JP2686474B2 - Absorption refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption refrigerating machine, and more particularly to an absorption refrigerating machine for improving the heat exchange efficiency of a portion requiring heat exchange.

[0002]

2. Description of the Related Art A corrugated bellows fin obtained by processing a heat exchanger of an absorption refrigerator by continuously bending a thin plate, and a seal plate for sealing an end face of a chamber formed by peaks and valleys of the bellows fin. The present applicant has filed Japanese Patent Application No. 3-52559 and Japanese Patent Application No. 3-1697.
No.57 has been proposed. In such cases, the refrigerant during heat exchange,
In order for the solution to adhere well to the plate surface (heat transfer surface) of the bellows fin, the plate surface is knurled to form irregularities. In order to knurl the surface of the plate, the thickness of the plate is, for example, 1.0 mm to 1.5.
There is a problem in that it needs to be large, such as in mm, requires a large amount of material, causes a large loss, and requires time and effort for knurling.

Therefore, the present applicant sought a means for obtaining a heat exchange efficiency equal to or higher than the fear without being restricted by the knurled surface of the plate surface, and proposed, as an example thereof, Japanese Patent Application No. 4-7602. There is. Practical application 4-7602
In the example of No. 6, as shown in FIG. 4, at least one of an evaporator, an absorber, a condenser, and a low-temperature regenerator of an absorption refrigerator is processed by continuously bending thin plates into a corrugated bellows fin. 1 and a heat exchanger composed of seal plates 2 and 3 for sealing the chambers 5 and 8 formed by the peaks and valleys of the bellows fin 1 at the end faces, and the refrigerant in the chambers 5 and 8 It is characterized in that the net 9 is inserted in a chamber through which the like passes. According to this configuration, the refrigerant and / or the solution supplied to the chambers 5, 8 and the like are supplied to the chambers 5, 5 via the net 9.
8 and the like wet and spread on the plate surface and adhere to that portion during heat exchange, and the effect of improving heat transfer efficiency is obtained.

[0004]

Japanese Patent Application No. 4-7602 discloses a structure in which the flow of a cooling medium or the like is suppressed by a net 9 inserted in the chambers 5 and 8, and the wetting and spreading of the cooling medium or the like on the plate surface. , Adhesion is taken into consideration. In addition, if the discharge of the product such as the refrigerant vapor after the heat exchange and the promotion of the supply of the refrigerant on the plate surface are improved, the heat exchange efficiency can be further improved. The conventional technique does not consider the simultaneous realization of both and the improvement of heat exchange efficiency therewith, and there is room for improvement in this respect.

An object of the present invention is to solve the above problems and improve heat exchange efficiency in an absorption refrigerator.

[0006]

In order to achieve the above-mentioned object, a refrigerant or the like is made difficult to flow near the surface of the heat transfer plate and diffused in the lateral direction, and is made easy to flow at the center of the flow path, and is made close to the surface of the plate. It came to the knowledge that it would suffice if the refrigerant and the like could flow laterally with respect to the center. For example, the net 9 of Japanese Patent Application No. 4-7602 was improved to form a porous layer in which layers with different meshes were superposed. We have come to the conclusion that the above method is effective.

Based on this, the above-mentioned problems are solved by a high temperature regenerator for heating a dilute solution with a heating source, a separator for separating the solution heated by the high temperature regenerator into a refrigerant vapor and an intermediate concentrated solution, and the separator. A high temperature solution heat exchanger for exchanging the intermediate concentrated solution with a dilute solution, and the intermediate concentrated solution whose temperature has been lowered by the high temperature solution heat exchanger is reheated by the refrigerant vapor coming from the separator to obtain an intermediate concentrated solution. A low temperature regenerator that further generates a refrigerant vapor to form a concentrated solution, a condenser that liquefies and liquefies the refrigerant vapor generated in the low temperature regenerator into a refrigerant liquid, and sprays the refrigerant liquid from the condenser to the cooler. An evaporator that obtains cold water from a cooler, and an absorber that absorbs the refrigerant vapor vaporized in the evaporator by spraying a concentrated solution that performs heat exchange from the low temperature regenerator through a low temperature solution heat exchanger. , Heat exchange the dilute solution that has absorbed the refrigerant in the absorber And a solution circulation pump for sending it to the high temperature regenerator through a reactor, and at least one of the evaporator, the absorber, the condenser, and the low temperature regenerator is processed by continuous bending of a thin plate to form a corrugated shape. In an absorption refrigerator comprising a heat exchanger composed of a bellows fin and a seal plate which seals a chamber formed by a peak portion and a valley portion of the bellows fin at an end surface, a refrigerant and / or Alternatively, it is achieved by an absorption refrigerator, in which a porous layer having higher permeability inside than both outer sides is inserted into a chamber through which the solution passes.

