JPH11351697A - Heat exchanger and absorption refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cooling performance in an absorption refrigerating machine with water as a refrigerant and a lithium bromide solution as an absorbent. SOLUTION: A box body is mounted on both sides of a case body 70, a plurality of heat transfer pipes 74 are penetrated into the case body 70 horizontally and are arranged in a zigzag, at the same time each end part is projected in each box body with openings, the inside is partitioned into a plurality of rooms that are aligned up and down, absorber 20 is constituted so that heat is exchanged between a lithium bromide concentrated solution Y1 which has absorbed a refrigerant vapor (r) that has flowed to the base body 70 from an evaporator and cold water that circulates a plurality of heat transfer pipes 74, and the space of a group of pipes T at an outer-periphery part is set larger than that of a group of pipes S at a center part being constituted of a plurality of heat transfer pipes 74.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an absorption refrigerator using water as a refrigerant and a lithium bromide solution as an absorbent, and an absorber as a heat exchanger applied to the absorption refrigerator or the like. .

[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 a high vacuum (having an absolute pressure of 6
７7 mmHg).

In this evaporator, refrigerant (water) sent by a refrigerant pump is sprayed toward an evaporator tube through which cold water (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, so that cold water at 12 ° C. can be used as the heat source water.

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

[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, as a regenerator, a high-pressure regenerator that heats a dilute solution of lithium bromide by burning supplied fuel and a high-temperature refrigerant vapor generated by the high-pressure regenerator are heated. A low-pressure regenerator for heating the dilute lithium bromide solution as a source.

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

As described above, 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-mentioned 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 reducing 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. 4 schematically shows the internal structure of a conventional absorption refrigerator.

In a conventional absorption refrigerator, as shown in FIG. 4, an evaporator 101 and an absorber 102 are provided in the same shell, and a gas-liquid separator 103 is provided between the two. The low-pressure regenerator 104 is provided above the absorber 102.
Are provided adjacent to each other. A plurality of heat transfer tubes 112 penetrate in the horizontal direction and are arranged in a lattice shape on one side in the box-shaped case main body 111, and each end projects and opens into a box (not shown). The box body is divided into a plurality of rooms by a horizontal partition plate 113, thereby forming a meandering evaporator tube for flowing cold water. On the other hand, on the other side of the box-shaped case body 111, a plurality of heat transfer tubes 114 are arranged in a zigzag manner so as to penetrate in the horizontal direction, and each end protrudes and opens into a box (not shown). Then, a horizontal partition 115
By dividing into a plurality of rooms, a meandering absorber tube for flowing cold water is formed.

Therefore, in the evaporator 101, the cold water used for cooling and whose temperature has risen flows to the plurality of heat transfer tubes 112 as the evaporator tubes, and when the refrigerant is sprayed toward the heat transfer tubes 112, This refrigerant is heated to become refrigerant vapor,
It flows through the gas-liquid separator 103 to the absorber 102. In this absorber 102, cold water flows to a plurality of heat transfer tubes 114 as absorber tubes, and a lithium bromide solution is sprayed toward the heat transfer tubes 204, and refrigerant vapor generated in the evaporator 101 is discharged. Is absorbed by the lithium bromide solution. Therefore, the lithium bromide solution that has absorbed the refrigerant vapor is
By contacting the cooling water 4, latent heat of condensation and heat of dilution are removed by the cooling water flowing inside, and the lithium bromide solution having a low concentration is collected at the bottom of the case body 111.

[0014]

In the above absorption refrigerator, in the absorber 102, the lithium bromide solution is sprayed toward the absorber tube (heat transfer tube 204) through which cold water flows, and the evaporator 101 generates the lithium bromide solution. As the refrigerant vapor flows, the lithium bromide solution adhering to the absorber tube absorbs the refrigerant vapor while being cooled by the cold water flowing through the inside, and the latent heat of condensation and the heat of dilution are removed. However, the plurality of heat transfer tubes 112 of the absorber 102 are densely arranged in a staggered manner so that the lithium bromide solution sprayed from above is securely attached. Therefore, each adjacent heat transfer tube
The intervals of 112 are narrow, and each heat transfer tube 11 flows from the evaporator 101
The flow velocity of the refrigerant vapor flowing between the two becomes faster. Then, the lithium bromide solution sprayed by the flow of the refrigerant vapor is blown away without adhering to the heat transfer tube 112, and there is a problem that the refrigerant vapor cannot be absorbed and the absorption performance is reduced. .

