JP5733866B1 - Refrigerant heat exchanger - Google Patents

Abstract

Provided is a refrigerant heat exchanger that reliably prevents liquid back to the compressor without increasing manufacturing cost, reduces pressure loss of refrigerant gas, reduces power loss, and reduces the amount of refrigerant. To do. A refrigerant heat exchanger includes a first inlet port through which a first refrigerant is introduced, a first outlet port from which a first refrigerant vaporized inside is led out, and a second refrigerant port. A cylindrical hollow container 50 in which an inlet 70 and a second outlet 76 are formed, and a plate that is disposed inside and forms a heat exchange channel for the first refrigerant and the second refrigerant on the front and back surfaces. A hollow housing 68 having a polymer 52, a refrigerant gas introduction hole and a refrigerant gas outlet pipe 66 formed in the upper surface wall in the upper space, and a refrigerant inlet path 74 and a refrigerant outlet path 80 of a second refrigerant are provided. The upper surface wall of the hollow housing is disposed opposite to the inner surface of the upper wall and extends in the axial direction of the cylindrical hollow container, and the refrigerant gas introduction hole is formed in the axial direction of the cylindrical hollow container on the upper surface wall. A plurality are provided at intervals. [Selection] Figure 2

Description

  The present invention relates to a refrigerant heat exchanger used in a refrigerator or the like constituting a refrigeration cycle.

  The refrigerator constituting the refrigeration cycle is provided with an evaporator and a condenser. The evaporator exchanges heat between the refrigerant and the object to be cooled, and the refrigerant cools the object to be cooled by taking the latent heat of evaporation from the object to be cooled. The condenser exchanges heat between the vaporized refrigerant and cooling water or outside air, and cools and liquefies the refrigerant with cooling water or outside air. In a refrigerator having a primary refrigerant circuit and a secondary refrigerant circuit constituting a refrigeration cycle, the primary refrigerant circuit and the secondary refrigerant circuit are connected via a full-liquid evaporator (cascade condenser), and heat exchange of these refrigerants is performed. The primary refrigerant and the secondary refrigerant exchange heat with each other. In such a refrigerant heat exchanger, the primary refrigerant takes the evaporation latent heat from the secondary refrigerant and vaporizes.

  Patent Document 1 discloses a full liquid evaporator. In this full liquid evaporator, the refrigerant vaporized in the hollow container is sucked into a suction pipe connected to the inlet of the compressor. A baffle plate is provided at the inlet of the suction pipe to prevent the liquid refrigerant from entering.

  Patent Document 2 discloses a full liquid refrigerant evaporator composed of a shell-and-plate heat exchanger with good heat exchange efficiency. In this evaporator, a filter type droplet separator is provided in a conduit that guides the vaporized refrigerant to a compressor. In addition, a filler is filled in the space between the side wall of the hollow container and the plate polymer.

  Patent Document 3 also discloses a shell-and-plate refrigerant heat exchanger having the same configuration as Patent Document 2. This refrigerant heat exchanger is also provided with a filter type droplet separator at the inlet of a conduit for leading the vaporized refrigerant to the compressor. Patent Document 4 also discloses a shell-and-plate refrigerant heat exchanger. This refrigerant heat exchanger is configured such that a demister is provided at an inlet for sucking the refrigerant, and the gas-liquid separation of the refrigerant is performed by the demister.

JP 2005-502016 gazette International Publication No. 2012/107645 International Publication No. 1997/045689 JP 2011-196582 A

  When the refrigerant heat exchanger is used as a refrigerant evaporator, it is necessary to prevent liquid back from entering the compressor with liquid refrigerant. However, the droplet separation method using the baffle plate disclosed in Patent Document 1 does not have a very good droplet separation effect when the distance from the evaporation liquid surface cannot be sufficient. Therefore, there is a possibility that liquid back to the compressor occurs.

  On the other hand, the filter-type droplet separator disclosed in Patent Document 2 or Patent Document 3 has a good droplet separation effect, but a large pressure loss is likely to occur, which may increase the power of the refrigerator. Further, the demister that performs gas-liquid separation of the refrigerant described in Patent Document 4 is relatively expensive and increases the manufacturing cost.

  In view of the problems of the conventional technology, the present invention reliably prevents liquid back to the compressor without increasing the manufacturing cost, reduces the pressure loss of the refrigerant gas, reduces the power loss, and the amount of the refrigerant. It aims at realizing the refrigerant | coolant heat exchanger which can reduce this.