As an example for carrying out the above structure, the porous layer has a structure in which a pair of woven wire mesh and an expanded metal inside thereof are overlapped. Desirably, the pair of woven wire meshes are brought into close contact with the surface of the heat transfer plate by brazing or the like.

In the absorption refrigerator having the above-mentioned structure, the heat exchanger having the above-mentioned characteristics is formed in at least one of an evaporator, an absorber and a low temperature regenerator.

When the evaporator is constituted by the heat exchanger, one of the chambers formed by the bellows fin peaks and valleys is closed in the absorption refrigerating machine, and cold water (or hot water) is drawn from below in the vertical direction. ) Is introduced and discharged from above, the refrigerant liquid is dropped from above the bellows fin into the other chamber, and the expanded metal is also inserted into the chamber into which the cold water (or hot water) is introduced. Is desirable.

When the absorber is constituted by the heat exchanger, one of the chambers formed by the bellows fin peaks and troughs is closed in the absorption refrigerator, and cooling water is introduced from below in the vertical direction. And allow the refrigerant vapor to pass while dripping the concentrated solution from above the bellows fin to the other chamber, and also inserting the expanded metal into the chamber for introducing the cooling water. Is desirable.

[0012]

According to the above-mentioned structure, portions requiring heat exchange, for example, cold water (circulating water) and refrigerant water flowing in the evaporator are corrugated bellows fins formed by continuous bending of thin plates and peaks of the bellows fins. Flow in the chamber formed by the groove and the valley in the opposite directions, the contact area dramatically increases, and since the porous layer is inserted in the chamber through which the coolant flows, the coolant flows in the lateral direction. The heat transfer efficiency between the cold water and the refrigerant liquid is improved by improving the wettability and spreadability of the water. Similarly, since a porous layer was inserted in the chamber through which the absorbing solution passed, even in the case of an absorber or a low temperature regenerator, the wetting and spreading property of the solution in the lateral direction was improved to improve heat transfer efficiency and absorption performance or boiling heat transfer property. Become.

Further, in the porous layer having the above structure, the permeability of the porous layer is low near the plate surface of the bellows fin, so that the fluid such as the refrigerant is hard to flow. On the other hand, since the porous layer has high permeability at the center of the flow path of the refrigerant or the like, the refrigerant vapor or the like easily flows. The lateral flow of the solution etc. is free,
Therefore, products such as refrigerant vapor generated by heat exchange flow through the center of the flow path and are discharged to the outside,
Along with the flow, the flow is disturbed by the porous layer, and the refrigerant and the solution are agitated. In this way, wetting and spreading properties of the refrigerant,
Stirrability, dischargeability, and refrigerant, without impairing adhesion
The supply of the solution is enhanced, and the heat exchange efficiency is further improved.

[0014]

An embodiment of the present invention will be described below with reference to the drawings. Prior to describing the heat exchanger of the absorption refrigerator, an outline of a general absorption refrigerator will be described with reference to FIG. In FIG. 3, a high-temperature regenerator 21 has a combustion chamber housed therein, heats a dilute solution having a reduced concentration by absorbing a refrigerant, and generates refrigerant vapor from the dilute solution.
The separator 22 separates the refrigerant vapor from the intermediate concentrated solution having a high concentration by evaporating the refrigerant vapor, and sends the former to the high-temperature solution heat exchanger 27 and the latter to the low-temperature regenerator 23. Condenser 24
Is the refrigerant vapor generated in the low temperature regenerator 23 and the low temperature regenerator 23.
Refrigerant vapor that has not become the refrigerant liquid is cooled and liquefied by using cooling water to be a refrigerant liquid and sent to the evaporator 25. Evaporator 25
Is a heat transfer tube (cooler) through which circulating water to be cooled flows.
5A is arranged, the refrigerant liquid sent from the condenser 24 to the heat transfer tube 25A is sprayed using the sprayer 25B, and the circulating water is cooled by using the heat of vaporization when the refrigerant liquid becomes the refrigerant vapor. And make it cold water.