Further, since the space between the heat transfer tubes 112 of the absorber 102 is narrow, the heat transfer tubes 112 become a resistance of the refrigerant vapor flowing from the evaporator 101, and a pressure loss occurs to reduce the pressure of the refrigerant vapor. I will. As the pressure of the refrigerant vapor increases, the pressure difference from the pressure of the lithium bromide solution cooled by the cold water increases, and the refrigerant vapor absorption capacity improves, and the pressure drop of the refrigerant vapor due to the occurrence of pressure loss Causes a reduction in absorption capacity.

Further, in the absorption refrigerator, hydrogen gas may be generated during operation, or non-condensable gas may enter from the outside. If such non-condensable gas accumulates inside, the heat transfer efficiency decreases. Therefore, it is discharged to the outside using a bleeding device. In the absorber 102, bleeding is performed using an ejector mechanism or the like. However, this non-condensable gas stops at a place where the refrigerant vapor does not flow (bleeding point). Conventionally, a suction pipe extends to this bleeding point. To extract non-condensable gas. However, if the plurality of heat transfer tubes 114 are arranged in a staggered manner close to each other, it is unknown where this bleed point is, and it is necessary to perform flow analysis and set the bleed point.
It was troublesome.

The present invention solves such a problem, and an object of the present invention is to provide a heat exchanger and an absorption refrigerator having improved performance.

[0018]

According to a first aspect of the present invention, there is provided a heat exchanger comprising: a box-shaped case body; and a pair of left and right box bodies attached to both sides of the case body. A plurality of heat transfer tubes that penetrate the case body in the horizontal direction and are arranged in a staggered manner, and each end protrudes and opens into each of the boxes, and the insides of the pair of boxes are arranged vertically. A partition plate for partitioning into a plurality of rooms, wherein heat is generated between a first fluid flowing through the case body and a second fluid flowing through the plurality of rooms and the plurality of heat transfer tubes. In a heat exchanger performing exchange, a distance between adjacent heat transfer tubes in a tube group constituted by the plurality of heat transfer tubes is made larger at an outer peripheral portion with respect to a central portion of the tube group. It is.

In the heat exchanger according to the second aspect of the present invention, the heat transfer tubes at the center of the tube group are arranged in a staggered manner, while the heat transfer tubes at the outer periphery of the tube group are arranged in a lattice shape. Features.

Further, in the absorption refrigerator according to the third aspect of the present invention, the refrigerant is sprayed toward an evaporator tube through which cold water whose temperature has been raised for cooling is circulated, thereby evaporating the refrigerant to form a refrigerant vapor. Evaporator, an absorber for absorbing the refrigerant vapor generated by the evaporator with a highly concentrated lithium bromide solution, and heating the low-concentration lithium bromide solution, which has absorbed the refrigerant, to a low concentration, by using combustion gas to produce an odor. A regenerator for evaporating a refrigerant in a lithium bromide solution to supply a lithium bromide solution with a high concentration to the absorber, and supplying a refrigerant condensed by condensing refrigerant vapor generated in the regenerator to the evaporator. In an absorption refrigerator including a condenser, the absorber is:
A pair of left and right boxes is attached to both sides of the box-shaped case body, a plurality of heat transfer tubes are horizontally arranged in a zigzag penetrating through the case body, and each end projects into each of the box bodies. Lithium bromide solution that has been opened, and the inside of the box is divided into a plurality of chambers arranged vertically one above the other by a partition plate, and the lithium bromide solution that has absorbed refrigerant vapor flowing from the evaporator to the case body and the plurality of chambers And configured to perform heat exchange between the cooling water flowing through the plurality of heat transfer tubes, the distance between mutually adjacent heat transfer tubes in the tube group constituted by the plurality of heat transfer tubes, The outer peripheral portion is made larger than the central portion.

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic side view showing the internal structure of an absorption refrigerator according to a first embodiment of the present invention, FIG. 2 is a schematic front view showing the internal structure of the absorption refrigerator of this embodiment, and FIG. FIG. 4 shows a schematic configuration of the absorption refrigerator of the present embodiment.

