JP5202666B2 - Refrigeration system - Google Patents

Description

  The present invention relates to a refrigerant liquid forced circulation type refrigeration system, and more particularly to a refrigerant liquid forced circulation type refrigeration system including a heat exchanger provided with a plurality of divisional cooling coil systems.

  Generally, a heat exchanger of a refrigerant liquid forced circulation refrigeration system is connected to a plurality of cooling coils arranged in parallel to each other, a large number of heat transfer fins in contact with each cooling coil, and one end of each cooling coil. A header type flow divider, and the refrigerant liquid flowing into the flow divider from the refrigerant liquid pump is divided into each cooling coil, and heat exchange between the refrigerant liquid flowing through each cooling coil and external air is performed. What is performed via the heat transfer fin is known (for example, refer to Patent Document 1).

  Conventionally, a cooling coil provided with a plurality of refrigerant passages is arranged vertically or horizontally or front and back, and one of the cooling coils arranged vertically or horizontally or front and rear, that is, upper side or lower side, left side or right side, front side Alternatively, a method is known in which only the rear side is operated, or both are operated at the same time, and the temperature control is performed by dividing the cooling coil into a divided state.

  Here, in the control of the cooling coil in the conventional refrigeration system, the control is performed for each cooling coil. Moreover, the refrigerant coil is installed for each refrigerant coil. Therefore, when each cooling coil is arranged vertically, for example, when one cooling coil arranged on the upper side or the lower side is stopped, only one cooling coil arranged on the upper side or the lower side is stopped. It will be cooled with. For this reason, since the operation is performed only with the cooling coils arranged on the upper side or the lower side of the heat exchanger, if the load is small, the refrigerant flow is biased and temperature unevenness occurs in the outlet air, and the evaporation temperature As a result, the capacity is reduced. Further, the lower or upper cooling coil that is not stopped may be operated while complementing the amount of the stopped cooling coil. In this case, the operation may exceed the capacity, and a sufficient driving ability cannot be obtained. This is the same also when each cooling coil is arrange | positioned at right and left, for example.

  Furthermore, when each cooling coil is disposed, for example, in the front-rear direction, that is, in the direction in which heat-exchanged air flows, when the front cooling coil disposed on the upstream side is stopped, the rear cooling coil is liquid. May cause back.

JP2001-133308A. JP-A-7-280338.

As described above, the control of the cooling coil in the conventional refrigeration system is arranged for each cooling coil and is controlled for each cooling coil. Therefore, when the cooling coils are arranged vertically or horizontally In this case, when only one cooling coil is operated on the upper side or the lower side, or when only one cooling coil is operated on the left side or the right side, temperature unevenness occurs and the performance is reduced. Further, when the cooling coils are arranged at the front and rear, and only the rear cooling coil is operated, the rear cooling coil is in the liquid back operation. Therefore, when these problems are taken into consideration, there is a problem that energy-saving operation by unit control is difficult.

  Therefore, by arranging the refrigerant flow passages in the multiple cooling coil systems in consideration of the temperature distribution, the temperature unevenness of the outlet air can be eliminated, the capacity reduction of the refrigerator can be suppressed, and energy-saving operation can be performed. The technical problem which should be solved in order to provide the refrigerant | coolant liquid forced circulation type refrigeration system made arises, and this invention aims at solving this problem.

The present invention has been proposed to achieve the above object, and the invention according to claim 1 is a heat exchange having a refrigerant compressor, a condenser, an expansion valve, a low-pressure receiver, and a cooling coil. And a refrigeration cycle including a refrigerant liquid pump for supplying a refrigerant liquid to the heat exchanger to form a refrigeration or heat pump cycle, and the cooling coil meanders by alternately providing straight and curved portions parallel to each other. In the refrigerant liquid forced circulation refrigeration system having a plurality of cooling coil systems having a plurality of refrigerant flow passages formed in a shape, the plurality of cooling coil systems are located upstream of the heat exchanger. Each of the cooling coil systems is provided in each of a plurality of paths branched from the refrigerant pipe, and the refrigerant flow passages of the cooling coil systems are alternately shifted in a direction perpendicular to the air flow to be heat-exchanged. Before the system It will be arranged by shifting the flow direction of the air from each other straight portions by a predetermined pitch minutes, and a controllable control valve is independent of the flow rate of the coolant for the cooling coil system respectively to the respective cooling coil system A refrigerant liquid forcing is provided, wherein a distributor for evenly distributing the refrigerant from the refrigerant liquid pump to each refrigerant flow passage is connected to the inlet side of the refrigerant flow passage of each cooling coil system A circulating refrigeration system is provided.

