JP2002090000A - Absorption refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an absorption refrigerating machine capable of improving heat exchanging performance. SOLUTION: The absorption refrigerating machine is provided with an evaporator 10 and an absorber 20, provided so that whose respective one side surfaces are opposed to the evaporator 10, to absorb and melt refrigerant gas, evaporated in the evaporator 10, into a solution in the absorber 20, and obtain high- temperature thick solution by boosting and heating thin solution from the absorber 20 while the thick solution is sent into a high-pressure regenerator to obtain further condensed thick solution and return the same into the absorber. The evaporator 10 and the absorber 20 are provided with a heat transfer tube 12, extending from the other side surface opposed to the one side surface toward the one side surface and the terminal end side of the same is turned toward the other side surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption refrigerator, and more particularly to a structure of an absorber and an evaporator.

[0002]

2. Description of the Related Art An absorption refrigerator is a refrigerator using water as a refrigerant, a lithium bromide solution as an absorbent, and gas fuel or oil fuel as an energy source. This absorption refrigerator includes an evaporator, an absorber, a regenerator, and a condenser as main members, and the inside of the evaporator and the absorber is maintained at a high vacuum.

In this evaporator, refrigerant (water) sent by a refrigerant pump is sprayed toward an evaporator tube through which cold water (for example, 12 ° C.) flows, so that the refrigerant is heated to become refrigerant vapor. . That is, since the evaporator is a high vacuum vessel, water (refrigerant) boils at about 4 to 6 ° C. and evaporates. Therefore, even cold water at 12 ° C. can be used as heat source water.

[0004] Then, the temperature of the cold water is reduced (for example, to 7 ° C) by the amount of latent heat of evaporation given to the refrigerant (water), and then leaves the evaporator. The chilled water whose temperature has been lowered (to 7 ° C.) is sent to a cooling device or the like (cooling load) of the building and used for cooling. The cold water used for cooling rises in temperature (for example, to 12 ° C.) and flows into the evaporator tube of the evaporator again.

[0005] On the other hand, in the absorber, the refrigerant vapor generated in the evaporator is absorbed by the lithium bromide solution. The lithium bromide solution (hereinafter referred to as "dilute lithium bromide solution") having absorbed water and having a reduced concentration is collected at the bottom of the absorber. In this absorber, the latent heat of condensation when the refrigerant vapor is absorbed by the lithium bromide solution and changes from gas (water vapor) to liquid (water), and when the concentration of the lithium bromide solution becomes thin due to the absorption of moisture. Since heat of dilution is generated, these heats are removed by cooling water (circulated in a different system from the above “cold water”). Note that the lithium bromide solution is a substance that is rich in hygroscopicity and suitable for absorbing the refrigerant vapor, since the water vapor partial pressure is lower than the saturated vapor of water.

In the regenerator, the lithium bromide dilute solution sent from the absorber is heated. For this reason, the refrigerant in the lithium bromide dilute solution is partially vaporized and evaporated, and the solution is concentrated lithium bromide solution (hereinafter referred to as “lithium bromide concentrated solution”).
). The lithium bromide concentrated solution whose concentration has been raised to the original state is sent to the absorber and absorbs the refrigerant vapor again. On the other hand, the evaporated refrigerant vapor is sent to the condenser.

In the actual machine, a double-effect absorption refrigerator having a regenerator arranged in two stages is employed for the purpose of increasing heat efficiency and reducing heating energy. In this double-effect absorption refrigerator, a high-pressure regenerator that heats a dilute lithium bromide solution by burning supplied fuel and a high-temperature refrigerant vapor generated by the high-pressure regenerator are used as a regenerator. And a low-pressure regenerator for heating the lithium bromide dilute solution.

[0008] In the condenser, the refrigerant vapor sent from the regenerator is cooled by cooling water and condensed and liquefied. The condensed and liquefied water is supplied again to the evaporator as a refrigerant (water).

Thus, in the absorption refrigerator, the refrigerant (water)
Changes (phase change) with water-steam-water,
The lithium bromide solution changes (concentration solution-dilute solution-concentration solution) (change in concentration). In the process of the above-described phase change (refrigerant) and concentration change (lithium bromide solution), the absorption refrigerator produces cold water by the latent heat of evaporation of water, and absorbs water vapor by the absorption capacity of the lithium bromide solution. Is repeatedly performed in a high vacuum closed system.

In such an absorption refrigerator, the amount of fuel supplied to the high-pressure regenerator is increased to increase the amount of heating, and the concentration of the lithium bromide solution is increased, so that the temperature of the cold water flowing out of the evaporator is reduced. Can be lowered. Conversely, by decreasing the amount of fuel supplied to the high pressure regenerator to reduce the amount of heating and decreasing the concentration of the lithium bromide solution, the temperature of the cold water exiting the evaporator can be increased. Thus, by adjusting the concentration of the lithium bromide solution, the temperature of the cold water is controlled, and the temperature of the cold water flowing out of the evaporator is set to the set temperature (7 ° C.).

Here, the evaporator and the absorber in the absorption refrigerator will be described. FIG. 14 schematically shows the internal structure of a conventional absorption refrigerator.

In a conventional absorption refrigerator, as shown in FIG. 14, an evaporator 101 and an absorber 102 are provided in the same shell, and an eliminator 103 is provided between the two. A low-pressure regenerator 104 is provided above the
Condensers 105 are provided adjacent to the low-pressure regenerators 104, respectively. A plurality of heat transfer tubes 112 are arranged on one side of the box-shaped case main body 107 in parallel with the eliminator 103. On the other hand, a plurality of heat transfer tubes 114 are arranged in parallel with the eliminator 103 on the other side in the box-shaped case main body 107.

In the evaporator 101, cooling water whose temperature has been increased due to cooling is flowing to a plurality of heat transfer tubes 112 as evaporator tubes. The refrigerant is heated to be a refrigerant vapor, and flows to the absorber 102 through the eliminator 103. In this absorber 102, cold water flows to a plurality of heat transfer tubes 114 as absorber tubes.
The lithium bromide solution is sprayed toward 14, and the refrigerant vapor generated in the evaporator 101 is absorbed by the lithium bromide solution. The lithium bromide solution that has absorbed the refrigerant vapor has its latent heat of dilution and heat of dilution removed by the cooling water flowing therein by contacting the heat transfer tube 114, and the low-concentration lithium bromide solution is removed from the bottom of the case body 107. Collected in.