In order to achieve the above object, a refrigerant heat exchanger according to the present invention includes a first inlet through which a first refrigerant is introduced, a first outlet through which a first refrigerant vaporized inside is derived, and a second outlet. A cylindrical hollow container formed with a second inlet through which the refrigerant is introduced and a second outlet through which the second refrigerant is derived;
A plate polymer that is arranged inside the hollow container and on which front and back surfaces are stacked with a large number of plates on which concavities and convexities that form heat exchange channels for the first refrigerant and the second refrigerant are formed;
A hollow housing having a refrigerant gas introduction pipe connected to the first outlet and a refrigerant gas introduction hole formed in an upper surface wall of the upper space of the plate polymer so as to face the upper partition wall of the hollow container;
A refrigerant introduction path connecting the second inlet and the heat exchange flow path of the second refrigerant, and a refrigerant outlet path connecting the heat exchange flow path of the second refrigerant and the second outlet. Prepared,
The upper wall of the hollow housing is disposed in close proximity to the inner surface of the upper partition wall and extends in the axial direction of the cylindrical hollow container,
The refrigerant gas introduction hole is a refrigerant heat exchanger provided in the upper surface wall with a plurality of intervals in the axial direction of the cylindrical hollow container ,
The plate constituting the plate polymer has a radius of curvature centered on a position (S) below the axis (O) of the hollow container, with the plate below the axis (O) of the hollow container. And is formed in a semicircular shape along the vicinity of the inner wall surface of the hollow container, and the plate above the axis (O) of the hollow container is centered on the axis (0) of the hollow container A semi-elliptical shape having a radius of curvature larger than the radius of curvature is characterized .

According to this invention, the spaces s1 and s2 between the hollow container and the plate polymer can be narrowed. Thus, the hollow container can be reduced in size by reducing the gaps s1 and s2 between the outer periphery of the plate and the inner wall surface b of the hollow container. Therefore, coupled with the downsizing of the hollow container, the manufacturing cost of the refrigerant heat exchanger can be reduced.

The refrigerant heat exchanger of the present invention is originally a shell-and-plate heat exchanger with good heat exchange efficiency, and has an advantage that the amount of refrigerant to be used can be reduced by the amount of good heat exchange efficiency. Further, in the above configuration, the first refrigerant gas vaporized by heat exchange with the second refrigerant in the heat exchange flow path formed in the plate polymer rises and bypasses the hollow housing from below the hollow housing, The refrigerant flows into the hollow housing from the refrigerant gas introduction hole arranged to face the upper partition wall surface of the hollow container. While the first refrigerant gas passes through such a long bypass flow path, the droplets contained in the first refrigerant gas are separated by gravity, so that the droplet separation effect can be improved and the liquid back to the compressor is prevented. it can. The upper wall of the hollow housing is disposed in opposition to the inner surface of the upper partition wall so as to extend in the axial direction of the cylindrical hollow container, and the refrigerant gas introduction hole is formed on the upper wall of the cylindrical hollow container. A plurality are provided with intervals in the direction. For this reason, the distance between the plate polymer and the top wall can be increased. Accordingly, the flow path through which the first refrigerant gas vaporized by heat exchange reaches the upper wall becomes long, and the droplets contained in the first refrigerant gas are separated by gravity while passing through this flow path. Can do. Accordingly, a refrigerant heat exchanger can be realized in which the droplet separation effect is further improved and the liquid back to the compressor can be surely prevented. In addition, since a demister is not used for droplet separation, the manufacturing cost can be reduced.

  Further, since the filter type droplet separator disclosed in Patent Document 2 or Patent Document 3 is not provided in the middle of the flow path where the first refrigerant gas rises and reaches the refrigerant gas introduction hole, the pressure loss Can be reduced. Therefore, the COP of the refrigerator incorporating the refrigerant heat exchanger of the present invention can be improved.

  Further, in addition to the above configuration, the hollow housing extends in the axial direction of the hollow container while being opposed to the upper partition wall of the hollow container, is connected to the first inlet, and is formed on the lower surface of the hollow housing. It is possible to further include a refrigerant distribution tube provided in the longitudinal direction and having a distribution hole for distributing the first refrigerant to the plate polymer.

  Thereby, since the first refrigerant liquid can be uniformly distributed in the axial direction with respect to the plate polymer and widely spread on the upper surface of the plate polymer, the heat exchange efficiency between the first refrigerant and the second refrigerant can be improved. Therefore, the supply amount of the first refrigerant to the hollow container can be reduced, and the first refrigerant amount of the entire primary refrigerant circuit can be reduced.

