant by being heated. In this embodiment, the adsorbent is a solid adsorbent such as silica gel or zeolite. Is adopted.
[0023]
That is, the moisture (refrigerant) adsorption rate of the adsorbent is determined by a value obtained by dividing the saturated water vapor pressure of the refrigerant temperature by the saturated water vapor pressure corresponding to the adsorbent temperature (hereinafter referred to as relative humidity), as shown in FIG. Furthermore, the relative humidity decreases as the adsorbent temperature increases and the refrigerant temperature decreases, and conversely, the relative humidity increases as the adsorbent temperature decreases and the refrigerant temperature increases.
[0024]
In FIG. 2, the adsorption process, that is, the moisture adsorption characteristic when moisture adsorption proceeds, and the desorption process, that is, the moisture adsorption characteristic when moisture desorption proceeds, are drawn to be the same. The actual adsorbent has a hysteresis such that the water adsorption characteristic during the adsorption process and the water adsorption characteristic during the desorption process are different.
[0025]
Further, in FIG. 1, the adsorber 5 is a hermetically sealed vacuum container in which a refrigerant is sealed in a state where the inside is maintained in a substantially vacuum, and in the adsorber 5, a first heat exchange is performed between the adsorbent and air. Among the refrigerants enclosed in the heat exchanger 6 and the adsorber 5, the refrigerant that is not adsorbed by the adsorbent, that is, the liquid phase refrigerant (water) and the gas phase refrigerant (water vapor) desorbed and released from the adsorbent and air. And a second heat exchanger 7 that exchanges heat with each other.
[0026]
The first heat exchanger 6 has an adsorbent adhering to an outer surface of a core portion made of a plurality of tubes through which air flows and a fin or the like provided on the outer surface of the tubes to increase a heat transfer area with an epoxy resin or the like. It forms an adsorbing core.
[0027]
The second heat exchanger 7 is also an evaporation / condensation core comprising a plurality of tubes through which air flows as in the first heat exchanger 6, and fins provided on the outer surface of the tubes to increase the heat transfer area. In this embodiment, the first heat exchanger 6 is positioned above the second heat exchanger 7.
[0028]
The refrigerator 4 according to the present embodiment includes a plurality of adsorbers 5a and 5b. The adsorber 5a (hereinafter referred to as the first adsorber 5a) disposed on the upper side of FIG. 3B. 3) and the adsorber 5b (hereinafter referred to as the second adsorber 5b) arranged on the lower side in FIG. 3B have the same configuration, and therefore when the two are collectively referred to, the adsorber 5 Is written.
[0029]
Further, the subscript a of the heat exchangers 6 and 7 indicates that the heat exchanger is in the first adsorber 5a, and b indicates that the heat exchanger is in the second adsorber 5b.
[0030]
In FIG. 1, the outside air fan 8 is a blower that introduces air outside the mobile phone base station (outside air) into the air piping for the refrigerator 4, and the cooling fan 9 uses the air cooled by the second heat exchanger 7. It is a blower that blows air to the second heating element 3, and the heating fan 10 cools the first heating element 2, collects waste heat of the first heating element 2, and sends the air whose temperature has risen to the first heat exchanger 6. It is a blower that blows air.
[0031]
In FIG. 3, valves 11a to 11h are plate door type switching valves for switching the air flow through the air piping, and the operations of these valves 11a to 11h and fans 8 to 10 are controlled by an electronic control device (not shown). ing.
[0032]
Next, a schematic operation of the cooling system according to the present embodiment, that is, the refrigerator 4 will be described.
[0033]
The refrigerator 4 continuously cools the first heating element 2 and the second heating element 3 by switching and operating the first and second basic operation modes described below every predetermined time.
[0034]
Incidentally, the predetermined time is appropriately selected based on the time necessary for desorbing the refrigerant adsorbed by the adsorbent.
[0035]
1. First basic operation mode In this mode, the cooling air blown to the second heating element 3 is blown to the second heat exchanger 7b of the second adsorber 5b, thereby evaporating the liquid-phase refrigerant in the second adsorber 5b. Then, the cooling air is cooled to cool the second heating element 3, and the vapor-phase refrigerant evaporated in the second adsorber 5b, that is, water vapor is adsorbed by the adsorbent in the second adsorber 5b.
[0036]
At this time, the adsorbent generates a heat amount corresponding to the heat of condensation, and the adsorbing capacity decreases as the temperature of the adsorbent rises. The adsorbent is cooled by supplying the first heat exchanger 6b.