[0014]

By the way, in the above-mentioned conventional absorption refrigerator, the heat transfer tube 112 of the evaporator 101 and the heat transfer tube 114 of the absorber 102 are formed by the eliminator 10.
3 are provided in parallel. For this reason, the refrigerant vapor flowing from the evaporator 101 to the absorber 102 is supplied to each heat transfer tube 11.
Flow in a direction perpendicular to the heat transfer tubes
Collision with 2,114. Therefore, there is a problem that the pressure loss becomes large and the heat exchange performance is low.

The present invention has been made in view of the above circumstances, and has as its object to provide an absorption refrigerator capable of improving heat exchange performance.

[0016]

According to a first aspect of the present invention, there is provided an absorber having a group of heat transfer tubes through which a cooling medium flows, and configured to spray the absorbing liquid to the group of heat transfer tubes, and a flow of a fluid to be cooled. An absorption refrigerator including a heat transfer tube group and an evaporator configured to spray the refrigerant to the heat transfer tube group, wherein one of the evaporator and the absorber is horizontally arranged in one casing. Are arranged in a direction parallel to the flow direction of the refrigerant evaporated on the evaporator side and flowing to the absorber side.

In this absorption refrigerator, since the heat transfer tubes hardly become resistant to the flow of the refrigerant in either the evaporator or the absorber, if the tube pitch is the same as the conventional one, the pressure loss will be lower than in the conventional case. If the tube pitch can be reduced while maintaining the pressure loss as it is, the apparatus can be made smaller than before.

According to a second aspect of the present invention, there is provided a heat transfer tube group through which a cooling medium flows, and an absorber configured to spray an absorbing liquid to the heat transfer tube group, and a heat transfer tube group through which a fluid to be cooled flows. In an absorption refrigerator in which an evaporator configured to spray a refrigerant to the heat transfer tube group is horizontally arranged in one casing in a casing, the evaporator and the heat transfer tube group of the absorber are each connected to the evaporator. The refrigerant is disposed in a direction parallel to a flow direction of the refrigerant that evaporates on the side and flows to the absorber side.

In this absorption refrigerator, in the evaporator and the absorber, the heat transfer tube is unlikely to become a resistance to the flow of the refrigerant gas. If the tube pitch is reduced while maintaining the pressure loss, the size of the apparatus can be reduced as compared with the conventional apparatus.

The invention described in claim 3 is the first or second invention.
In the absorption refrigerator described in 1, the heat transfer tube group of the evaporator and / or the absorber is formed on one side of the absorber or the evaporator side starting from the other side which is the anti-absorber or evaporator side. And a heat transfer tube group that is turned back on the one side surface and has a terminal end disposed on the other side surface, and the heat transfer tube group is a starting end header through which the fluid to be cooled and / or the cooling medium flows. And a connection to a terminal side header.

In this absorption refrigerator, the fluid introduced into the header on the start end side is branched into a plurality of heat transfer tubes connected to the header on the start end side. Then, the heat is returned from the plurality of heat transfer tubes to the terminal side header.

According to a fourth aspect of the present invention, in the absorption refrigerator of the third aspect, the heat transfer tube group has a U-shape whose ends are respectively connected to the start end header and the end header. It is characterized by comprising a hairpin tube bent into a shape.

In this absorption refrigerator, the cooling medium or the fluid to be cooled flows from the other side surface to one side surface, returns to a U-shape on one side surface, and returns to the terminal side header.

According to a fifth aspect of the present invention, in the absorption refrigerator of the third aspect, the heat transfer tube group is connected to the start end header on the other side, and the intermediate header is connected to the other end on one side. Are connected to each other, and are further formed of a group of heat transfer tubes connected at the intermediate header and the other end connected to the terminal side header.

In this absorption refrigerator, the cooling medium or the fluid to be cooled flows into the intermediate header from the start end header, and then turns back and flows into the end header.

The invention described in claim 6 is the invention according to claims 3 to 5
In the absorption refrigerator according to any one of the above, the start end header and the end header are provided alternately, and any one of the headers is communicated with any adjacent header via the heat transfer tube group. It is characterized by having.

In this absorption refrigerator, the fluid (the cooling medium or the fluid to be cooled) introduced into the starting end header is branched into a plurality of heat transfer tubes connected to the starting end header. Then, the fluid is returned from the plurality of heat transfer tubes to the terminal headers on both sides of the starting header, and the fluid is discharged from these terminal headers.

[0028] The invention according to claim 7 is the invention according to claims 3 to 5.
In the absorption refrigerator according to any one of the above, the start end header and the end side header are arranged side by side along the longitudinal direction of the heat transfer tube group, and one end of the heat transfer tube group is the start end header or the end side header. And is connected to one of the other headers.

In this absorption refrigerator, the fluid (cooling medium or fluid to be cooled) introduced into the heat transfer tube from the start end header passes through the start end header or the end header and then passes through the end header. Discharged.

According to an eighth aspect of the present invention, in the absorption refrigerator according to the third aspect, a plurality of heat transfer units each including the heat transfer tube group, the starting end header, and the end header are provided. The fluid to be cooled and / or the cooling medium that has flowed through the heat transfer unit is configured to flow through another heat transfer unit.

In this absorption refrigerator, the fluid (cooling medium or fluid to be cooled) flowing in the heat transfer tube in the upstream heat transfer tube unit is introduced into the downstream heat transfer tube unit, and flows again in the heat transfer tube unit. Will be done. That is, the fluid flows through the heat transfer tube a plurality of times to perform heat exchange.

According to a ninth aspect of the present invention, in the absorption refrigerator of the eighth aspect, of the plurality of heat transfer units, the downstream heat transfer unit is provided above the upstream heat transfer unit. The refrigerant or the absorbing liquid flows downward from above.

In this absorption refrigerator, while the absorbing liquid or the refrigerant flows from the upper part around the heat transfer tube, the cooling medium flows from the lower heat transfer tube unit toward the upper heat transfer tube unit in the heat transfer tube. Alternatively, the fluid to be cooled flows. Therefore, heat exchange is performed in a countercurrent manner between the absorbing liquid or the coolant outside the heat transfer tube and the cooling medium or the fluid to be cooled inside the heat transfer tube.