  Further, as one embodiment of the present invention, two rows for vertically partitioning a space formed between a side partition of a hollow housing and the plate polymer and fixing the plate polymer to the hollow container These stays are provided, and the space between the two rows of stays and filled with the first refrigerant liquid can be filled with the filler. Thereby, the supply amount of the 1st refrigerant | coolant supplied to a hollow container can be reduced.

  Furthermore, as one embodiment of the present invention, the cross section of the hollow housing can be formed in a rectangular shape composed of a long side in the horizontal direction and a short side in the vertical direction. Accordingly, a long bypass channel can be formed before the first refrigerant reaches the first outlet, and the droplet separation effect can be improved by the baffle plate effect. Further, since the hollow housing does not protrude downward, the volume of the hollow container can be reduced, and the supply amount of the first refrigerant can be reduced accordingly. Moreover, since the cross section of the hollow container is expanded in the lateral direction, the pressure loss of the first refrigerant can be reduced, and thereby the power of the compressor provided on the downstream side can be reduced.

  Furthermore, as one embodiment of the present invention, a large number of spray holes formed in the coolant spray pipe can be arranged in the axial direction of the coolant spray pipe. Thereby, since the first refrigerant liquid can be uniformly distributed in the axial direction with respect to the plate polymer and widely spread on the upper surface of the plate polymer, the heat exchange efficiency between the first refrigerant and the second refrigerant can be improved.

  Furthermore, as one embodiment of the present invention, the refrigerant gas introduction holes can be arranged in two rows on the upper wall of the hollow housing so as to be axially symmetrical with respect to the axial direction of the hollow housing. Thereby, the pressure loss when the first refrigerant flows into the hollow housing can be reduced.

  Furthermore, as one embodiment of the present invention, the hollow housing and the refrigerant distribution tube can be formed integrally. This facilitates the attachment of the hollow housing and the refrigerant spray tube to the hollow container. Furthermore, as one embodiment of the present invention, the shape of the plate constituting the plate polymer is asymmetric in the vertical direction with respect to a horizontal line passing through the axis of the hollow container in the axial direction of the hollow container. The plate below the axis of the container may be formed in a circular shape along the vicinity of the inner wall surface of the hollow container, and the plate above the axis of the hollow container may be formed in a flat shape. . As a result, the gap between the plate below the horizontal line and the inner wall surface of the hollow container can be reduced, and the hollow container can be reduced in size. Therefore, it is not necessary to fill the gap between the outer periphery of the plate and the inner wall surface of the hollow container, and the manufacturing cost of the refrigerant heat exchanger can be reduced in combination with the miniaturization of the hollow container.

According to the present invention, the spaces s1 and s2 between the hollow container and the plate polymer can be narrowed. Thus, the hollow container can be reduced in size by reducing the gaps s1 and s2 between the outer periphery of the plate and the inner wall surface b of the hollow container. Therefore, coupled with the downsizing of the hollow container, the manufacturing cost of the refrigerant heat exchanger can be reduced.

It is the whole air-conditioning equipment lineblock diagram concerning one embodiment of the present invention. It is a front cross-sectional view of the CO ₂ liquefier incorporated in the air-conditioning equipment. It is a left side view of the CO ₂ liquefier. It is a right side sectional view taken along the line A-A of the CO ₂ liquefier. It is a partially enlarged cross-sectional view of the CO ₂ liquefier shown in Fig. It is a top view of a hollow housing provided in the CO ₂ liquefier. It is a right side sectional view taken along the line A-A of the CO ₂ liquefier according to implementation embodiments of the present invention.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention to that unless otherwise specified.

Next, an embodiment in which the present invention is applied to a CO ₂ liquefier constituting air conditioning equipment in a server room will be described with reference to FIGS. FIG. 1 is an overall configuration diagram of an air conditioning facility 10 according to the present embodiment. The air conditioning facility 10 includes a primary refrigerant circuit 12 that constitutes a refrigeration cycle, and a secondary refrigerant circuit 14 that performs air conditioning of the server room 34. In the primary refrigerant circuit 12, NH ₃ refrigerant circulates as a primary refrigerant, and as a device constituting the refrigeration cycle, a compressor 16, an evaporative condenser (evaporator) 18, an NH ₃ receiver 20, an expansion valve 22 and CO _{2 are used.} A liquefier 24 is provided.