In the absorber 26, the concentrated solution which has passed through the low temperature solution heat exchanger 28 from the low temperature regenerator 23 is introduced and sprayed and dropped by using the sprayer 26B provided at the upper part, and the concentrated solution is evaporated 25 Absorbs the vaporized refrigerant inside. A high vacuum is secured in the evaporator 25 by the absorption function of the absorber 26, and the refrigerant liquid sprayed on the heat transfer tube 25A in the evaporator 25 can be immediately evaporated. Also,
The absorber 26 is provided with cooling means 26A for cooling when the concentrated solution absorbs the refrigerant vapor and becomes a diluted solution.
The cooling means 26A is composed of a coil, and the condenser 2
4 is also connected to the cooling means 24A, and cooling water circulates inside.

The high temperature solution heat exchanger 27 exchanges heat between the high temperature intermediate concentrated solution and the low temperature diluted solution, and the low temperature solution heat exchanger 28 exchanges between the high temperature concentrated solution and the low temperature diluted solution. Heat is exchanged and two stages are provided on the high temperature side and the low temperature side to improve the heat exchange efficiency. The solution circulation pump 29 sends the dilute solution that has absorbed the refrigerant vapor in the absorber 26 to the high-temperature regenerator 21 via the low-temperature solution heat exchanger 28 and the high-temperature solution heat exchanger 27, and circulates the solution again. Is provided. Reference numeral 30 is a cooling / heating switching valve, and this cooling / heating switching valve 30 includes the separator 22, the evaporator 25, and the absorber 2.
6 is provided in the middle of the pipe, and at the time of heating, the high temperature refrigerant vapor generated in the high temperature regenerator 21 is directly introduced into the evaporator 25 via the separator 22 and is circulated in the heat transfer pipe (water heater) 25A. It exchanges heat with to obtain hot water.

The heat exchanger of the present invention is used in, for example, the evaporator 25, the absorber 26, the low temperature regenerator 23 and the like of the absorption refrigerator shown in FIG. 3, and its embodiment is shown in FIG. Shown in. The same members as those described above are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, an inlet 6 is formed in the lower part of one closed chamber 5 formed by the bellows fin 1 and the side plate 4.
An exit 7 is provided at the top. A mesh 9A is inserted into the other chamber 8 so that a liquid refrigerant or a solution is dripped into the chamber 8 from a sprayer 10 arranged above the heat exchanger. In this embodiment, the porous layer is a net body 9A in which three net materials are superposed.
A is formed by inserting an expanded metal 9C in a sandwich shape between a pair of woven wire nets 9B on both outer sides. The expanded metal 9C has a mesh size larger than that of the woven wire mesh 9B, and both outer sides of the reticulated body 9A are larger than the inner side.
Refrigerant, solution, etc. are difficult to flow.

The woven wire net 9B may be any of a plain woven wire net, a twill woven wire net, and a tatami woven wire net, but is preferably JIS G.
The size specified in 3555 is preferable. Further, the expanded metal 9C preferably has a size defined by JIS G 3351, and the mesh size is 12 × 30.5 mm to ensure an effective gap, although it depends on the height of the peaks and valleys of the bellows fin 1. It is desirable to set it within the range of 25 × 60 mm. The mesh size of the woven wire net 9B will be described later.

It is preferable to join both outer sides of the woven wire net 9B to both side plates of the chamber 8 by brazing or the like so that the refrigerant or solution adhering to the net 9A flows to the heat transfer surface side and diffuses. It's even better if you do it.

As shown in Japanese Patent Application No. 4-7602, room 8
Even if only the expanded metal 9C having a small mesh size is inserted, a predetermined wetting and spreading action can be obtained. on the other hand,
If the products such as the evaporated refrigerant vapor are not quickly discharged from the heat transfer surface after the heat exchange, the refrigerant and the solution are difficult to be supplied to the plate of the chamber 8, and the reaction efficiency during the heat exchange may be reduced. Therefore, in order to facilitate discharging, it is also necessary to make the expanded metal 9 have a large mesh size and a large opening area. As described above, since the mesh sizes of the expanded metal that meet the two requirements are contradictory to each other, it is considered that the spreading and wetting and the promotion of the supply of the refrigerant and the solution cannot be easily realized at the same time.

On the other hand, in this embodiment, it has been found that the both can be realized at the same time by improving the net structure inserted into the room. Specifically, in this embodiment, the reticulate body 9 is used.
A is inserted as a sandwich structure of expanded metal 9C by a woven wire mesh 9B. In that configuration,
When the refrigerant and the solution are supplied, the mesh size is small on the side of the woven wire mesh 9B, so that the refrigerant and the solution do not easily flow, and the woven wire mesh 9
It spreads to B and has good wet spreadability. On the other hand, on the expanded metal 9C side, since the mesh size is large, products generated by heat exchange, particularly gases such as refrigerant vapor, easily flow, and flow and discharge quickly. further,
As the gas flows, the flow is disturbed by the expanded metal 9C and the like, and the refrigerant and the solution are stirred. Accordingly, the supply of the next refrigerant and solution is promoted, and the reaction efficiency of heat exchange is improved.