According to a tenth aspect of the present invention, in the absorption refrigerator according to any one of the third to ninth aspects, the heat transfer tube group includes a plurality of heat transfer tubes arranged in a vertical direction. A support member is provided between the heat transfer tubes for supporting the heat transfer tube vertically in the middle of the length direction.

In this absorption refrigerator, the heat transfer tubes are stably provided by the support members.

According to an eleventh aspect of the present invention, in the absorption refrigerator according to the tenth aspect, the support member is formed by forming the same two support portions in contact with the heat transfer tube into a circular arc-shaped convex portion. And a spacer which is coupled to face each other.

In this absorption refrigerator, since the heat transfer tube is fitted on the concave side of the arc of the support, the heat transfer tube can be stably supported.

According to a twelfth aspect of the present invention, in the absorption refrigerator according to the tenth or eleventh aspect, the heat transfer tube group comprises a plurality of heat transfer tubes arranged in a horizontal direction. And a holding member for holding a space between the plurality of heat transfer tubes.

In this absorption refrigerator, since the heat transfer tube group is held in the horizontal direction by the holding member, the heat transfer tube group is prevented from rolling and stably held.

According to a thirteenth aspect of the present invention, in the absorption refrigerator of the twelfth aspect, the holding member is formed of a plate having a plurality of holes through which the refrigerant or the absorbing liquid flows. I do.

In this absorption refrigerator, when the sprayed absorbing liquid or refrigerant drops and passes through the hole of the holding member, the absorbing liquid or refrigerant is re-dispersed and the wetting of the heat transfer tube is made uniform.

[0042]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration of an absorption refrigerator of the present embodiment, FIG. 2 is a side sectional view of an absorber and an evaporator included in the absorption refrigerator according to the first embodiment of the present invention, and FIG. FIG. 3 shows a cross-sectional view taken along the line T.

In the absorption refrigerator of the present embodiment, as shown in FIG. 1, the evaporator 10 and the absorber 20 are formed in the same shell (casing). Inside the evaporator 10, an evaporator tube group 11 is arranged. Cold water (fluid to be cooled) W1 is supplied around the evaporator tube group 11 through a cold water inlet line L1, and the cold water W1 flowing through the evaporator tube group 11 is discharged to the outside through a cold water outlet line L2. Is done. Further, the refrigerant liquid R pumped up by the refrigerant pump P1 via the refrigerant line L11 is sprayed toward the evaporator tube group 11. The sprayed refrigerant liquid R is supplied to the evaporator tube group 11.
The latent heat of vaporization is taken from the cold water W1 flowing through the inside, and the refrigerant evaporates and evaporates to become refrigerant vapor r. This refrigerant vapor r flows into the absorber 20 side.

The cold water W1 enters the evaporator 10 at a temperature of, for example, 12 ° C., is cooled by the evaporator tube group 11, and is discharged from the evaporator 10 at a temperature of, for example, 7 ° C. The 7 ° C. cold water W1 coming out of the cold water outlet line L2 is used for cooling a building or for a process in a factory. The cooling water W1 used for cooling under a cooling load such as a building cooling condition rises in temperature, reaches a temperature of 12 ° C., and flows into the evaporator 10 again.

On the other hand, an absorber tube group 21 is arranged in the absorber 20. Cooling water (cooling medium) W2 is supplied to the absorber tube group 21 via a cooling water line L3.
Then, the lithium bromide concentrated solution Y <b> 1 pumped through the solution line L <b> 21 by the solution pump P <b> 2 is sprayed toward the absorber tube group 21. For this reason, the sprayed lithium bromide concentrated solution Y1 absorbs the refrigerant vapor r flowing into the absorber 20, and the concentration is reduced. The diluted lithium bromide solution Y3 having a reduced concentration is collected at the bottom of the absorber 20. The heat generated in the absorber 20 is cooled by the cooling water W2 flowing in the absorber tube group 21.

The dilute lithium bromide solution Y3 collected at the bottom of the absorber 20 is pumped by a solution pump P3.
It is supplied to the high-pressure regenerator 40 via the valve V5, the low-temperature heat exchanger 30, the solution line L22, the high-temperature heat exchanger 31, and the solution line L23.

The high-pressure regenerator 40 accommodates a furnace tube and a heat transfer tube in a body and is equipped with a burner. This high pressure regenerator 4
0 indicates that the fuel gas G is supplied via the gas line L31, the valve V21, and the fuel control valve V22,
The fuel gas G is burned to heat the lithium bromide dilute solution Y3. Dilute lithium bromide solution Y supplied to high-pressure regenerator 40
3 is heated and a part of the refrigerant is evaporated and vaporized to form a solution Y2 in lithium bromide having a medium concentration. The solution Y2 in lithium bromide is supplied to the low-pressure regenerator 50 through the solution line L24 and the high-temperature heat exchanger 31.

On the other hand, the refrigerant vapor r evaporated in the high pressure regenerator 40 is supplied to the low pressure regenerator tube group 51 of the low pressure regenerator 50 via the refrigerant line L12.
3 to the condenser 60. Note that the low-pressure regenerator 50 and the condenser 60 are configured in the same shell.

In the low-pressure regenerator 50, the solution line L2
The solution Y2 in lithium bromide is supplied via the solution line L4, and the lithium bromide dilute solution Y3 branched from the solution line L22 via the solution line L25 is supplied to the low-pressure regenerator tube group 5
Sprayed towards 1. In this low-pressure regenerator 50, the solutions Y2 and Y3 are heated by the low-pressure regenerator tube group 51, a part of the refrigerant evaporates, the concentration of the solution further increases, and the high-concentration lithium bromide concentrated solution Y1 is subjected to low-pressure regeneration. Collected at the bottom of the vessel 50. This concentrated solution of lithium bromide Y1 is supplied to a solution pump P
By 2, it is supplied to the absorber 20 again.