The primary refrigerant circuit 12 is provided with a bypass path 26 a that bypasses the compressor 16 and a bypass path 26 b that bypasses the expansion valve 22. The bypass passage 26a is provided with a switching valve 28a that opens and closes in order to switch the flow of the NH ₃ refrigerant to the primary refrigerant circuit 12 or the bypass passage 26a. The bypass path 26b is provided with a switching valve 28b that opens and closes in order to switch the flow of the NH ₃ refrigerant to the primary refrigerant circuit 12 or the bypass path 26b.

In the secondary refrigerant circuit 14, CO ₂ refrigerant is circulated as a secondary refrigerant, and a CO ₂ receiver 30 and a CO ₂ liquid pump 32 that circulates the CO ₂ refrigerant are provided. The CO ₂ liquefier 24 and the CO ₂ receiver 30 are connected by a CO ₂ circulation path 42. The secondary refrigerant circuit 14 is led inside the server room 34 and connected to a plurality of coolers 36 provided inside the server room 34. Inside the server room 34, a large number of server racks 40 in which servers are stored are stacked up and down, arranged in a straight line, and arranged in a plurality of rows in the lateral direction.

The secondary refrigerant circuit 14 is maintained at a high pressure so that the evaporation temperature of the CO ₂ refrigerant is set to normal temperature. For example, in order to set the evaporation temperature of the CO ₂ refrigerant to 22 ° C., it is adjusted to 5.9 MPa.

In such a configuration, in the primary refrigerant circuit 12, NH ₃ refrigerant gas is compressed by the compressor 16, and the NH ₃ refrigerant gas discharged from the compressor 16 is cooled and liquefied by the outside air a in the evaporative condenser 18. The liquefied NH ₃ refrigerant is temporarily stored in the NH ₃ receiver 20. NH ₃ refrigerant liquid once stored in NH ₃ receiver 20 after being reduced by the expansion valve 22, it is CO ₂ refrigerant exchanges heat in a CO ₂ liquefier 24, vaporized by absorbing heat from the CO ₂ refrigerant. The vaporized NH ₃ refrigerant is sent again to the compressor 16 and compressed.

The CO ₂ refrigerant circulating in the secondary refrigerant circuit 14 is temporarily stored in the CO ₂ receiver 30 and separated into gas and liquid. CO ₂ refrigerant gas CO ₂ receiver 30 is sent to the CO ₂ liquefier 24 through the CO ₂ circulation path 42, NH ₃ refrigerant liquid in a CO ₂ liquefier 24 and is heat exchanged. NH ₃ CO ₂ refrigerant is liquefied by heat exchange with the refrigerant liquid is returned to CO ₂ receiver 30 via the CO ₂ circulation path 42.

The CO ₂ refrigerant liquid in the CO ₂ receiver 30 is sent to the cooler 36 via the secondary refrigerant circuit 14. In the cooler 36, the CO ₂ refrigerant liquid exchanges heat with the air in the server room 34, and the air in the server room 34 is cooled by the latent heat of evaporation, and a part thereof is vaporized.

The air in the hot region in which a hot flow hf, which will be described later, is formed in the server chamber 34 is heated to, for example, about 35 ° C. due to heat radiation from the server. The heated air can be cooled to, for example, 25 ° C. with a 22 ° C. CO ₂ refrigerant liquid flowing through the cooler 36 and supplied to a cold region where a cold flow cf described later is formed. The CO ₂ refrigerant that has become a gas-liquid two-phase flow by heat exchange with the air in the server chamber 34 returns to the CO ₂ receiver 30.

  The room air cooled by the cooler 36 forms a cold flow cf that goes downward in the space between the server racks 40 by a blower 38 provided in the cooler 36. In each server rack 40, gaps are formed between the servers, and a number of cold air passages cw into which cooling air flows from the cold flow cf are formed in these gaps. The cooling air cools the server and rises in temperature, and then flows out of the server rack 40. The heated air that has flowed out of the server rack 40 forms a hot flow hf that rises toward the cooler 36.

Next, based on FIGS. 2-6, the configuration of the CO ₂ liquefier 24. The CO ₂ liquefier 24 constitutes a shell and plate heat exchanger, and is incorporated in the primary refrigerant circuit 12 as a full liquid evaporator (cascade condenser). In the CO ₂ liquefier 24, the NH ₃ refrigerant liquid as the primary refrigerant and the CO ₂ refrigerant gas as the secondary refrigerant are heat-exchanged, the NH ₃ refrigerant absorbs heat from the CO ₂ refrigerant and vaporizes, and the CO ₂ refrigerant liquefies. .