According to this configuration, the refrigerant flow passages of the respective cooling coil systems are alternately arranged with respect to the flow direction of the air to be heat-exchanged, and the straight portions are arranged to be shifted from each other by a predetermined pitch in the flow direction of the air. Thus, the refrigerant flow passages are arranged almost uniformly in the entire passage through which the air for heat exchange flows. As a result, even when the cooling coil systems are switched and operated, it is possible to minimize the occurrence of temperature unevenness that the temperature of the air near the outlet varies depending on the location. Control is also possible. In addition, the refrigerant supplied to each refrigerant passage of each cooling coil system is uniformly distributed by the distributor.

The invention according to claim 2 provides the refrigerant liquid forced circulation type refrigeration system according to claim 1, wherein each cooling coil system and the distributor are connected via a capillary tube. .

According to this configuration, the refrigerant supplied to each refrigerant passage of the cooling coil system can be divided and supplied uniformly by the distributor and the capillary tube.

The invention according to claim 3 is characterized in that an annular space portion is formed in the distributor by providing a protrusion portion against which the refrigerant flowing into the distributor collides. A refrigerant liquid forced circulation refrigeration system is provided.

According to this configuration, since the refrigerant once hits the protrusion inside the distributor, the influence of the drift of the refrigerant is canceled out, so that each refrigerant flowing out from the refrigerant outlet can be evenly divided.

The invention of claim 4, wherein, in the structure of the 請 Motomeko 1, wherein, provided the control valve for each of the cooling coil system, so that it can be controlled independently is allowed the flow of the refrigerant in each of the cooling coil A refrigerant liquid forced circulation refrigeration system is provided.

According to this configuration, since the refrigerant flow can be controlled independently for each cooling coil system, the refrigerant flow in each cooling coil system can be more finely controlled.

According to the first aspect of the present invention, the temperature distribution is taken into consideration for each cooling coil system, and the refrigerant flow passages of the respective cooling coil systems are arranged almost uniformly distributed in the entire passage through which the air for heat exchange flows. In addition, since the refrigerant flow passages of the respective cooling coil systems are provided in the passages through which the heat exchange air flows, it is possible to minimize the occurrence of temperature unevenness in which the air temperature near the outlet varies depending on the location. it can. Thereby, the refrigerating capacity can be improved. In addition, when the load is low, control for stopping each cooling coil system, that is, control of the number of units can be performed, which can contribute to energy saving. It is also possible to control the flow rate with a control valve for each cooling system. Further, the distributor can prevent the refrigerant from diverting to the respective cooling coil systems at an unintended ratio. As a result, the temperature unevenness at each air outlet is further eliminated, and the refrigerating capacity can be improved by eliminating the occurrence of gas locks in each cooling coil system and the accumulation of refrigerating machine oil.

In the invention according to claim 2 , by supplying the refrigerant flowing out from the refrigerant outlet of the distributor into the refrigerant passage on the cooling coil system side through the capillary tube, the pressure of the refrigerant is made more uniform by this caterpillar tube. Therefore, in addition to the effect of the invention of claim 1, it is possible to further prevent the refrigerant from being diverted at an unintended ratio.

In the invention described in claim 3, since the refrigerant flowing into the distributor once strikes the protrusion, the influence of the drift of the refrigerant can be counteracted. Therefore, in addition to the effect of the invention described in claim 1 or 2, The refrigerant flowing out from the outlet can be more evenly divided.

  In the invention according to claim 4, since the invention according to claim 4 can control the refrigerant flow independently for each cooling coil system, in addition to the effect of the invention according to claim 1, 2 or 3 , Control can be performed more finely and contribute to energy saving.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows the Example of the refrigerant liquid forced circulation type refrigeration system to which this invention is applied. The schematic diagram which shows one example of arrangement | positioning of the cooling coil system in a refrigerant liquid forced circulation type refrigerating system same as the above with a distributor. The connection diagram explaining the connection structure of the cooling coil system and distributor in the same refrigerant liquid forced circulation type refrigeration system shown in FIG. The side view of the distributor in a refrigerant liquid forced circulation type refrigerating system same as the above. AA sectional drawing of FIG. The schematic diagram explaining the modification of the cooling coil in a refrigerant liquid forced circulation type refrigerating system same as the above. The connection diagram explaining the connection structure of the cooling coil and distributor in the same refrigerant liquid forced circulation type refrigeration system shown in FIG.