[0037]
On the other hand, the air heated by the first heating element 2 by the heating fan 10 is supplied to the first heat exchanger 6a of the first adsorber 5a to heat the adsorbent, and the refrigerant adsorbed on the adsorbent. Is desorbed and released, and air outside the mobile phone base station is supplied to the second heat exchanger 7a of the first adsorber 5a, and the desorbed gas-phase refrigerant (water vapor) is cooled and condensed.
[0038]
Hereinafter, the adsorber 5 in a state where the vapor phase refrigerant evaporated is adsorbed by the adsorbent while evaporating the liquid phase refrigerant and exhibiting the refrigerating capacity is referred to as the “adsorber 5 in the adsorption process”. The adsorber 5 in a state where the adsorbent is heated to desorb the adsorbed refrigerant and the desorbed refrigerant is cooled and condensed is referred to as “the adsorber 5 in the desorption process”. "
[0039]
2. Second Basic Operation Mode In this mode, contrary to the first basic operation mode, the first adsorber 5a is used as an adsorption process, and the second adsorber 5b is used as a desorption process.
[0040]
Specifically, the cooling air blown to the second heating element 3 is blown to the second heat exchanger 7a of the first adsorber 5a, thereby evaporating the liquid refrigerant in the first adsorber 5a and cooling air. The second heating element 3 is cooled to cool the vapor-phase refrigerant evaporated in the first adsorber 5a, that is, water vapor by the adsorbent in the first adsorber 5a, while the outside air fan 8 The adsorbent is cooled by supplying air outside the mobile phone base station to the first heat exchanger 6a of the first adsorber 5a.
[0041]
On the other hand, the air heated by the first heating element 2 by the heating fan 10 is supplied to the second heat exchanger 6b of the second adsorber 5b to heat the adsorbent, and the refrigerant adsorbed on the adsorbent. Is desorbed and released, and air outside the mobile phone base station is supplied to the second heat exchanger 7b of the second adsorber 5b, so that the desorbed gas-phase refrigerant (water vapor) is cooled and condensed.
[0042]
Next, the function and effect of this embodiment will be described.
[0043]
In the present embodiment, the adsorbent in the adsorption process is directly cooled by the outside air, whereas in the invention described in Patent Document 1, the adsorbent is indirectly cooled by the liquid cooled by the outside air. Therefore, in this embodiment, the heat exchange loss at the time of cooling an adsorbent can be made small compared with the invention of patent document 1, and an adsorbent can be cooled reliably.
[0044]
That is, when the heat transfer coefficient when exchanging heat with air is α1, and the heat transfer coefficient when exchanging heat with the liquid is α2, the cooling capacity of the adsorbent in the cooling system according to the present embodiment is On the other hand, the cooling capacity of the adsorbent in the cooling system described in Patent Document 1 increases in proportion to the product of the temperature difference ΔT1 between the outside air and the heat transfer coefficient α1, and the heat difference between the temperature difference ΔT2 between the outside air and the liquid. It increases in proportion to the product of the rate α1 and the heat transfer rate α2.
[0045]
At this time, in general, the heat transfer coefficient α1 and the heat transfer coefficient α2 are both smaller than 1, and since the heat transfer coefficient α2 is smaller than 1, the temperature difference ΔT2 is smaller than the temperature difference ΔT1. The cooling capacity of the adsorbent in the described cooling system is smaller than the cooling capacity of the adsorbent in the cooling system according to this embodiment.
[0046]
Further, in the present embodiment, the adsorbent in the desorption step is directly heated by the air heated by the first heating element 2, whereas in the invention described in Patent Document 1, Since it is heated indirectly via the liquid heated by the 1 heating element 2, in this embodiment, heat exchange loss at the time of heating an adsorbent is made small compared with the invention of patent documents 1. And the adsorbent can be reliably heated.
[0047]
Further, when the second heating element 3 is cooled by the refrigerator 4, in the present embodiment, the second heating element 3 is directly cooled by the air cooled by the second heat exchanger 7. In the invention described in Patent Document 1, the second heating element is indirectly coupled with the liquid cooled by the second heat exchanger 7 by air to cool the second heating element 3 with air. 3 is cooled, the heat exchange loss at the time of cooling the 2nd heat generating body 3 can be made small compared with the invention of patent document 1, and the 2nd heat generating body 3 can be cooled reliably.