In the absorption refrigerator of the present embodiment, as shown in FIG. 4, the evaporator 10 and the absorber 20 are formed in the same shell (high vacuum vessel). Inside the evaporator 10, an evaporator tube 11 is arranged. The evaporator tube 11 is supplied with cold water W through a cold water inlet line L1.
1 and the cold water W1 flowing through the evaporator tube 11
Is discharged outside through the cold water outlet line L2. The refrigerant (water) R pumped up by the refrigerant pump P1 via the refrigerant line L11 is sprayed toward the evaporator tube 11. The sprayed refrigerant R takes the latent heat of vaporization from the cold water W1 flowing in the evaporator tube 11, evaporates and vaporizes, and becomes refrigerant vapor r. This refrigerant vapor r is supplied to the absorber 2
It flows into the zero side.

The cold water W1 is heated at a temperature of 12 ° C.
0, cooled by the evaporator tube 11, and discharged from the evaporator 10 at a temperature of 7 ° C. Cold water outlet line L2
The cold water W1 of 7 ° C. coming out of the chiller 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, the absorber tube 2 is provided in the absorber 20.
1 is arranged. Cooling water W2 is supplied to the absorber tube 21 via a cooling water line L3. Then, the lithium bromide concentrated solution Y1 pumped by the solution pump P2 via the solution line L21 is sprayed toward the absorber tube 21. For this reason, the sprayed lithium bromide concentrated solution Y1 absorbs the refrigerant vapor r flowing into the absorber 20, and its concentration becomes thin. 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 21.

The lithium bromide dilute 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 has a furnace tube and a heat transfer tube housed in its 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 51 of the low-pressure regenerator 50 via the refrigerant line L12, and is further supplied to the condenser 60 via the refrigerant line L13. Supplied to 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
4, the solution Y2 in lithium bromide is supplied, and the dilute lithium bromide solution Y3 branched from the solution line L22 via the solution line L25 is sprayed toward the low-pressure regenerator tube 51. In this low-pressure regenerator 50,
The solutions Y2 and Y3 are heated by the low-pressure regenerator tube 51, a part of the refrigerant evaporates, and the concentration of the solution further increases,
A high concentration lithium bromide concentrated solution Y1 is collected at the bottom of the low pressure regenerator 50. The lithium bromide concentrated solution Y1 is supplied to the absorber 20 again by the solution pump P2.

The condenser 60 has a cooling water line L4
A condenser tube 61 to which the cooling water W2 is supplied is disposed. In the condenser 60, the refrigerant is evaporated in the high-pressure regenerator 40 and the refrigerant line L12 and the low-pressure regenerator tube 51
The refrigerant vapor r supplied through the refrigerant line L13 and the refrigerant vapor r evaporated in the low-pressure regenerator 50 and flowing into the condenser 60 are cooled and condensed in the condenser tube 61, and the refrigerant is cooled. (Water) becomes R. The refrigerant R is supplied to the evaporator 10 via the refrigerant line L14 by the gravity and the pressure difference.
Sent to The refrigerant R collected at the bottom of the evaporator 10 is
The refrigerant is again sprayed toward the evaporator tube 11 via the refrigerant line L11 by the refrigerant pump P1.

In the above-mentioned absorption refrigerator, during the cooling operation, the valves V1, V2, V3, 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.

Here, the structure of the absorber 20 in the above-described absorption refrigerator of the present embodiment will be specifically described.

As shown in FIGS. 1 and 2, the evaporator 10 and the absorber 20 are formed in the same shell, and a gas-liquid separator 71 is provided at a substantially central portion of a box-shaped case body 70. It has been divided into both. On the absorber 20 side, box bodies 72 and 73 are attached to both sides of the case main body 70, and a plurality of heat transfer tubes 74 constituting the absorber tube 21 penetrate in the horizontal direction in the case main body 70 and are staggered. Arranged in a shape,
Each end protrudes and opens into each of the boxes 72 and 73.
The inside of one of the boxes 72 is vertically arranged by two partition plates 75a and 75b along the horizontal direction.
The inside of the other box 73 is partitioned into two rooms B and D vertically arranged side by side by one partition plate 76a extending in the horizontal direction. Further, a cooling water supply port 77 communicating with the room A below the box 72 is provided, and a cooling water discharge port 78 communicating with the room E above is provided.