The condenser 60 has a cooling water line L4
The condenser tube group 61 to which the cooling water W2 is supplied by is provided. In the condenser 60, the refrigerant vapor r that has been evaporated in the high-pressure regenerator 40 and supplied through the refrigerant line L 12, the low-pressure regenerator tube group 51, and the refrigerant line L 13, and evaporated in the low-pressure regenerator 50. The refrigerant vapor r flowing into the condenser 60 is cooled and condensed in the condenser tube group 61 to become the refrigerant liquid R. This refrigerant liquid R is sent to the evaporator 10 via the refrigerant line L14 by gravity and a pressure difference.
The refrigerant liquid R collected at the bottom of the evaporator 10 is returned to the evaporator tube group 1 via the refrigerant line L11 by the refrigerant pump P1.
Sprayed towards 1.

In the above-described absorption refrigerator, during the cooling operation, the valves V1, V2, V3, and V4 are closed (shown in black in the figure), and the valves V5, V1
1, V12, V13, and V14 are open (shown in white in the figure). Further, the absorption refrigerator can perform a heating operation, but is not related to the present invention, so that the description of the operation during the heating operation is omitted.

Next, the structure of the evaporator 10 and the absorber 20 in the above-described absorption refrigerator of the present embodiment will be specifically described. As shown in FIG. 3, the evaporator 10 and the absorber 20
Each has a plurality of heat transfer tube groups 11 and 21 in which a plurality of straight tubes are arranged in parallel in the same manner as in the conventional example, and has a rectangular outer shape. It is arranged to be. As shown in FIG. 2, the evaporator 10 is provided with two sets of upper and lower heat transfer tube units 72A and 72B in the vertical direction. The heat transfer tube units 72A and 72B each have a horizontal U-shaped tube 12,
U-shaped tubes (hairpin tubes) which are arranged in a plurality of stages in the vertical direction and in a plurality of rows in the horizontal direction.
The U-bend 12b is located on the side closer to the eliminator 71 (the start end and the end are farther away) so that the straight pipe portion 12a and the flow of the refrigerant vapor r are parallel to each other. Both the straight pipe sections 12a are arranged so that their longitudinal center lines are included in the same vertical plane.

In the heat transfer tube unit 72A, each U-shaped tube 12
The starting end is a starting end side header 73, 7 extending in the horizontal direction.
3 and 75, and the terminal end is connected to one of the terminal side headers 74, 74 also extending in the horizontal direction. The headers on both the start and end sides are arranged so that the center line is included in the same vertical plane perpendicular to the U-shaped tube 12. In addition, each starting end side header 73 is provided with a plurality of rows of connection holes for the U-shaped pipes 12 in one row and plural rows, whereas the starting end side header 75 and each end side header 74 are provided with two rows of upper and lower rows of U-shaped pipes. A connection hole is formed in the pipe 12 to reduce the number of headers.

In the heat transfer tube unit 72B, each U-shaped tube 12
The starting end is a starting end header 78, 7 extending in the horizontal direction.
8 and the terminal end is connected to one of the terminal side headers 77, 77 and 79 also extending in the horizontal direction. The headers on both the start and end sides are arranged so that the center line is included in the same vertical plane perpendicular to the U-shaped tube 12. In addition, connection holes for the upper and lower two-stage plural rows of the U-shaped tubes 12 are formed in the start end header 78 and the end header 79 to reduce the number of headers, whereas the end headers 77 and 77 are provided. Are provided with connection holes for U-tubes 12 in a plurality of rows in one stage.

Further, the starting end side headers 73, 73, 75 of the heat transfer tube unit 72A are all provided on the supply side header 76 (lower right side in FIG. 2) extending over the entire height direction of the heat transfer tube unit 72A.
Are all connected to the intermediate header 80 extending vertically in the entire height of the evaporator 10.
(Left side in FIG. 2). Further, the start end headers 78, 78 of the heat transfer tube unit 72B are all connected to the intermediate header 80, and the end headers 77, 77, 7 are connected.
9 are all connected to a discharge-side header 76 '(upper right side in FIG. 2) extending over the entire height direction of the heat transfer tube unit 72B.

With the above configuration, the cold water supplied to the evaporator 10 is supplied to the supply side header 76 of the heat transfer tube unit 72A.
After being distributed to the headers 73, 73, 75 via
Furthermore, it is distributed to each U-shaped tube 12, and then the terminal side header 7
4, 74, and further to the intermediate header 80. Next, the cold water collected in the intermediate header 80 is again supplied to the start-side headers 78 and 7 of the heat transfer tube unit 72B.
After being distributed to 8, it is further distributed to each U-shaped tube 12, subsequently collected to the end headers 77, 77 and 79, finally collected to the supply header 76 ′, and discharged out of the system. .

Although the number of stages and the length of the U-shaped tube 12 may be different, the structure of the absorber 20 is substantially the same as that of the evaporator 10 and is substantially symmetric with the evaporator 10 with the eliminator 71 interposed therebetween. Since it is located at the position, detailed description is omitted.

As shown in FIGS. 4 and 5, in the evaporator 10 and the absorber 20, the start and end of each U-shaped tube 12 are the start side headers 73, 75, 78, 78 and the end side header 7 respectively.
4, 74, 77, and 79, and the other side near the U-bend portion 12b is supported by a support member 95 described below.

That is, the support member 95 is formed of a pair of upper and lower support portions 95a, 95a having an arc-shaped cross section formed by cutting a short horizontal plumb tube at a plane parallel to the axis, and a pair of upper and lower support portions 95a. , 95a are connected and fixed at appropriate intervals, and a spacer 95b is provided. The upper supporting portion 95a is provided so that the straight pipe portion 12a of the U-shaped tube 12 is fitted and supported. 95a is a U-shaped tube 12
Are vertically symmetrical with their convex surfaces facing each other so as to be fitted and supported by the straight pipe portion 12a.

The evaporator 10 and / or the absorber 20 are provided with a plurality of re-dispersion plates (holding members) 96 made of a plate material at appropriate intervals in the vertical direction, and fix at least a part of the support members 95. The hole for dropping the refrigerant liquid R is formed not only on the entire surface but only on a portion directly below the U-shaped tube 12.