2 to 4, a plate polymer 52 is accommodated in a hollow container 50 having a circular cross section and a cylindrical shape. The plate polymer 52 is formed in a cylindrical shape by overlapping a large number of disk-shaped plates 54. An NH ₃ introduction port 56 is formed at one axial end of the upper wall of the hollow container 50, and an NH ₃ introduction pipe 58 is provided at the NH ₃ introduction port 56. An NH ₃ spraying tube 60 is connected to the tip of the NH ₃ introduction tube 58 inside the hollow container 50. The NH ₃ spraying tube 60 is disposed substantially parallel to the upper wall 50 a of the hollow container 50.

As shown in FIG. 4, the NH ₃ spray pipe 60 has a large number of narrow spray holes 60 a formed in two rows in the axial direction downward.

FIG. 5 is an enlarged view of the NH ₃ introduction pipe 58, the NH ₃ spraying pipe 60 and the hollow housing 68. The NH ₃ introduction pipe 58 is connected to the primary refrigerant circuit 12. NH ₃ refrigerant liquid is supplied from the NH ₃ inlet tube 58 to the NH ₃ sparge tube 60. The hollow housing 68 extends in the axial direction of the hollow container 50, and the NH ₃ spraying tube 60 is fixed to the lower surface of the hollow housing 68 by tap welding w. Therefore, the hollow housing 68 and the NH ₃ spraying tube 60 are integrally formed.

On wall end portion of the axially opposite side of the NH ₃ inlet tube 58 and the hollow container 50, NH ₃ outlet 64 is formed, NH ₃ outlet pipe 66 is provided in the NH ₃ outlet 64. The NH ₃ outlet pipe 66 is connected to the primary refrigerant circuit 12. A hollow housing 68 is integrally connected to the lower end of the NH ₃ outlet tube 66.

  As shown in FIG. 4, the cross section of the hollow housing 68 is a quadrangle having a long side 68a in the horizontal direction (that is, a horizontal direction) and a short side 68b in the vertical direction.

FIG. 6 is a top view of a hollow housing 68 according to a reference example of the present invention . As shown in FIG. 6, on the upper surface of the hollow housing 68, a large number of NH ₃ gas introduction holes 68c arranged in two rows in axial symmetry with respect to the longitudinal direction are formed.

2 and 3, a CO ₂ introduction port 70 is formed on one side wall of the hollow container 50, and a CO ₂ introduction pipe 72 is formed on the CO ₂ introduction port 70. The CO ₂ introduction pipe 72 is connected to the CO ₂ circulation path 42, and communicates the CO ₂ introduction pipe 72 and the heat exchange flow path of the CO ₂ refrigerant formed on the front and back surfaces of each plate 54 inside the plate polymer 52. A CO ₂ flow path 74 is formed.

Moreover, CO ₂ outlet 76 is formed in the side wall below the CO ₂ inlet tube 72, CO ₂ discharge pipe 78 to the CO ₂ outlet 76 is formed. The CO ₂ lead-out pipe 78 is connected to the CO ₂ circulation path 42, and communicates the CO ₂ lead-out pipe 78 with the heat exchange flow path of the CO ₂ refrigerant formed on the front and back surfaces of each plate 54 inside the plate polymer 52. A CO ₂ flow path 80 is formed.

A large number of plates 54 constituting the plate polymer 52 have specific uneven patterns on both front and back surfaces, and these plates 54 are alternately stacked. Thereby, two independent flow paths are alternately formed on the front and back surfaces of the plate 54. One flow path opens into the internal space of the hollow container 50, and NH ₃ refrigerant flows from this opening. Each plate 54 is formed with two openings at the same position, and these openings are overlapped to form CO ₂ channels 74 and 80. CO ₂ refrigerant gas flowing from the opening 70 through the CO ₂ flow path 74, flows through the other flow path formed in the front and back surfaces to the plate 54, after NH ₃ refrigerant exchanges heat between the CO ₂ flow path 80 Through the opening 76.

  The structure of the plate polymer 52 of such a shell-and-plate heat exchanger is conventionally known (see, for example, JP 2012-57900 A).

  As shown in FIG. 4, stays 82 a and 82 b are installed between the side wall of the hollow container 50 and the plate polymer 52. A stay 84a that partitions the side wall of the hollow container 50 and the plate polymer 52 is provided below the stay 82a, and a stay 84b that partitions the side wall of the hollow container 50 and the plate polymer 52 is provided below the stay 82b. It has been. The space s1 formed between the stay 82a and the stay 84a is filled with the rod-shaped filler 86, and the space s2 formed between the stay 82b and the stay 84b is filled with the rod-shaped filler 86. Has been.