Therefore, the cold water W2 is supplied to the room A of the box 72 from the cold water inlet line L3 through the supply port 77. The cooling water W2 is passed from the room A through the group of the heat transfer tubes 74 to the room of the box 73. B, further flows to the rooms C, D, and E through the heat transfer tubes 74, and is discharged to the cooling water line L4 through the discharge port 78. On the other hand, the lithium bromide concentrated solution Y1 is sprayed toward the heat transfer tube 74 and adheres to the outer surface, so that it is cooled by the cooling water W2 flowing inside, and the refrigerant vapor r generated in the evaporator 10 is separated by the gas-liquid separator 71. , And the refrigerant vapor r is absorbed by the lithium bromide concentrated solution Y1, where the latent heat of condensation and the heat of dilution are removed to reduce the concentration of the lithium bromide dilute solution Y3 to a low concentration. Are collected at the bottom of the case body 70.

In the present embodiment, the absorber 20 is provided as shown in FIG.
As shown in detail, the plurality of heat transfer tubes 74 are arranged in a staggered manner, but in a tube group constituted by the plurality of heat transfer tubes 74, the distance between the adjacent heat transfer tubes 74 is
The outer periphery is larger than the center of the tube bank. That is, the tube groups S at the center are densely arranged, and the tube groups T at the outer periphery are densely arranged.
Are spaced apart from each other.

Therefore, in the tube group T in the outer peripheral portion of the absorber 20, the heat transfer tubes 74 are spaced apart from each other because the heat transfer tubes 74 are spaced apart from each other. Therefore, the flow rate of the refrigerant vapor r flowing from the evaporator 10 through the gas-liquid separator 71 becomes slow, and the lithium bromide concentrated solution Y1 is not blown off by the flow of the refrigerant vapor r, but is reliably transmitted. The lithium bromide concentrated solution Y1 can be attached to the heat pipe 74, and is cooled by the cold water W2 passing through the heat transfer pipe 74, so that the refrigerant vapor r can be efficiently absorbed. On the other hand, in the tube group S in the central part of the absorber 20, the heat transfer tubes 74 are closely arranged because the heat transfer tubes 74 are densely arranged. Therefore, the remaining refrigerant vapor r passing between the tube groups T
Is increased, and is reliably absorbed by the lithium bromide concentrated solution Y1 attached to the heat transfer tube 74.

The tube group T at the outer periphery of the absorber 20
Since the distance between the heat transfer tubes 74 is wide, the heat transfer tubes 74 have little resistance to the refrigerant vapor r flowing from the evaporator 10, and the pressure loss is reduced, so that the pressure drop of the refrigerant vapor r can be suppressed. Therefore, a decrease in the pressure of the refrigerant vapor r due to the occurrence of the pressure loss is reduced, and a decrease in the absorption capacity can be suppressed.

Further, the non-condensable gas generated in the absorber 20 stays in a place where the refrigerant vapor r does not flow (extraction point). In the present embodiment, the tube group T on the outer peripheral portion is separated. Since the pipe groups S are arranged densely and arranged in the center, the center of the pipe group S can be predicted as the bleed point. Therefore, the bleed point can be set without performing the flow analysis, and the suction pipe for the non-condensable gas can be easily provided.

FIG. 5 is a sectional view showing an arrangement of tube groups of an absorber in an absorption refrigerator according to a second embodiment of the present invention.

In this embodiment, as shown in detail in FIG. 5, the plurality of heat transfer tubes 74 arranged in the center are arranged in a zigzag pattern in the absorber 20 and arranged on the outer periphery. By arranging the tube groups W of the plurality of provided heat transfer tubes 74 in a lattice shape, the distance between the heat transfer tubes 74 adjacent to each other is increased in the outer peripheral portion with respect to the central portion of the tube group. That is, the tube group S in the central part
Are arranged densely, and the tube group W on the outer peripheral portion is spaced apart.

Therefore, in the tube group W in the outer peripheral portion of the absorber 20, the heat transfer tubes 74 are arranged in a lattice, so that the interval between the heat transfer tubes 74 is wide. Therefore, the flow rate of the refrigerant vapor r flowing from the evaporator 10 is reduced, and the sprayed lithium bromide solution Y1 is not blown off by the flow of the refrigerant vapor r, but is reliably attached to the heat transfer tube 74. The refrigerant vapor r can be efficiently absorbed. On the other hand, in the tube group S at the center of the absorber 20, the heat transfer tubes 74 are arranged in a staggered manner, so that the intervals between the heat transfer tubes 74 are narrow. Therefore, the remaining refrigerant vapor r passing between the tube groups T
Is increased, and the lithium bromide concentrated solution Y1 is surely absorbed.