The present invention eliminates the temperature unevenness of the outlet air and reduces the capacity of the refrigerator by arranging the plurality of cooling coil systems in the arrangement of the refrigerant flow passages in the plurality of cooling coil systems in consideration of the temperature distribution. In order to achieve the purpose of providing a refrigerant liquid forced circulation type refrigeration system that can suppress energy consumption and enable energy saving operation, a refrigerant compressor, a condenser, an expansion valve, a low-pressure receiver, and a cooling coil are provided. A refrigeration cycle including a heat exchanger having a refrigerant temperature and a refrigerant liquid pump that supplies a refrigerant liquid to the heat exchanger forms a refrigeration or heat pump cycle, and the cooling coil alternates between straight and curved portions parallel to each other. comprising a plurality of refrigerant flow paths form a serpentine shape provided at a plurality of refrigerant liquid forced circulation refrigerating system with a cooling coil system, said plurality of cooling coil system, the heat exchanger Respectively provided in each path branched into a plurality of the refrigerant pipe on the upstream side, the said respective refrigerant flow paths of the cooling coil system, together with the shifted respectively staggered in the direction perpendicular to the flow of air to the heat exchanger, the result was arranged by shifting by a predetermined pitch minutes the linear portion in the flow direction of the air from each other in the cooling coil system and said controllable control valve is independent of the flow rate of the coolant for the cooling coil system This is realized by providing each cooling coil system with a distributor for equally distributing the refrigerant to each refrigerant flow passage on the inlet side of the refrigerant flow passage of each cooling coil system .

  Hereinafter, a preferred example of a refrigerant liquid forced circulation type refrigeration system according to an embodiment of the present invention will be described based on the drawings as a case where it is applied to an environmental test apparatus for performing an environmental test of an automobile indoors.

  FIG. 1 is a schematic configuration diagram showing a refrigerant liquid forced circulation refrigeration system according to the present invention. In the figure, the refrigeration system 10 has a circulating refrigerant circuit including a refrigerant compressor 11, a condenser 12, a high-pressure receiver 13, an expansion valve 14, a low-pressure receiver 15, an evaporator 16, and the like. Yes.

  More specifically, in the refrigerant pipe 17a connecting the evaporator 16 and the low-pressure receiver 15, the refrigerant liquid in the low-pressure receiver 15 is distributed to the cooling coil 16a in the evaporator 16 to the distributor 18. There is provided a refrigerant liquid pump 19 that is supplied via the. Further, the refrigerant heat-exchanged by the cooling coil 16a in the evaporator 16 is returned to the low-pressure receiver 15 through the header 25 and the refrigerant pipe 17b. Two or more refrigerant compressors 11 are provided.

  The refrigerant pipe 17c that connects the low-pressure receiver 15 and the refrigerant compressor 11 is provided with a regulating valve 20, and connects the high-pressure receiver 13 and the low-pressure receiver 15. An electromagnetic valve 21 and the expansion valve 14 are provided in the refrigerant pipe 17f. The low-pressure receiver 15 and the high-pressure receiver 13 are provided with liquid level sensors 22 and 23 for detecting the amount of refrigerant liquid in the low-pressure receiver 15 and the high-pressure receiver 13, respectively. It has been.

  As shown in FIGS. 2 and 3, the cooling coil 16a of the evaporator 16 includes two cooling coil systems, a first cooling coil system 36a and a second cooling coil system 36b. Each of the cooling coil systems 36a and 36b is formed by bending a copper or aluminum tube in a meandering manner by alternately providing linear portions 37 and curved portions 38 which are parallel to each other, so that the refrigerant flows through the inside thereof. The four refrigerant flow passages 39a, 39b, 39c, and 39d are formed. Further, a large number of heat transfer fins (not shown) in contact with the tubes are attached to the tubes forming the refrigerant flow passages 39a, 39b, 39c, and 39d.

  The refrigerant flow passages 39a to 39d of the first cooling coil system 36a and the refrigerant flow passages 39a to 39d of the second cooling coil 36b are temperature distributions when the operation is stopped for each of the cooling coil systems 36a and 36b. In consideration of the above, the cooling coil systems 36a and 36b are arranged in order in the flow direction diagram of the air to be heat-exchanged by alternately shifting them at equal intervals in the direction orthogonal to the direction indicated by the arrow 29. In this example, the refrigerant flow passages 39a to 39d are parallel to the air flow direction 29 for exchanging heat, and the linear portions 37 of the cooling coil systems 36a and 36b are arranged in the air flow direction 29 with a predetermined pitch. They are shifted by 2/3 pitches. Therefore, in the evaporator 16, the refrigerant flow passages 39a to 39d of the cooling coil systems 36a and 36b are arranged substantially uniformly with respect to the entire passage through which the heat exchange air flows. .

Further, the distributors 18 and 18 and the control are respectively connected to the refrigerant input sides of the refrigerant flow passages 39a to 39d of the first cooling coil system 36a and the second cooling coil system 36b via capillary tubes 27, 27. The valves 40 and 40 are connected, and the headers 25 and 25 connected to the low-pressure receiver 15 are connected to the refrigerant output side via the refrigerant pipe 17b.