Heat exchange is performed between the NH ₃ refrigerant liquid and the CO ₂ refrigerant gas in the plate polymer 52, and the NH ₃ refrigerant liquid absorbs heat from the CO ₂ refrigerant and vaporizes. Conversely, the CO ₂ refrigerant gas is cooled and liquefied. The vaporized NH ₃ refrigerant gas rises, flows into the inside of the hollow housing 68 from the NH ₃ gas introduction hole 68c, and flows out from the NH ₃ lead-out pipe 66 to the primary refrigerant circuit 12.

In such a configuration, when the outside air temperature is 20 ° C. (WB 15 ° C./relative humidity 60%) or less, an operation in which the compressor 16 is not operated is performed. That is, the NH ₃ refrigerant circulates between the CO ₂ liquefier 24 and the evaporative condenser 18 through the bypass paths 26a and 26b.

In the CO ₂ liquefier 24, the CO ₂ refrigerant gas exchanges heat with the 20 ° C. NH ₃ refrigerant condensed by exchanging heat with the outside air a in the evaporative condenser 18. By this heat exchange, the NH ₃ refrigerant evaporates, and the CO ₂ refrigerant becomes a CO ₂ liquid at 22 ° C.

  The evaporative condenser 18 is provided with a heat transfer tube 18 a, and the heat transfer tube 18 a is connected to the primary refrigerant circuit 12. The cooling water stored in the evaporative condenser 18 is pumped up by the water pump 18b and dispersed in the heat transfer tube 18a. The NH3 refrigerant gas flowing through the heat transfer pipe 18a by the latent heat of evaporation in this cooling water is cooled and liquefied.

In an operation in which the compressor 16 is not operated, the NH ₃ refrigerant gas vaporized by the CO ₂ liquefier 24 moves up the bypass 26a by a thermosiphon action. The NH ₃ refrigerant liquid liquefied by the evaporative condenser 18 flows down the primary refrigerant circuit 12 and the bypass path 26b by the gravity, and returns to the CO ₂ liquefier 24.

  When the outside air temperature is 20 ° C. (WB 15 ° C./relative humidity 60%) or more, the switching valves 28a and 28b are closed and the compressor 16 is operated.

In the CO ₂ liquefier 24, the CO ₂ refrigerant exchanges heat with the NH ₃ refrigerant liquid to become a 22 ° C. CO ₂ liquid. The 22 ° C. CO ₂ refrigerant liquid is sent to a cooler 36 provided in the server room 34, and the cooler 36 cools the air in the server room 34 to 25 ° C. The room air cooled to 25 ° C. is sent downward by the blower 38 to form a cold flow cf.

  The cooling air passes through the cool air passage cw formed between the server racks 40, cools the information processing equipment, raises the temperature to 35 ° C., and flows out of the server rack 40. Thereafter, a rising hot flow hf is formed. The hot stream hf is cooled to 25 ° C. by the cooler 36.

According to the present embodiment, as the refrigerant, NH ₃ and CO ₂ , which are natural refrigerants that have no ozone depleting action and have a global warming potential close to zero, there is no fear of global warming, and these Since the refrigerant has a high cooling capacity, the cooling efficiency can be improved.

Furthermore, the CO ₂ refrigerant is adjusted to room temperature by maintaining the inside of the secondary refrigerant circuit at a high pressure, and the evaporation temperature of the CO ₂ refrigerant in the cooler 36 is adjusted to be room temperature. Air can be easily cooled to room temperature by the latent heat of vaporization of the CO ₂ refrigerant. In addition, since the normal temperature CO ₂ refrigerant flows through the secondary refrigerant circuit 14, there is no risk of condensation, and even if the CO ₂ refrigerant leaks in the server room 34, it vaporizes and damages information processing equipment. There is no fear.

  Further, since the cold flow cf from the cooler 36 and the hot flow hf from the server rack 40 are formed separately in different regions in the server room 34, these air flows may be mixed. Absent. Therefore, the cooling efficiency of the server room 34 can be improved.

Further, when the outside air temperature is below normal temperature, the operation of the compressor 16 is stopped, and the NH ₃ refrigerant is cooled by the outside air a below normal temperature in the evaporative condenser 18, and the CO ₂ liquefier 24 and the evaporative condenser 18 are cooled. Since the NH ₃ refrigerant is naturally circulated using the thermosiphon action, the power of the compressor 16 can be saved and the COP can be improved.