Next, the operation of the absorption refrigerator of the present embodiment will be described. In the evaporator 10, the cold water W1 is supplied to the header 76 of the heat transfer tube unit 72A via the cold water inlet line L1. The cold water W1 flows from the header 76 into the headers 73 and 75 on the start side. Then, the starting end headers 73 and 75 are discharged to the adjacent end side header 74 through the U-shaped tube 12. The cold water W1 is supplied to the terminal side header 7
4 into the header 80 and then into the heat transfer tube unit 72
B is introduced. In the heat transfer tube unit 72B, the cold water W1 is first introduced into the start headers 78, 78, and is discharged through the U-shaped tube 12 to the end headers 77, 79 adjacent to the start headers 78, 78. Termination side header 7
After flowing into the header 76 ', the cold water W1 discharged to 7, 79 is discharged to the outside through the cold water outlet line L2, and is used for cooling of a building or a process of a factory.

Here, the refrigerant liquid R is sprayed on the evaporator 10 from above as described above. Cold water W1 in U-shaped tube 12
Is flowed, the refrigerant liquid R and the cold water W1 exchange heat, and the cold water W1 in the U-shaped tube 12 is cooled. Here, since two heat transfer tube units 72A and 72B are provided in the vertical direction, the cold water W1 and the refrigerant liquid R exchange heat twice. Moreover, the cold water W1 is supplied to the lower heat transfer tube unit 7
Since the refrigerant liquid R flows from the upper heat transfer tube unit 72B to the upper heat transfer tube unit 72B and the refrigerant liquid R is dispersed downward from above, the cold water W1
The refrigerant liquid R exchanges heat countercurrently.

After the refrigerant water R in the U-shaped tube 12 evaporates and evaporates from the refrigerant liquid R into refrigerant vapor r, the refrigerant vapor r passes through the eliminator 71 and is introduced into the absorber 20. Since the refrigerant vapor r flows between the heat transfer tube units 72A and 72B and the dropped refrigerant liquid R in parallel with the heat transfer tube units 72A and 72B except for a part of the U-bend portion 12b and the like of the U-shaped tube 12, the refrigerant vapor r contacts the dropped refrigerant liquid R. Since the degree is also reduced and the flow is not significantly disturbed, the pressure loss of the refrigerant vapor r flowing through the evaporator 10 is remarkably reduced when the pipe pitch is made equal to the conventional one.

Next, the absorber 20 will be described. The flow of the cooling water (fluid) W2 in the heat transfer tube units 72A and 72B of the absorber 20 is the same as that of the evaporator 10. First, the cooling water W2 is supplied from the cooling water line L3 to the header 76, and the cooling water W2 is supplied from the header 76 to the header 7 on the starting end side.
3,75. Then, the start-side headers 73 and 75 pass through the U-shaped tube 12 and are adjacent to the end-side header 7.
4 is discharged. The cooling water W2 flows from the terminal side header 74 to the header 80, and is then introduced into the heat transfer tube unit 72B. In the heat transfer tube unit 72B, the cooling water W
2 is first introduced into the start end headers 78, 78, and the U-tube 1
2, the ink is discharged to the end headers 77, 79 adjacent to the start end headers 78, 78. Terminal header 77, 7
The cooling water W2 discharged to 9 flows into the header 76 ', and then is introduced into the condenser via the cooling water line L4.
The refrigerant vapor r introduced from the evaporator 10 to the absorber 20 is:
The water is absorbed by the sprayed lithium bromide concentrated solution Y1 and cooled by the cooling water W2 flowing in the U-shaped tube 12. Similarly to the evaporator 10, the refrigerant vapor r excluding a part of the U-shaped tube 12 such as the U-bend portion 12 b and the like,
2A and 72B and between the dripping absorbing liquid Y1 flow in parallel to them, so that the degree of contact with the dripping absorbing liquid Y1 is reduced, and the flow is significantly less disturbed. The pressure loss of the refrigerant vapor r flowing through the absorber 20 is significantly reduced.

As a result, the pressure difference between the evaporator 10 and the absorber 20 becomes extremely small, and even if the static pressure on the evaporator 10 side is the same as the conventional one, the static pressure on the absorber 20 side becomes higher, and the cooling performance becomes higher. And the heat transfer area of the absorber 20, that is, the absorber 2
0 can be made smaller.

It should be noted that the flow resistance and the pressure loss are reduced.
You may be concerned about reducing turbulence in the flow, weakening its diffusive mixing, and reducing the rate of heat and mass transfer (evaporation, absorption, etc.) for the following reasons: It can be said that it gives better results.

That is, the water vapor, which is the refrigerant vapor r, contains only a trace amount of non-condensable gas and has a pressure distribution but no concentration distribution, and there is no mass transfer resistance on the refrigerant vapor r side. As described above, as the flow resistance (pressure loss) of the refrigerant vapor r decreases and the static pressure on the absorber 20 side increases, the driving force for absorption increases, the absorption performance improves, and good results are obtained.

In the conventional type in which the refrigerant vapor flows vertically to the pipe, there is a drift due to the lateral flow of the droplets and mist entrainment. In the present invention, the straight pipe section of the U-shaped pipe 12 is used. Since the longitudinal direction of the refrigerant vapor r coincides with the longitudinal direction of the refrigerant vapor r, the first part of the U-shaped tube 12 at the very beginning and the end has a portion that is not wet with the droplet, Although a very small portion may fall off the U-bend portion 12b and fall, most fall on the U-shaped tube 12 and wet it.

Secondly, most of the refrigerant vapor r flows between the adjacent U-shaped tubes 12 and 12, so that there is almost no contact between the refrigerant and the droplets and therefore the entrainment of mist is extremely reduced.
The resulting energy loss is significantly reduced.

Further, the heat transfer between the refrigerant liquid R / absorbent liquid Y1 and the pipe mainly depends on the viscosity of the liquid, disturbance due to liquid wetting or dripping of the liquid, but the static pressure of the absorber 20 is not sufficient. As the temperature rises, the absorption capacity is improved, thereby increasing the liquid temperature and decreasing the viscosity, so that the heat conductivity is also improved. The refrigerant vapor r
Although the effects of turbulence due to the flow of water are not insignificant, it is clear from the experimental results that it is not so large.