[0048]
In addition, since heat is exchanged via air, even if an air leak occurs at the connection part of the air piping due to some reason, electronic devices, electric devices, electric converters, There is no problem of damaging the battery or the like.
[0049]
In this embodiment, since the adsorbent or the like is directly heated or cooled with a gas such as air without using a liquid, the number of heat exchangers is reduced compared to the invention described in Patent Document 1. The manufacturing cost of the refrigerator 4, that is, the cooling system can be reduced.
[0050]
(Second Embodiment)
In the first embodiment, the second heat exchanger 7 heats the refrigerant, that is, cools the air sent to the second heating element 3 and cools the gas phase refrigerant desorbed and released from the adsorbent. In this embodiment, as shown in FIGS. 4 and 5, an evaporation heat exchanger 12 that absorbs heat from the air blown to the second heating element 3 and evaporates the refrigerant, and a vapor phase desorbed and released from the adsorbent. A condensation heat exchanger 13 for cooling and condensing the refrigerant is provided, the condensation heat exchanger 13 is disposed above the first heat exchanger 6 in the adsorber 5, and the evaporation heat exchanger 12. Are disposed below the first heat exchanger 6, the space 14 a in which the condensation heat exchanger 13 is disposed, the spaces 14 b and 14 c in which the first heat exchanger 6 is disposed, and the evaporation heat exchanger 12. 14d is separated from the space 14d and each open / close valve 15a to 15d And controls the communication state between 14a to 14d.
[0051]
The space 14a and the space 14d are always in communication via the return pipe 16, and the space 14b is a space in which the first heat exchanger 6a of the first adsorber 5a is disposed, and the space 14c is the first space 14c. This is a space in which the first heat exchanger 6b of the two adsorber 5b is arranged.
[0052]
In this embodiment, the open / close valves 15a to 15d are plate door types, and both the valves 15a and 15b are controlled by the electronic control device together with the valves 11a to 11d and the like.
[0053]
Next, the general operation of the refrigerator 4 according to this embodiment will be described.
[0054]
The refrigerator 4 according to the present embodiment also continuously cools the first heating element 2 and the second heating element 3 by switching the first and second basic operation modes described below every predetermined time. is there.
[0055]
1. First Basic Operation Mode In this mode, the space 14d in which the evaporation heat exchanger 12 is arranged, that is, the evaporation chamber and the space 14c in which the first heat exchanger 6b is arranged communicate with each other, and the first heat exchanger 6a The cooling air blown to the second heating element 3 is blown to the evaporating heat exchanger 12b in a state where the space 14b in which the heat exchanger 13 is arranged communicates with the space 14a in which the heat exchanger 13 for condensation is placed, that is, the condensing chamber. As a result, the liquid-phase refrigerant in the evaporation chamber 14d is evaporated to cool the cooling air.
[0056]
In addition, the gas-phase refrigerant evaporated in the evaporation chamber 14d is supplied to the first heat exchanger 6b by supplying air outside the mobile phone base station to the first heat exchanger 6b and the adsorbent filled in the first heat exchanger 6b is cooled. It is adsorbed by the adsorbent filled in the heat exchanger 6b.
[0057]
On the other hand, by supplying the air heated by the first heating element 2 to the first heat exchanger 6a, the adsorbent is heated to desorb and release the refrigerant adsorbed on the adsorbent, and the heat for condensation. Air outside the mobile phone base station is supplied to the exchanger 13 to cool and condense the gas-phase refrigerant flowing into the condensation chamber 14a. Note that the liquid-phase refrigerant in the condensing chamber 14 a is supplied to the evaporation chamber 14 d via the return pipe 16.
[0058]
2. Second basic operation mode In contrast to the first basic operation mode, this mode uses the adsorbent filled in the first heat exchanger 6a as an adsorption step, and removes the adsorbent filled in the first heat exchanger 6b. It is a separation process.
[0059]
Specifically, the second heat generation is performed in a state where the evaporation chamber 14d and the space 14b in which the first heat exchanger 6a is disposed communicate with each other, and the first heat exchanger 6b space 14c and the condensation chamber 14a communicate with each other. By sending the cooling air blown to the body 3 to the evaporating heat exchanger 12b, the liquid refrigerant in the evaporation chamber 14d is evaporated to cool the cooling air.
[0060]
Further, the gas-phase refrigerant evaporated in the evaporation chamber 14d is supplied to the first heat exchanger 6a by cooling the adsorbent filled in the first heat exchanger 6a by supplying air outside the mobile phone base station to the first heat exchanger 6a. Adsorption is performed with an adsorbent filled in the heat exchanger 6a.