Further, in the CO ₂ liquefier 24, the hollow housing 68 has a cross section formed in a rectangular shape having long sides 68a that are long in the lateral direction, and thus has an excellent baffle effect. The vaporized NH ₃ refrigerant passes through a bypass channel formed outside the hollow housing 68, so that the droplet separation effect can be improved before reaching the NH ₃ gas introduction hole 68c. Therefore, liquid back to the compressor 16 can be effectively prevented.

Further, since no filter type droplet separator is provided in the flow path of the NH ₃ refrigerant gas, pressure loss can be reduced. Therefore, compressor power can be reduced and COP can be improved.

Further, since the widely be sprayed uniformly and the upper surface of the plate the polymer 52 in the axial direction of the plate polymer _52, NH ₃ refrigerant liquid by NH ₃ sparge tube 60, increase the heat exchange efficiency of the NH ₃ refrigerant and CO ₂ refrigerant it can. Therefore, the amount of NH ₃ refrigerant supplied to the hollow container 50 can be reduced, and the amount of NH ₃ refrigerant flowing through the primary refrigerant circuit 12 can be reduced.

In addition, by filling the spaces s1 and s2 with the filler 86, the amount of NH3 refrigerant supplied to the hollow container 50 can be reduced. In this way, the amount of NH ₃ refrigerant flowing through the primary refrigerant circuit 12 can be greatly reduced, so that the NH ₃ receiver 20 can be reduced in size.

Moreover, the hollow housing 68 does not protrude downward because the cross section of the hollow housing 68 is formed in a rectangular shape having long sides in the horizontal direction. Therefore, the volume of the hollow container 50 can be reduced, and the supply amount of the NH ₃ refrigerant can be reduced correspondingly. Further, since the cross section of the hollow housing 68 is expanded in the lateral direction, the pressure loss of the NH ₃ refrigerant gas passing through the inside of the hollow housing 68 can be reduced, and thereby the power of the compressor 16 can be reduced.

Further, since numerous arranged spraying hole 60a formed in the NH ₃ sparge tube 60 in the axial direction of the NH ₃ sparge tube 60, NH ₃ refrigerant liquid plate polymer 52 uniformly and in the axial direction relative to the plate polymer 52 Can be widely spread on the top surface of Thereby, the heat exchange efficiency between the NH ₃ refrigerant and the CO ₂ refrigerant can be improved.

Furthermore, since the NH ₃ introduction holes 68c are arranged in two rows on the upper surface wall of the hollow housing 68 so as to be axially symmetric with respect to the axial direction of the hollow housing 68, the pressure loss when the NH ₃ refrigerant gas flows into the hollow housing 68 can be reduced. .

Furthermore, since the hollow housing 68 and the NH ₃ spraying tube 60 are integrally formed by tap welding w, it is easy to attach the hollow housing and the coolant spraying tube to the hollow container.

According to the estimation by the present inventors, in the operation in which the compressor 16 was operated, the NH ₃ refrigerant condensation temperature was 35 ° C., the evaporation temperature was 16 ° C., and the outside air temperature was WB + 15 ° C. or more. Operation with a COP of around 6 is possible. Further, in a free cooling operation in which the compressor 16 is not operated, when the outside air temperature is set to WB + 15 ° C. or less, an operation with a COP of 13 or more is possible. When the air conditioning facility 10A of this embodiment is applied to a server room provided in the Tokyo area, the annual free cooling operation day is 200 days or more, and the annual COP is 10 or more.

In the above-described reference example of the present invention, the case where the spaces s1 and s2 are formed between the hollow container 50 and the plate polymer 52 is shown. However, in the embodiment shown in FIG. Spaces s1 and s2 between the polymer 52 are narrowed . In this case, as shown in FIG. 7 (cross-sectional view), the shape of the plate 54 constituting the plate polymer 52 is relative to the horizontal line H passing through the axis S of the hollow container 50 in the axial view of the hollow container 50. It is formed asymmetric in the vertical direction. That is, the plate 54 a below the axis O of the hollow container 50 has a radius of curvature centered on the position S below the axis O of the hollow container 50 and is close to the inner wall surface 50 b of the hollow container 50. And is formed in a semicircular shape. Further, the plate 50b above the axis O of the hollow container 50 is formed in a flat shape (semi-elliptical shape) having a radius of curvature larger than the radius of curvature around the axis 0 of the hollow container 50. . In the space 50c above the plate polymer 52, an NH ₃ introduction pipe 60 and a hollow housing 68 are disposed. Since these have been described above, description thereof will be omitted.