The tube group T on the outer peripheral portion of the absorber 20
Since the distance between the heat transfer tubes 74 is wide, the heat transfer tubes 74 have little resistance to the refrigerant vapor r, the pressure loss is reduced, and the decrease in the pressure of the refrigerant vapor r can be suppressed. for that reason,
The decrease in the pressure of the refrigerant vapor r due to the occurrence of the pressure loss is reduced, and the decrease in the absorption capacity can be suppressed.

In the first embodiment, a plurality of heat transfer tubes 74 are arranged in a zigzag pattern in the absorber 20, and the tube groups S at the central portion are densely arranged. In the second embodiment, the tube groups S in the central portion are arranged in a staggered manner, while the tube groups W in the outer peripheral portion are arranged in a lattice, so that they are adjacent to each other. The distance between the heat transfer tubes 74 is made larger at the outer peripheral portion with respect to the center portion of the tube group. However, the present invention is not limited to this configuration, and the plurality of heat transfer tubes 74 are arranged in a staggered or lattice shape. The heat transfer tubes 74 may be arranged so as to gradually increase the distance between the adjacent heat transfer tubes 74 from the center to the outer periphery. Further, in each of the above-described embodiments, the heat exchanger of the present invention is applied to the absorber 20. However, the heat exchanger may be applied to the condenser 60 and other heat exchangers.

[0044]

As described in detail in the above embodiment, according to the heat exchanger of the first aspect of the present invention, a pair of left and right boxes are attached to both sides of the box-shaped case main body, and a plurality of heat transfer tubes are formed. It penetrates horizontally through the case body and is arranged in a staggered manner, and each end protrudes and opens into each box body, and the inside of the box body is divided into a plurality of rooms vertically arranged by a partition plate. The heat exchanger is configured to perform heat exchange between the first fluid flowing in the case body and the second fluid flowing through the plurality of rooms and the plurality of heat transfer tubes, and the plurality of heat transfer tubes The distance between the heat transfer tubes adjacent to each other in the tube group is made larger at the outer peripheral portion with respect to the central portion of the tube group. Fluid 1 has pressure loss with heat transfer tube hardly causing resistance The flow rate is reduced and the flow rate is reduced. On the other hand, since the central tube group is narrowly spaced, the flow rate of the remaining first fluid flowing to the central portion is increased and the heat exchange performance can be improved. .

According to the heat exchanger of the second aspect of the present invention, the heat transfer tubes at the center of the tube group are arranged in a staggered manner, while the heat transfer tubes at the outer periphery of the tube group are arranged in a lattice shape. The tube group at the outer peripheral portion is widened, and the first fluid flowing into the case body is reduced in pressure loss with little resistance of the heat transfer tube, and the flow velocity is reduced. The tube group becomes narrower in interval, and the flow rate of the remaining first fluid flowing to the central portion becomes faster, so that the performance of heat exchange can be improved.

According to the absorption refrigerator of the third aspect of the present invention, the refrigerant is sprayed toward the evaporator tube through which the chilled water whose temperature has risen by using for cooling is circulated, thereby evaporating and evaporating the refrigerant. An evaporator that produces vapor, an absorber that absorbs refrigerant vapor generated in the evaporator with a lithium lithium bromide solution having a high concentration, and a lithium bromide solution that absorbs a refrigerant and becomes low concentration by heating with a combustion gas A regenerator that evaporates the refrigerant in the lithium bromide solution and supplies the lithium bromide solution with a high concentration to the absorber, and a condenser that condenses refrigerant vapor generated in the regenerator and condenses the refrigerant to the evaporator Constitutes an absorption refrigerator, a pair of left and right boxes are attached to both sides of a box-shaped case main body, and a plurality of heat transfer tubes penetrate the case main body in a horizontal direction and are arranged in a staggered manner. With each end inside each box It protrudes and opens, and the inside of the box is divided into a plurality of rooms vertically arranged by a partition plate, and the lithium bromide solution absorbing the refrigerant vapor flowing from the evaporator to the case body and the plurality of rooms and the plurality of rooms. Heat exchange between the cooling water flowing through the heat transfer tube of
The distance between the heat transfer tubes adjacent to each other in the tube group constituted by a plurality of heat transfer tubes is made larger at the outer peripheral portion with respect to the central portion of the tube group, so that the distance between the heat transfer tubes at the outer peripheral portion in the absorber is large. Therefore, the flow rate of the refrigerant vapor flowing from the evaporator is reduced, so that the sprayed lithium bromide solution is not blown off by the refrigerant vapor, and the decrease in the refrigerant vapor pressure due to the pressure loss is suppressed. The cooling medium can adhere to the cooling medium and efficiently absorb the refrigerant vapor, while the space between the heat transfer tubes in the center is narrow, so that the flow velocity of the remaining refrigerant vapor becomes fast, and the odor adhering to the heat transfer tubes is reduced. Will be surely absorbed by the lithium chloride solution,
The absorption capacity can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic side view illustrating an internal structure of an absorption refrigerator according to a first embodiment of the present invention.