Thus, the coolant on the plate surface,
The wettability and spreadability of the solution are improved, the supply of the refrigerant and the solution is promoted, and the heat exchange efficiency can be further improved. As shown in Japanese Patent Application No. 4-7602, by inserting the mesh body 9A into the chamber 8 through which the refrigerant and the solution are separated by the folding plate, the flow path due to thermal strain during brazing in the furnace is formed. It is also possible to prevent the heat exchange efficiency from decreasing due to the reduction of the heat insulating area. The operation of this heat exchanger when used in the evaporator 25, the absorber 26, the low temperature regenerator 23, etc. will be described below.

When used in the evaporator 25, in FIG.
Cold water (hot water at the time of heating) flows in from the inlet 6 of the one closed chamber 5 formed by the bellows fin 1 and the side plate 4, and the cold water flows out of the outlet 7 arranged above the chamber. On the other hand, the refrigerant liquid coming from the condenser 24 is dropped from the sprayer 10 into the other chamber 8, and cools the cold water by using heat of vaporization when the refrigerant liquid becomes refrigerant vapor.

In this embodiment, since the mesh body 9A is inserted in the chamber 8 through which the refrigerant liquid passes, the wetting and spreading property of the refrigerant in the lateral direction is improved by the woven wire net 9B, and the refrigerant vapor is discharged by the expanded metal 9C. Is promoted, the refrigerant supply is improved, and the heat transfer efficiency is greatly improved. In order to obtain good wetting and spreading characteristics, the mesh size of the woven wire mesh 9B is set to mesh 30 to 50 and wire diameter 0.35 to 0.1.
It is desirable to set it to either 1 mm.

When used in the absorber 26, in FIG.
Cooling water flows from an inlet 6 of one of the hermetically sealed chambers 5 formed by the bellows fins 1 and the side plate 4, and flows out from an outlet 7 provided above the chamber 5. On the other hand, into the other chamber 8, the concentrated solution flowing from the low-temperature regenerator 23 through the low-temperature solution heat exchanger 28 is dropped from the sprayer 10, and at the same time, refrigerant vapor coming from the evaporator 25 flows in. As a result, the cooling water exchanges heat with the concentrated solution and the refrigerant vapor through the thin plate of the bellows fin 1, both of them are cooled, and the concentrated solution absorbs the refrigerant to become a dilute solution. In this case as well, the wetting and spreading properties of the refrigerant in the lateral direction are improved by the woven wire mesh 9B, and the expanded metal 9C accelerates the discharge of the dilute solution, and the concentrated solution and the refrigerant vapor are well supplied, and the heat transfer efficiency is increased. Improved. In order to obtain good wetting and spreading characteristics, the mesh size of the woven wire mesh 9B should be changed to the mesh 10
It is desirable to set it to any one of .about.20 and a wire diameter of 1.2 to 0.18 mm.

When used in the low temperature regenerator 23, in FIG. 1, a separator 22 is passed through a port 7 provided in the upper portion of one closed chamber 5 formed by the bellows fin 1 and the side plate 4. The incoming high-temperature refrigerant vapor is caused to flow in, and the refrigerant liquid is recovered from the port 6 provided in the lower portion. On the other hand, a side plate (not shown) is also provided in the other chamber 8 to be closed, and the intermediate concentrated solution passing through the high-temperature solution heat exchanger 27 is dropped from above the closed chamber 8 and flows downward. I do. As a result, the high-temperature refrigerant vapor and the intermediate concentrated solution exchange heat with each other through the thin plate of the bellows fin 1, so that the refrigerant vapor is further generated from the intermediate concentrated solution, and then the concentrated solution is recovered from below the closed chamber 8. To Also in this case, since the mesh body 9A is inserted into the chamber 8 through which the intermediate concentrated solution passes, the wetting and spreading property of the intermediate concentrated solution in the lateral direction is improved by the woven wire netting 9B, and the refrigerant vapor through the expanded metal 9C, The discharge and recovery of the concentrated solution was promoted, and the heat transfer efficiency and boiling heat transfer were greatly improved.