Instead of reducing the pressure loss, the apparatus can be made smaller by reducing the pipe pitch as in the conventional case. Further, by increasing only the tube pitch on the side of the evaporator 10 having a smaller number of tubes than the absorber 20, the above-described various effects can be further increased.

In the evaporator 10 and the absorber 20, the liquid once supplied to the lower heat transfer tube unit 72A is again supplied to the upper heat transfer tube unit 72B, and the liquid which falls from above and the liquid in the pipe are mixed. Are basically cross-contacted in a cross, but have the effect of semi-countercurrent contact, so that the efficiency of heat exchange is high.

Further, the liquid that has fallen after wetting the U-shaped tube 12 is once collected on the entire re-dispersion plate 96, and the liquid depth is made uniform. Drops are evenly dropped on each U-shaped tube 12 and flow down while wetting them, so that the liquid wetting of the tubes is uniform. In addition, the re-dispersion plate 96 suppresses the mixing of the refrigerant vapor r in the vertical direction, so that a static pressure difference is generated in the vertical direction (the static pressure is low in the upper part and the static pressure is high in the lower part). Accordingly, the performance of the device is improved.

The U-shaped tube 12 is supported on one side by the headers 73, 74, 75, 77, 78 and 79, and is stably supported on the other side by a support member 95. Furthermore, since the U-shaped tube 12 is horizontally connected by the re-dispersion plate 96 via the support member 95, the U-shaped tube 12 can be prevented from rolling. Further, since the side surface of the spacer 95b is arranged to be perpendicular to the flow direction of the refrigerant vapor r, the support member 95 does not become resistant to the flow of the refrigerant vapor r.

As shown in FIGS. 6 and 7, the evaporator 10 and the absorber 20 shown in FIGS. 2 and 3 are connected to the headers 76 and 76 '.
And the header 80 may be rotated 90 degrees so as to be positioned in the vertical direction. In this example, after the fluid passes through the heat transfer tube unit 72A and undergoes heat exchange, it further passes through the heat transfer tube unit 72B. That is, heat is exchanged between the refrigerant R or the lithium bromide concentrated solution Y1 and the fluid in the U-shaped tube 12 in two stages. Therefore, heat is efficiently exchanged. In addition, in this example, the same effect as in the first embodiment can be obtained.

Next, a second embodiment of the present invention will be described.
This will be described with reference to FIGS. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. FIG. 8 is a vertical sectional view of the absorber and the evaporator of the absorption refrigerator of the present embodiment, and FIG. 9 is a sectional view taken along line TT of FIG. As shown in FIG. 8, the evaporator 10 'includes a heat transfer tube unit 81A at a lower portion and a heat transfer tube unit 81B at an upper portion. The heat transfer tube unit 81A is located on a side surface of the evaporator 10 'facing the eliminator 71, and is provided with a start end header 82, a header 83, and a straight pipe portion 12a' having a different length.
Heat transfer tube unit 81B
Are located on the same side, and a header 83 and a terminal side header 84
And a U-shaped tube 12 '. The start-side header 82 and the end-side header 84 are vertically connected, and further,
A header 83 is provided on the inner side of the evaporator 10 ′ with respect to the start-side header 82 and the end-side header 84, in contact with the start-side header 82 and the end-side header 84.

As described later, in the heat transfer tube unit 81A, the header 83 functions as a terminal side header, and in the heat transfer tube unit 81B, the header 83 functions as a start side header. The start-side header 82 and the end-side header 84 are respectively connected to the header 83 by the U-shaped tube 12 '. More specifically,
In the heat transfer tube unit 81 </ b> A, one end of the U-shaped tube 12 ′ is connected to the starting end side header 82 while penetrating the header 83 as the end side header, and the other end of the U-shaped tube 12 ′ is connected to the header 83. ing. The heat transfer tube unit 81
In B, one end of the U-shaped tube 12 ′ is connected to the terminal side header 84 while penetrating the header 83 as the start side header, and the other end is connected to the header 83.

The absorber 20 'has the same configuration as the evaporator 10'. That is, the absorber 20 'includes the heat transfer tube units 81A and 81B in the vertical direction. Heat transfer tube units 81A and 81B of evaporator 10 'and absorber 2
The heat transfer tube units 81 </ b> A and 81 </ b> B of 0 ′ are arranged facing each other with the eliminator 71 interposed therebetween.

Next, the operation of the absorption refrigerator of the present embodiment will be described. In the evaporator 10 ', the cold water W1 is supplied to the starting end header 82 of the heat transfer tube unit 81A via the cold water inlet line L1. Fluid flows from the start end header 82 into the U-tube 12 '. Then, it is discharged to the header 83 through the U-shaped tube 12 '. The cold water W1 has a header 83
It rises inside and flows into the heat transfer tube group heat transfer tube unit 81B. In the heat transfer tube group heat transfer tube unit 81B, the cold water W
1 passes through the U-shaped tube 12 ′ connected to the header 83 and is discharged to the terminal side header 84. Then, the cold water outlet line L
The air is discharged to the outside via the air conditioner 2 and is used for cooling of a building or a process of a factory. In the absorber 20 ', the cooling water W2 is introduced from the cooling water line L3 into the heat transfer tube unit 81A, and flows in the U-shaped tube 12' like the evaporator 10 '. Thereafter, it is introduced into the condenser 60 via the cooling water line L4. Other operations are the same as those in the first embodiment.

In the absorption refrigerator of the present embodiment, the U-tube 1
2 ′ penetrates the header 83, the first
The number of headers can be drastically reduced as compared with the embodiment. After the fluid passes through the heat transfer tube unit 81A and undergoes heat exchange, it further passes through the heat transfer tube unit 81B. That is, the refrigerant liquid R or the lithium bromide concentrated solution Y1
And the fluid in the U-shaped tube 12 undergoes heat exchange in two stages. Therefore, heat is efficiently exchanged. In addition, in this example, the same effect as in the first embodiment can be obtained.

