JP3836930B2 - Evaporator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an evaporator having a structure in which liquid refrigerant is sprayed on an outer surface of a vertically installed cylinder.
[0002]
[Prior art]
Conventionally, an evaporator having a structure in which a liquid refrigerant is sprayed and evaporated on an outer surface of a vertically installed pipe to cool the liquid flowing in the pipe is known. In such a structure, since the evaporation area of the liquid refrigerant can be widened with respect to the size of the evaporator, the evaporator can be made compact.
[0003]
[Problems to be solved by the invention]
However, when the liquid refrigerant is not sprayed over the entire outer surface of the pipe and is sprayed partially, the evaporation area cannot be used effectively and sufficient performance cannot be obtained. In order to prevent such a bias, a configuration is known in which liquid refrigerant is sprayed onto the outer surface of the tube by spraying. However, the configuration becomes complicated and requires a pump to obtain the spray output from the spray. Problems such as cost and cost increase arise.
[0004]
In addition, since the pipe is erected vertically, the liquid refrigerant sprayed on the outer surface of the pipe flows down directly, so the time until it flows down is short and the liquid refrigerant does not evaporate sufficiently, and sufficient performance is obtained. There was a problem that it was not possible. For this reason, a configuration using a grooved pipe in which longitudinal and lateral grooves are formed on the entire outer surface of the tube is known, but it is not possible to obtain a sufficient effect only by spreading in the vicinity of the portion where the liquid refrigerant flows.
The evaporator of the present invention is intended to solve the above-described problems and increase the evaporation efficiency of the evaporator.
[0005]
[Means for Solving the Problems]
The evaporator according to claim 1 of the present invention for solving the above-mentioned problems is
In the evaporator provided in the absorption type air conditioner and spraying and evaporating the liquid refrigerant on the outer surface of the vertically installed cylinder, and cooling the liquid flowing in the cylinder,
The gist is that a spirally wound coil is mounted on the outer surface of the cylinder.
[0006]
The evaporator according to claim 2 of the present invention for solving the above-mentioned problems is
In the evaporator provided in the absorption type air conditioner and spraying and evaporating the liquid refrigerant on the outer surface of the vertically installed cylinder, and cooling the liquid flowing in the cylinder,
Retaining means for storing the liquid refrigerant on the upper outer periphery of the cylinder,
The retention means is provided with a plurality of spray holes evenly on the bottom surface along the outer periphery of the cylinder.
[0007]
The evaporator according to claim 1 of the present invention having the above-described configuration cools the liquid flowing in the cylinder by spraying and evaporating the liquid refrigerant on the outer surface of the vertically installed cylinder. By installing a spirally wound coil on the outer surface of the cylinder, the dispersed liquid refrigerant flows down spirally along the coil, so that the outer surface of the tube can be used effectively and the time until it flows down Can be lengthened.
[0008]
The evaporator according to claim 2 of the present invention having the above-described configuration is provided with a staying means for accumulating liquid refrigerant on the upper outer periphery of the cylinder, and a plurality of spray holes are provided uniformly along the outer periphery of the cylinder on the bottom surface. Therefore, the accumulated liquid refrigerant can be flowed almost uniformly from the spray hole to the entire circumference of the cylinder.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
In order to further clarify the configuration and operation of the present invention described above, preferred embodiments of the evaporator of the present invention will be described below.
FIG. 1 is a schematic configuration diagram of an absorption air conditioner as an embodiment of the present invention. This absorption-type air conditioner is a low-concentration lithium bromide aqueous solution (hereinafter simply referred to as a low-concentration solution, an intermediate-concentration solution, A high-temperature regenerator 10 that heats the high-concentration solution), a first gas-liquid separator 11 that separates the low-concentration solution heated by the high-temperature regenerator 10 into water vapor and intermediate-concentration solution, and fin-tube heat exchange The low-temperature regenerator 20 that reheats the intermediate concentration solution flowing in the vessel 20a with water vapor from the first gas-liquid separator 11, and the intermediate concentration solution heated by the low-temperature regenerator 20 is separated into water vapor and high-concentration solution. A second gas-liquid separator 21, a condenser 30 that cools and liquefies the water vapor from the second gas-liquid separator 21, and a double pipe portion 40 that integrally forms an evaporator and an absorber are provided.
In addition, although not shown in figure, the fan for ventilating to the condenser 30 and the double pipe part 40 is provided.
[0010]
The high-temperature regenerator 10 and the low-temperature regenerator 20 are instantaneous heating systems that heat the lithium bromide aqueous solution flowing through the fin tube heat exchangers 10a and 20a, respectively, and the lithium bromide aqueous solution required in the apparatus as compared with the boiler system. Therefore, the thermal efficiency at the time of heating the solution is good, and the start-up time at the start of operation is fast.
[0011]
The condenser 30 is formed by vertically laying a plurality of cylindrical pipes having longitudinal and lateral grooves formed on the entire inner surface and providing fins on the outside. The surface area in the condenser 30 is widened by the groove on the inner surface, and the water vapor can be efficiently cooled by blowing air from the fan.