Thus, by reducing the gaps s1 and s2 between the outer periphery of the plate 54 and the inner wall surface 50b of the hollow container 50, the hollow container 50 can be reduced in size. Therefore, it is not necessary to fill the gap between the outer periphery of the plate 54 and the inner wall surface 50b of the hollow container 50, and the manufacturing cost of the CO ₂ liquefier 24 (refrigerant heat exchanger) is coupled with the downsizing of the hollow container 50. Can be reduced.

According to the present invention, the spaces s1 and s2 between the hollow container and the plate polymer can be narrowed. Thus, the hollow container can be reduced in size by reducing the gaps s1 and s2 between the outer periphery of the plate and the inner wall surface b of the hollow container. Therefore, coupled with the downsizing of the hollow container, the manufacturing cost of the refrigerant heat exchanger can be reduced.

DESCRIPTION OF SYMBOLS 10 Air conditioning equipment 12 Primary refrigerant circuit 14 Secondary refrigerant circuit 16 Compressor 18 Evaporative condenser 20 NH ₃ receiver 22 Expansion valve 24 CO ₂ liquefier (refrigerant heat exchanger)
26a, 26b Bypass path 28a, 28b Switching valve 30 CO ₂ receiver 34 Server room 36 Cooler 38 Blower 40 Server rack 42 CO ₂ circulation path 50 Hollow container 50a Upper wall 50b Inner wall surface 50c Space portion 52 Plate polymer 54 Plate 54a Plate Lower side 54b Upper part of plate 56 NH ₃ inlet 58 NH ₃ inlet pipe (first inlet)
60 NH ₃ spray pipe 60a spray hole 64 NH ₃ outlet (first outlet)
66 NH ₃ outlet pipe (refrigerant gas outlet pipe)
68 Hollow housing 68a Long side 68b Short side 68c NH ₃ introduction hole (refrigerant gas introduction hole)
70 CO ₂ inlet (second inlet)
72 CO ₂ introduction pipe 74 CO ₂ passage (refrigerant introduction passage)
76 CO ₂ outlet (second outlet)
78 CO ₂ outlet pipe 80 CO ₂ passage (refrigerant outlet passage)
82a, 82b, 84a, 84b Stay 86 Filling material a Outside air cf Cold flow cw Cold air passage hf Hot flow s1, s2 Space

Claims (2)

A first inlet through which the first refrigerant is introduced, a first outlet through which the first refrigerant vaporized therein is led out, a second inlet through which the second refrigerant is introduced, and a second A cylindrical hollow container in which a second outlet from which the refrigerant is led out is formed;
A plate polymer that is arranged inside the hollow container and on which front and back surfaces are stacked with a large number of plates on which concavities and convexities that form heat exchange channels for the first refrigerant and the second refrigerant are formed;
A hollow housing having a refrigerant gas introduction pipe connected to the first outlet and a refrigerant gas introduction hole formed in an upper surface wall of the upper space of the plate polymer so as to face the upper partition wall of the hollow container;
A refrigerant introduction path connecting the second inlet and the heat exchange flow path of the second refrigerant, and a refrigerant outlet path connecting the heat exchange flow path of the second refrigerant and the second outlet. Prepared,
The upper wall of the hollow housing is disposed in close proximity to the inner surface of the upper partition wall and extends in the axial direction of the cylindrical hollow container,
The refrigerant gas introduction hole is a refrigerant heat exchanger provided in the upper surface wall with a plurality of intervals in the axial direction of the cylindrical hollow container ,
The plate constituting the plate polymer has a radius of curvature centered on a position (S) below the axis (O) of the hollow container, with the plate below the axis (O) of the hollow container. And is formed in a semicircular shape along the vicinity of the inner wall surface of the hollow container, and the plate above the axis (O) of the hollow container is centered on the axis (0) of the hollow container A refrigerant heat exchanger characterized by being formed in a semi-elliptical shape having a radius of curvature larger than the radius of curvature . The hollow housing extending in the axial direction in the cylindrical hollow container while being opposed to the upper partition wall of the hollow container;
A refrigerant distribution pipe connected to the first introduction port and provided on the lower surface of the hollow housing in the longitudinal direction of the hollow housing and having a distribution hole for distributing the first refrigerant to the plate polymer; The refrigerant heat exchanger according to claim 1, further comprising:

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