Next, a third embodiment of the present invention will be described.
A description will be given based on FIGS. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. FIG. 10 is a vertical sectional view of the absorber and the evaporator of the absorption refrigerator of the present example, and FIG. 11 is a sectional view taken along line TT of FIG. As shown, the evaporator 10 ″ includes a heat transfer tube unit 85A at a lower portion and a heat transfer tube unit 85B at an upper portion.
As shown at 0, a starting end header 86 and an ending side header 87 are provided side by side, and each of the starting end header 86 and the ending side header 87 includes a plurality of straight pipes (heat transfer tubes) 88. One ends of the tube groups 88A and 88B are connected. The other end of each pipe 88 is connected to an eliminator 71.
In the vicinity, it is connected to one intermediate header 89. Thus, the pipes 88 are in communication with each other. The intermediate header 89 has an elliptical or rectangular cross-sectional view that is long in the horizontal direction and short in the vertical direction, and reduces the flow resistance of the refrigerant vapor r. The pipe 88 and the intermediate header 89 constitute a heat transfer tube extending from one side surface of the evaporator 10 ″ toward the eliminator 71 and having a terminal side folded back to one side surface side.

In the heat transfer tube unit 85B, a start end header 90 and a termination end header 91 are provided side by side like the heat transfer tube unit 85A. Heat transfer tube unit 85A
The end header 91 of the heat transfer tube unit 85B is located above the start header 86 of the heat transfer tube unit, and the start header 9 of the heat transfer tube unit 85B is located above the end header 87 of the heat transfer tube unit 85A.
0 are located respectively. The end header 87 and the start header 90 are in communication.

The absorber 20 "has the same configuration as the evaporator 10". That is, the absorber 20 "is provided with heat transfer tube units 85A and 85B in the vertical direction. A partition plate 92 is provided to partition the inner space of the evaporator 10" and the absorber 20 "into left and right. A re-dispersion plate 96 that partitions in the direction is provided.

Next, the operation of the absorption refrigerator of this embodiment will be described. In the evaporator 10 ″, the cold water W1 is supplied to the start end header 87 of the heat transfer tube unit 85A via the cold water inlet line L1. The fluid flows from the start end header 87 to the pipe 88. Then, the fluid passes through the intermediate header 89. The cold water W1 is discharged to the terminal header 87. The cold water W1 flows from the terminal header 87 into the start header 90 of the heat transfer tube unit 85B.In the heat transfer tube unit 85B, the cold water W1 is connected to the pipe 88 connected to the start header 90. Through the intermediate header 89 and discharged to the end side header 91. Thereafter, the water is discharged to the outside through the cold water outlet line L2, and is used for cooling of a building or a process of a factory.
In the absorber 20 ", the cooling water W2 is introduced into the heat transfer tube unit 85A from the cooling water line L3, and the evaporator 10"
Flows in the U-shaped tube 12 in the same manner as in the above. Thereafter, it is introduced into the condenser 60 via the cooling water line L4. Other operations are the same as those in the first embodiment.

In the absorption refrigerator of this embodiment, the structure is simplified because the pipe 88 is connected to the tubular intermediate header 89. After the fluid passes through the lower heat transfer tube unit 85A and undergoes heat exchange, it further passes through the upper heat transfer tube unit 85B. That is, the refrigerant liquid R or the lithium bromide concentrated solution Y1 and the fluid in the U-tube 12
Contact countercurrent in stages. Therefore, heat is efficiently exchanged. Further, the space inside the evaporator 10 ″ and the absorber 10 ″ is vertically and horizontally partitioned by the re-dispersion plate 96 and the partition plate 92, and mixing of the refrigerant vapor r between the partitioned spaces is prevented. The discharged liquid is not biased, and the heat exchange efficiency is improved. In addition, in this example, the same effect as in the first embodiment can be obtained.

In each of the above embodiments, two heat transfer tube units are provided and heat exchange is performed in two stages. However, the number of heat transfer tube units is not limited to the above, and may be three.
Heat exchange may be performed by providing at least two stages. Also, the re-dispersion plate 9
The number 6 is not limited to the above examples.

Further, as shown in FIG. 12, a straight heat transfer tube 99 is employed on the side of the absorber 20 (20 ', 20 "), and this heat transfer tube 99 is connected to the eliminator 7 in a conventional manner.
1 may be provided substantially in parallel. On the side of the evaporator 10, the evaporators 10, 10 ′, and 10 ″ described in each of the above examples can be adopted. In this case, in the absorber 20, the concentrated lithium bromide solution Y1 dropped into the U-tube It becomes easy to come into contact with the refrigerant vapor r before coming into contact with the refrigerant vapor 12, and the absorption action easily progresses.Moreover, the temperature of the diluted lithium bromide solution Y3 is increased, and the cooling water W2 flowing in the straight heat transfer tube 99 is formed. And the heat exchange efficiency can be increased.

Further, in each of the above embodiments, as shown in FIG.
A may be provided. As the configuration of the evaporator 10A, the evaporators 10, 10 ', and 10 "shown in each of the above embodiments can be adopted. In this example, the sum of the volumes of the two evaporators 10A is the evaporator in each of the above embodiments. 10, 10 ', 10 "
And the same volume. Absorber 20 and each evaporator 10
The distance between the refrigerant vapor A and the refrigerant vapor r flowing into the absorber 20 from the evaporator 10A can be greatly reduced. Therefore, pressure loss can be significantly reduced, thereby improving heat exchange efficiency.

[0089]

As described above, the present invention has the following effects. According to the invention as set forth in claims 1 to 7, since the heat transfer tubes are arranged in substantially the same direction as the flow of the refrigerant, the heat transfer tubes are unlikely to be resistant to the flow of the refrigerant, and the tube pitch is the same as the conventional one. Then, the pressure loss can be reduced as compared with the related art, and the efficiency of heat exchange can be improved. Further, by reducing the tube pitch while keeping the pressure loss as it is, the apparatus can be made smaller than before.

According to the eighth aspect of the present invention, since the fluid flows through the heat transfer tube a plurality of times, heat exchange is performed more reliably, and the performance of the apparatus is improved. According to the ninth aspect of the present invention, heat is exchanged in a countercurrent manner between the fluid flowing from the lower part to the upper part in the heat transfer tube unit and the fluid outside the heat transfer tube, so that the efficiency is further improved. Can be done.