When this heat exchanger is used for the evaporator 25, the absorber 26, and the condenser 24, as shown in FIG. 2, in addition to the chamber 8, a chamber 5 through which cold water (or hot water) and cooling water pass. The expanded metal 11 may be inserted on the side of. By doing so, turbulent flow and stirring action are also generated in water, heat transfer efficiency is further improved, and
By inserting the expanded metal 11 into the chamber 5 and the net 9A into the chamber 8, it is possible to reduce the thermal strain generated during brazing in the furnace.

[0029]

As described above, according to the absorption refrigerating machine of the present invention, since the mesh body having a large mesh size in the central portion is inserted in the flow path of the refrigerant or the like in the heat exchange, the heat transfer surface Refrigerant and solution become difficult to flow near to improve wettability and adhesion, and near the center of the flow path, products generated by heat exchange easily flow and are easily discharged. Etc. will be promoted.
As a result, the heat transfer efficiency and heat exchange efficiency of the absorption refrigerator can be further improved.

[Brief description of the drawings]

FIG. 1 shows a schematic configuration of an embodiment of a heat exchanger of an absorption refrigerator according to the present invention, (a) is a front view when the heat exchanger is used in a vertical shape showing a vertical direction, and (b) is a front view. (A) A
FIG.

FIG. 2 is a schematic configuration diagram of another embodiment of the heat exchanger of the absorption refrigerator according to the present invention.

FIG. 3 is a schematic configuration diagram of a general absorption refrigerator.

FIG. 4 shows a schematic configuration of an embodiment of a heat exchanger of an absorption chiller according to an example of a conventional technique, (a) is a front view when the heat exchanger is used in a vertical shape showing a vertical direction, (b) is a BB arrow line view of (a).

[Explanation of symbols]

 1 bellows fin 2, 3 seal plate 4 side plate 5 chamber 6 inlet 7 outlet 8 chamber 9A reticulate body (porous layer) 9B woven wire mesh 9C, 11 expanded metal 10 spreader

Claims (4)

(57) [Claims] 1. A high temperature regenerator for heating a dilute solution with a heating source, a separator for separating the solution heated by the high temperature regenerator into a refrigerant vapor and an intermediate concentrated solution, and an intermediate concentrated solution from the separator. A high temperature solution heat exchanger for exchanging heat with a dilute solution, and an intermediate concentrated solution whose temperature has been lowered by the high temperature solution heat exchanger is reheated by a refrigerant vapor coming from the separator to further generate a refrigerant vapor from the intermediate concentrated solution. A low-temperature regenerator to form a concentrated solution, a condenser that liquefies the refrigerant vapor generated in the low-temperature regenerator into a refrigerant liquid, and a refrigerant liquid from the condenser to the cooler to cool water from the cooler. In the evaporator, an evaporator for obtaining the above, an absorber for absorbing the refrigerant vapor vaporized in the evaporator by spraying the concentrated solution that performs heat exchange from the low temperature regenerator through the low temperature solution heat exchanger, and the absorber The dilute solution that has absorbed the refrigerant is transferred to the high temperature regenerator through a heat exchanger. A corrugated bellows fin formed by continuously bending at least one of the evaporator, the absorber, and the low-temperature regenerator, and a peak and a valley of the bellows fin. In an absorption refrigerator comprising a heat exchanger consisting of a seal plate for sealing a chamber formed by a section with an end face, a chamber in which a refrigerant and / or a solution passes among the chambers is located inside both outsides. An absorption refrigerator having a porous layer with high permeability inserted therein. 2. The absorption refrigerator according to claim 1, wherein the porous layer is formed by stacking a pair of woven wire nets and an expanded metal inside the woven wire nets, and brazing the pair of woven wire nets. An absorption refrigerator that is closely attached to the surface of the heat transfer plate. 3. The absorption refrigerating machine according to claim 1, wherein when the evaporator is constituted by the heat exchanger, one of the chambers formed by the bellows fin mountain portion and the valley portion is closed, and the vertical direction. Cold water (or hot water) is introduced from below and discharged from above, and the coolant liquid is dropped into the other chamber from above the bellows fins, and the cold water (or hot water) is also added.
An absorption refrigerating machine characterized in that an expanded metal is also inserted in the chamber in which is introduced. 4. The absorption refrigerating machine according to claim 1, wherein when the absorber is constituted by the heat exchanger, one of the chambers formed by the bellows fin mountain portion and the valley portion is closed, and the vertical direction. The cooling water is introduced from below and discharged from above, and the refrigerant vapor is allowed to pass while dropping the concentrated solution from above the bellows fin to the other chamber, and the cooling water is introduced into the chamber. An absorption refrigerator with an expanded metal inserted.