[0012]
As shown in FIG. 2, the double pipe portion 40 includes a cold water pipe 41 that circulates a refrigerant (water in this embodiment) of an indoor unit (not shown) and an outer pipe 42 that is formed outside the cold water pipe 41. Is done. An evaporation absorption chamber 43 is formed between the cold water pipe 41 and the outer pipe 42. An annular water receiving tray 44 is provided on the outer surface of the cold water pipe 41 of the evaporation absorption chamber 43, and a water spray nozzle 45 for dropping water sent from the condenser 30 and the low temperature regenerator 20 is provided on the upper portion thereof.
[0013]
As shown in FIG. 3, a plurality of spray holes 44 a penetrating the bottom surface are evenly arranged on the bottom surface of the water receiving tray 44 along the outer periphery of the cold water pipe 41. In the case of a small amount of water, the spray hole 44a has such a size that it does not flow downward due to the surface tension of the water itself, and water is pushed out by the water pressure when the water level in the water receiving tray 44 becomes high. Therefore, the amount of water flowing out from the spray holes 44a can be substantially stabilized, and water can be flowed from all the spray holes 44a almost evenly. Further, a grooved pipe in which vertical and horizontal grooves are formed on the entire outer surface is used for a portion of the cold water pipe 41 in the evaporation absorption chamber 43. By using a grooved pipe, it is easy to permeate water into the outer surface to slow down and flow down easily. Further, a spirally wound coil 48 is mounted on the outer periphery so as to be in contact with the outer surface of the cold water pipe 41. A portion of the water sprayed from the spray hole 44a is spirally guided by the coil 48, the outer surface of the cold water pipe 41 is effectively used, and the time until it reaches the lower part is further increased, so that the sprayed water can be reliably obtained. To evaporate.
[0014]
Similarly, an annular solution receiver 46 is also provided on the inner surface of the outer tube 42 of the evaporation absorption chamber 43, and a solution spray nozzle that drops the high-concentration solution separated by the second gas-liquid separator 21 onto the solution receiver 46. 47 is provided. A plurality of spray holes 46 a penetrating the bottom surface of the solution receiving tray 46 are evenly arranged along the inner surface of the outer tube 42. Further, the inner surface of the outer tube 42 is roughened by shot blasting or the like. By roughing the surface in this way, the solution can easily penetrate and the flow-down speed is slowed and spread easily. Further, a lath net 49 rounded into a cylindrical shape is inserted so as to be in contact with the inner surface of the outer tube 42, and the sprayed high-concentration solution is spread left and right, and the liquid retaining property is enhanced.
[0015]
In the solution circulation path 50 from the evaporation absorption chamber 43 to the high-temperature regenerator 10, heat exchange with the high-concentration solution sent from the circulation pump 51 that circulates the low-concentration solution to the high-temperature regenerator 10 and the second gas-liquid separator 21. A low-temperature heat exchanger 52 for performing heat exchange, and a high-temperature heat exchanger 53 for exchanging heat with the intermediate concentration solution sent from the first gas-liquid separator 11 are provided.
[0016]
The first gas-liquid separator 11 and the second gas-liquid separator 21 are provided with overflow pipes 60 and 70, respectively, and are connected to the solution circulation path 50. The overflow pipes 60 and 70 are provided with thermal valves 61 and 71 that close the flow paths when the solution temperature in the gas-liquid separators 11 and 21 becomes a predetermined temperature or higher, respectively.
[0017]
Next, the operation of this absorption type air conditioner will be described. When the low-concentration solution flowing through the finned tube heat exchanger 10a is heated by the combustion heat of the burner 1 in the high-temperature regenerator 10, the first gas-liquid separator 11 separates the water-vapor and intermediate-concentration solution. The separated intermediate-concentration solution is supplied to the low-temperature regenerator 20 after the temperature is lowered by the high-temperature heat exchanger 53, and is caused by water vapor from the first gas-liquid separator 11 when flowing in the fin tube heat exchanger 20a. Reheated and separated into water vapor and high-concentration solution by the second gas-liquid separator 21. After the temperature of the high-concentration solution is lowered by the low-temperature heat exchanger 52, the high-concentration solution is dropped onto the solution receiving tray 46 from the solution spray nozzle 47 and passes along the inner surface of the outer tube 42 from the plurality of spray holes 46 a provided in the solution receiving tray 46. Be sprayed. The dispersed high-concentration solution is spread over the entire inner surface by the lath net 49.
[0018]
Further, the water vapor is cooled and condensed by air from a fan (not shown) in the condenser 30 to become water, and is dropped onto the water receiving tray 44 from the water spray nozzle 45 together with the water condensed in the low temperature regenerator 20. And when water accumulates in the water tray 44, the water is pushed out from the plurality of spray holes 44a and sprayed almost evenly around the entire circumference of the cold water pipe 41. The sprayed water flows down and a part of the water is guided spirally by the coil 48. At that time, water convects and the entire water comes into contact with the cold water pipe 41, so that heat transfer is improved. In this way, water flows over the entire outer surface of the cold water pipe 41 and further spreads in the vicinity thereof by the grooved pipe, so that the entire outer surface can be effectively used.