According to the tenth and eleventh aspects of the present invention,
By providing the support member, the heat transfer tube can be stably supported. According to the twelfth aspect of the invention, by providing the holding member, the heat transfer tube can be stably held by preventing the heat transfer tube from rolling. According to the thirteenth aspect of the present invention, the fluid sprayed in the evaporator or the absorber passes through the hole of the holding member while falling, so that the fluid is redispersed and the wetting of the heat transfer tube is made uniform. , Heat exchange efficiency is improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing the overall configuration of an absorption refrigerator shown as an embodiment of the present invention.

FIG. 2 is a side sectional view of an absorber and an evaporator of the absorption refrigerator shown as the first embodiment of the present invention.

FIG. 3 is a sectional view taken along the line TT in FIG. 2;

FIG. 4A is a side view of a support member used for the absorber and the evaporator, and FIG. 4B is a front view of the same.

FIG. 5 is a diagram showing an attached state of a re-dispersion plate used in the absorber and the evaporator.

FIG. 6 is a side sectional view of an absorber and an evaporator shown as a modification of the embodiment.

FIG. 7 is a horizontal sectional view taken along the line TT of FIG. 6;

FIG. 8 is a vertical sectional view of an absorber and an evaporator of an absorption refrigerator shown as a second embodiment of the present invention.

FIG. 9 is a horizontal sectional view taken along line TT in FIG. 8;

FIG. 10 is a vertical sectional view of an absorber and an evaporator of an absorption refrigerator shown as a third embodiment of the present invention.

FIG. 11 is a horizontal sectional view taken along line TT in FIG. 10;

FIG. 12 shows an absorber and an evaporator of an absorption refrigerator shown as another embodiment according to the present invention.

FIG. 13 shows an absorber and an evaporator of an absorption refrigerator shown as another embodiment according to the present invention.

FIG. 14 is a schematic configuration diagram of a conventional absorption refrigerator.

[Explanation of symbols]

 10, 10 ', 10 "evaporator 20, 20', 20" absorber 12 U-shaped tube (heat transfer tube) 72A, 72B Heat transfer tube unit 73, 75 Start end header 74 End end header 77, 79 End end header 78 Start end Side header 81A, 81B Heat transfer tube unit 82 Start end header 83 Header 84 End side header 85A, 85B Heat transfer tube unit 86 Start end header 87 End side header 88 Piping 89 Intermediate header 90 Start end header 91 End side header 95 Support member 96 Re Dispersion plate (holding member)

Claims (13)

[Claims] 1. An absorber comprising a group of heat transfer tubes through which a cooling medium flows, and configured to spray an absorbing liquid to the group of heat transfer tubes; and a group of heat transfer tubes through which a fluid to be cooled flows. In an absorption refrigerator in which an evaporator configured to be sprayed is horizontally arranged in a single casing in a casing, one of the heat transfer tube groups of the evaporator or the absorber is evaporated on the evaporator side. An absorption refrigerator arranged in a direction parallel to a flow direction of the refrigerant flowing toward the absorber. 2. An absorber comprising a group of heat transfer tubes through which a cooling medium flows, and configured to spray an absorbing liquid to the group of heat transfer tubes, and a group of heat transfer tubes through which a fluid to be cooled flows. An absorption refrigerator in which an evaporator configured to be sprayed and arranged horizontally in one casing in a casing, wherein the heat transfer tube group of the evaporator and the absorber evaporates on the evaporator side and the absorber An absorption refrigerating machine characterized by being arranged in a direction parallel to a flow direction of a refrigerant flowing to a side. 3. The absorption refrigerator according to claim 1, wherein the heat transfer tube group of the evaporator and / or the absorber is absorbed starting from the other side that is the anti-absorber or evaporator side. A heat transfer tube group extending on one side, which is a vessel or evaporator side, and turned back on the one side to constitute a heat transfer tube group disposed on the other side, and the heat transfer tube group includes the fluid to be cooled and And / or an absorption refrigerator connected to a start end header and an end header through which a cooling medium flows. 4. The absorption refrigerator according to claim 3, wherein the heat transfer tube group is formed by a U-shaped bent hairpin tube whose ends are connected to the start end header and the end header, respectively. An absorption refrigerator. 5. The absorption refrigerator according to claim 3, wherein the heat transfer tube group is connected to the starting end header on the other side surface, and connected to the intermediate header on the other side surface on the other side. An absorption refrigerator comprising a heat transfer tube group further folded back at an intermediate header and connected at the other end to the terminal side header. 6. The absorption refrigerator according to claim 3, wherein the start-side header and the end-side header are provided alternately,
An absorption refrigerator in which one of the headers is connected to the other adjacent header via the heat transfer tube group. 7. The absorption refrigerator according to claim 3, wherein the start-side header and the end-side header are arranged side by side along a longitudinal direction of the heat transfer tube group. An absorption refrigerator in which one end penetrates one of the start-side header and the end-side header and is connected to one of the other headers. 8. The absorption refrigerator according to claim 3, wherein a plurality of heat transfer units each including the heat transfer tube group, the start end header and the end header are provided, and one heat transfer unit is circulated. An absorption refrigerator, wherein the fluid to be cooled and / or the cooling medium is circulated to another heat transfer unit. 9. The absorption refrigerator according to claim 8, wherein, of the plurality of heat transfer units, a downstream heat transfer unit is provided above an upstream heat transfer unit, and the refrigerant or the absorbing liquid is provided. An absorption refrigerator characterized by flowing down from above. 10. The absorption refrigerator according to claim 3, wherein the heat transfer tube group includes a plurality of heat transfer tubes arranged in a vertical direction, and the heat transfer tube group is provided between the vertical heat transfer tubes. An absorption refrigerator comprising a support member for vertically supporting a heat transfer tube in a longitudinal direction thereof. 11. The absorption refrigerator according to claim 10, wherein the support member is combined with a support portion having an arc-shaped cross section in contact with the heat transfer tube and the two support portions having a convex surface of an arc facing each other. An absorption refrigerator comprising: 12. The absorption refrigerator according to claim 10, wherein the heat transfer tube group is composed of a plurality of heat transfer tubes arranged in a horizontal direction, and between the plurality of heat transfer tubes arranged in a horizontal direction. An absorption refrigerator comprising a holding member for maintaining a distance between the two. 13. The absorption refrigerator according to claim 12, wherein the holding member is formed of a plate having a plurality of holes through which the refrigerant or the absorption liquid flows.