FIG. 2 is a schematic front view showing the internal structure of the absorption refrigerator of the present embodiment.

FIG. 3 is a cross-sectional view illustrating an arrangement of tube groups in the absorber according to the present embodiment.

FIG. 4 is a schematic configuration diagram of an absorption refrigerator of the present embodiment.

FIG. 5 is a cross-sectional view illustrating an arrangement of tube groups of an absorber in an absorption refrigerator according to a second embodiment of the present invention.

FIG. 6 is a schematic view showing the internal structure of a conventional absorption refrigerator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Evaporator 20 Absorber 21 Absorber tube 30 Low temperature heat exchanger 31 High temperature heat exchanger 40 High pressure regenerator 50 Low pressure regenerator 60 Condenser 70 Case body 74 Heat transfer tube 75a, 75b, 76a Partition plate 77 Supply port 78 Discharge port S, T, W Tube group P1 Refrigerant pump P2, P3 Solution pump L1 Cold water inlet line L2 Cold water outlet line L3, L4 Cooling water line L11-L15 Refrigerant line L21-L25 Solution line L31 Gas (fuel) line R Refrigerant (water) r Refrigerant vapor Y1 Lithium bromide concentrated solution Y2 Lithium bromide solution Y3 Lithium bromide dilute solution W1 Cold water W2 Cooling water G Fuel gas

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Makoto Fujiwara 2-1-1, Shinhama, Arai-cho, Takasago-shi, Hyogo Inside the Mitsubishi Heavy Industries, Ltd. Takasago Research Laboratory

Claims (3)

[Claims] 1. A box-shaped case main body, a pair of left and right box bodies attached to both sides of the case main body, and are arranged in a zigzag manner so as to penetrate the case main body in a horizontal direction and have respective ends. A plurality of heat transfer tubes projecting and opening into each of the box bodies, and a partition plate for partitioning the inside of the pair of box bodies into a plurality of vertically arranged rooms, respectively, and flows into the case body. In a heat exchanger that performs heat exchange between a first fluid and a second fluid flowing through the plurality of rooms and the plurality of heat transfer tubes, the heat exchangers are adjacent to each other in a tube group formed by the plurality of heat transfer tubes. A heat exchanger characterized in that the distance between the heat transfer tubes is made larger at the outer periphery than at the center of the tube group. 2. The heat exchanger according to claim 1, wherein the heat transfer tubes at the center of the tube group are arranged in a staggered manner, and the heat transfer tubes at the outer peripheral portion of the tube group are arranged in a lattice shape. And heat exchanger. 3. An evaporator that sprays a refrigerant toward an evaporator tube through which cold water whose temperature has risen for use in cooling is circulated, thereby evaporating the refrigerant to form a refrigerant vapor, and the evaporator generates the refrigerant vapor. An absorber for absorbing the refrigerant vapor with a lithium bromide solution having a high concentration, and heating the lithium bromide solution having a low concentration by absorbing the refrigerant with a combustion gas to evaporate the refrigerant in the lithium bromide solution to thereby stench the odor. A regenerator that supplies a lithium halide solution with a high concentration to the absorber, and an absorption refrigerator including a condenser that condenses refrigerant vapor generated in the regenerator and supplies the condensed refrigerant to the evaporator, The absorber is provided with a pair of left and right boxes on both sides of a box-shaped case main body, a plurality of heat transfer tubes are horizontally arranged in a zigzag through the inside of the case main body, and the respective ends are each Protruding into the box Lithium bromide solution that has been opened, and the inside of the box is divided into a plurality of chambers arranged vertically one above the other by a partition plate, and the lithium bromide solution that has absorbed refrigerant vapor flowing from the evaporator to the case body and the plurality of chambers And configured to perform heat exchange between the cooling water flowing through the plurality of heat transfer tubes, the distance between mutually adjacent heat transfer tubes in the tube group constituted by the plurality of heat transfer tubes, An absorption refrigerator having a larger outer peripheral portion than a central portion.