[0019]
The heat corresponding to the heat of vaporization is taken from the circulating water flowing through the cold water pipe 41 by the evaporated water and cooled. In the indoor unit, the cooling operation is performed using the circulating water circulating in the cold water pipe 41. The evaporated water vapor is immediately absorbed by the high concentration solution on the inner surface of the outer tube 42. At this time, the high-concentration solution generates absorption heat on the inner surface of the outer tube 42, but is cooled by blowing air from a fan (not shown). The high-concentration solution absorbs water vapor to become a low-concentration solution, and is sent to the low-temperature heat exchanger 52 and the high-temperature heat exchanger 53 by the circulation pump 51 to raise the temperature, and then heated by the high-temperature regenerator 10.
[0020]
As described above, according to the absorption air conditioner of the present embodiment, the following effects are produced.
1. By spraying water from the plurality of spray holes 44a arranged evenly along the outer periphery of the cold water pipe 41, the evaporation area of water can be widened, so that the evaporation efficiency can be increased. In addition, since the water is pushed out by being accumulated, the amount of water flowing out from the spray hole 44a can be almost stabilized, and water can be made to flow almost uniformly from the entire spray hole 44a. Obtainable. Moreover, since it can be realized with a simple configuration, the cost can be reduced.
2. Evaporation efficiency can be increased by guiding a part of the water sprayed from the spray hole 44a by the coil 48 in a spiral manner, making effective use of the outer surface of the cold water pipe 41 and further increasing the time to reach the lower part. . Further, since the coil 48 can be realized with a simple configuration in which the coil 48 is provided on the outer surface of the cold water pipe 41, the cost can be reduced.
3. Since the structure can be simplified by a simple configuration in which evaporation and absorption are performed in the evaporation absorption chamber 43 formed between the cold water pipe 41 and the outer pipe 42, the apparatus can be made smaller and the weight can be reduced. Can reduce the cost. Further, by performing evaporation and absorption on the opposite surfaces of the evaporation absorption chamber 43, the water vapor is smoothly absorbed by the high concentration solution, and the chilled water pipe 41 is cooled from the surroundings, which is efficient.
4). Since the high-temperature regenerator 10 and the low-temperature regenerator 20 are instantaneous heating systems using finned tube heat exchangers 10a and 20a, respectively, the amount of lithium bromide aqueous solution required in the apparatus can be reduced compared to the boiler system. The rise time at the start of operation can be shortened, and the weight of the instrument can be reduced. Moreover, the heat efficiency at the time of heating a solution is good by a fin tube type heat exchanger.
[0021]
Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention.
For example, although the present embodiment has been described using a cooling device, for example, a cooling / heating device in which a heating operation is performed by switching the spraying locations of the high-concentration solution and water may be used.
In the present embodiment, the grooved pipe is used for the cold water pipe 41, but the present invention is not limited to this, and for example, a smooth pipe may be used.
Further, the evaporator is not limited to the double tube structure in which the absorber is integrated, and the liquid refrigerant is sprayed and evaporated along the outer surface of the vertically installed cylinder to cool the liquid flowing in the cylinder. Any evaporator can be used.
Further, the refrigerant and the absorbing liquid are not limited to water and lithium bromide.
[0022]
【The invention's effect】
As described above in detail, according to the evaporator according to claim 1 of the present invention, the evaporation efficiency of the liquid refrigerant is increased by effectively using the outer surface of the pipe and increasing the time until the liquid refrigerant flows down. Therefore, the cooling performance can be increased. Further, the cost can be reduced due to the simple configuration of mounting the coil.
[0023]
Furthermore, according to the evaporator according to claim 2 of the present invention, the liquid refrigerant can be made to flow almost uniformly over the entire circumference of the cylinder, so that the evaporation efficiency of the liquid refrigerant can be increased, so that the cooling performance can be increased. . Further, the cost can be reduced due to the simple configuration.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an absorption air conditioner as one embodiment.
FIG. 2 is a cross-sectional view of a double pipe portion.
FIG. 3 is a perspective view of a cold water pipe.
[Explanation of symbols]
10 ... High temperature regenerator, 20 ... Low temperature regenerator, 30 ... Condenser, 40 ... Double pipe part,
41 ... Cold water pipe, 42 ... Outer pipe, 43 ... Evaporation absorption chamber, 44 ... Water tray,
44a ... spray hole, 48 ... coil.

Claims (2)

In the evaporator provided in the absorption type air conditioner and spraying and evaporating the liquid refrigerant on the outer surface of the vertically installed cylinder, and cooling the liquid flowing in the cylinder,
An evaporator comprising a spirally wound coil mounted on the outer surface of the cylinder. In the evaporator provided in the absorption type air conditioner and spraying and evaporating the liquid refrigerant on the outer surface of the vertically installed cylinder, and cooling the liquid flowing in the cylinder,
Retaining means for storing the liquid refrigerant on the upper outer periphery of the cylinder,
The evaporator characterized in that the staying means has a plurality of spray holes evenly on the bottom surface thereof along the outer periphery of the cylinder.

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