[0061]
On the other hand, by supplying air heated by the first heating element 2 to the first heat exchanger 6b, the adsorbent is heated to desorb and release the refrigerant adsorbed on the adsorbent, and the heat for condensation. Air outside the mobile phone base station is supplied to the exchanger 13 to cool and condense the gas-phase refrigerant flowing into the condensation chamber 14a.
[0062]
Next, the function and effect of this embodiment will be described.
[0063]
In the present embodiment, the condensation heat exchanger 13 is exclusively used for condensation. Therefore, it is sufficient to always supply cold air, that is, outside air, to the condensation heat exchanger 13. The valve for switching can be abolished.
[0064]
Similarly, since the evaporating heat exchanger 12 is dedicated to evaporating, it is sufficient to always supply the air that has cooled the second heating element 3 to the evaporating heat exchanger 12, so a valve for switching the air flow is provided. Can be abolished.
[0065]
(Third embodiment)
In the second embodiment, the air outside the mobile phone base station is supplied only to the condensation heat exchanger 13 and the first heat exchanger 6, and only the air inside the mobile phone base station circulates in the evaporating heat exchanger 12. Therefore, in the present embodiment, the entire mobile phone base station is a highly airtight sealed space, and carbon dioxide, nitric oxide, dinitrogen monoxide, methane, acetylene, ethylene, ethane, propylene are contained in the mobile phone base station. The cooling fan 9 and the heating fan 10 are reduced in power consumption by enclosing a gas having a high heat transport capability such as propane.
[0066]
(Other embodiments)
In the above-described embodiment, the present invention has been described by taking the mobile phone base station as an example. However, the present invention is not limited to this, and it is in a space such as a building, basement, factory, warehouse, house, garage, and vehicle. The present invention can be applied to cooling a plurality of types of heating elements (for example, a gas turbine engine, a gas engine, a diesel engine, a gasoline engine, a fuel cell, an electronic device, an electric device, an electric converter, and a storage battery).
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a cooling system according to a first embodiment of the present invention.
FIG. 2 is a graph showing the moisture adsorption rate of the adsorbent.
3A is a schematic front view of the refrigerator according to the first embodiment of the present invention, FIG. 3B is a top view of FIG. 3A, and FIG. 3C is a bottom view of FIG. (D) is a right side view of (a).
FIG. 4 is a schematic diagram of a cooling system according to a second embodiment of the present invention.
5A is a schematic front view of a refrigerator according to a second embodiment of the present invention, FIG. 5B is a left side view of FIG. 5A, and FIG. 5C is a right side view of FIG. (D) is a top view of (a).
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Rack, 2 ... 1st heat generating body, 3 ... 2nd heat generating body, 4 ... Adsorption type refrigerator,
5 ... Adsorber, 6 ... First heat exchanger (adsorption core),
7 ... second heat exchanger (evaporation / condensation core), 8 ... outside air fan,
9 ... Cooling fan, 10 ... Heating fan.

Claims (4)

An adsorption refrigeration machine that uses the action of the adsorbent to adsorb the gas-phase refrigerant, evaporates the refrigerant, and exhibits refrigeration capacity by its latent heat of vaporization,
A first heat exchanger (6) for heating or cooling the adsorbent;
An adsorption refrigeration apparatus comprising first gas supply means (8) for supplying a heating gas or a cooling gas to the first heat exchanger (6). The adsorbent and the refrigerant are enclosed in a sealed container (5),
A second heat exchanger (7) for heating or cooling a refrigerant that is not adsorbed by the adsorbent among the refrigerants present in the sealed container (5);
The adsorption refrigeration apparatus according to claim 1, further comprising second gas supply means (9, 10) for supplying a heating gas or a cooling gas to the second heat exchanger (7). The adsorption refrigerator according to claim 1 or 2, wherein air is used as the heating gas and the cooling gas. An evaporating heat exchanger (12) for evaporating the refrigerant;
A condensation heat exchanger (13) for cooling and condensing the gas-phase refrigerant desorbed and released from the adsorbent,
As gas supplied to the heat exchanger for evaporation (12) and the heat exchanger for condensation (13), carbon dioxide, nitrogen monoxide, dinitrogen monoxide, methane, acetylene, ethylene, ethane, propylene, and propane are used. The adsorption refrigerator according to claim 1, wherein at least one gas is used.

Images