  As shown in FIGS. 4 and 5, the distributor 18 is provided with one refrigerant inlet 18a on one end side and a plurality of refrigerant outlets 18b, 18b... In this example on the other end side. . Further, the distributor 18 is formed in an annular shape by providing a conical protrusion 18c protruding from the refrigerant outflow side into the refrigerant inlet 18a at a portion facing the refrigerant inlet 18a. A space portion 28 is formed. The refrigerant outlets 18b, 18b,... Are provided at substantially equal intervals on the refrigerant outflow side of the space portion 28, and one ends of the capillary tubes 27, 27 ... are connected to the refrigerant outlets 18b, 18b, respectively. .

  The capillary tubes 27, 27... Are copper capillaries having an inner diameter of about 0.7 to 2.5 mm, and the other end sides are respectively refrigerant passages 39a, 39b, 39c, 39d in the cooling coil systems 36a, 36b. Connected to the refrigerant inlet.

  Therefore, in the distributor 18 configured in this way, the refrigerant that has flowed into the space 27 from the refrigerant inflow port 18a once hits the conical protrusion 18c, and the protrusion 18c causes the refrigerant to flow. The effect of current drift is negated. Then, by canceling the influence of this drift, the refrigerant flowing out from the refrigerant outlets 18b, 18b,... Can be evenly divided. The shape of the space 27 may not be a shape provided with the conical protrusion 18c as long as the influence of the drift of the refrigerant can be canceled.

  Further, the cooling coils 16a, 16a,... Are not directly connected to the refrigerant outlets 18b, 18b,... Of the distributor 18, so that the refrigerant is supplied to the cooling coil 26 side through the capillary tube 27. Therefore, the distribution of the refrigerant flowing out from the refrigerant outlets 18b, 18b... Of the distributor 18 and flowing into the cooling coils 16a, 16a.

  Next, the overall operation of the refrigeration system 10 configured as described above will be described with reference to FIG. First, the refrigerant liquid discharged from the high-pressure receiver 13 to the refrigerant pipe 17 f is vaporized under reduced pressure by the expansion valve 14 and introduced into the low-pressure receiver 15 from above.

  Further, the vaporized refrigerant in the low-pressure receiver 15 is sucked into the compressor 11 via the regulating valve 20 and compressed. The compressed gas is sent to the condenser 12 through the refrigerant pipe 17d, and heat is exchanged with the cooling water 24 in the condenser 12 to condense and liquefy, and change from a gas state to a liquid state.

  The refrigerant liquid liquefied in the condenser 12 is introduced into the high-pressure liquid receiver 13 from above through the refrigerant pipe 17e.

  On the other hand, when the refrigerant liquid pump 19 is driven, the evaporator 16 is supplied with a low-pressure refrigerant liquid from the low-pressure receiver 15 via the refrigerant pipe 17a, and this refrigerant liquid is controlled by the control. The refrigerant flow passages 39a, 39b, 39c, 39d of the first cooling coil system 36a and the refrigerant flow of the second cooling coil system 36b through the valves 40, 40, the distributors 18, 18 and the capillary tubes 27, 27. The channels 39a, 39b, 39c, 39d... Are equally distributed and supplied.

The refrigerant liquid is evaporated when it passes through the first cooling coil system 36a and the second cooling coil system 36b in the evaporator 16, and the heat of vaporization passes through the evaporator 16 with the heat of vaporization. Cool the air flowing into the. Further, the refrigerant gas that has changed from the liquid state to the gas state in the evaporator 16 and contributed to cooling is introduced from the top into the low-pressure liquid receiver 15 from the headers 25 and 25 through the refrigerant pipe 17b. Is done.

  Therefore, in the refrigeration system according to this embodiment, the above operation is repeated as necessary, so that the evaporator 16 and the condenser 12 have a predetermined temperature, for example, in the range of −50 ° C. to 50 ° C. Temperature control can be performed with one liquid refrigerant.

  When energy saving control is performed, the control valves 40 and 40 are closed to stop the refrigerant flowing through the first cooling coil system 36a or the second cooling coil system 36b. In this case, in the evaporator 16, the refrigerant flow passages 39a to 39d of the first cooling coil system 36a and the second cooling coil 36b are considered in consideration of the temperature distribution when the operation is stopped for each of the cooling coil systems 36a and 36b. The refrigerant flow passages 39a to 39d are alternately arranged at equal intervals in the direction orthogonal to the flow direction 29 of the air to be heat-exchanged, and the refrigerant flow passages 39a of the cooling coil systems 36a and 36b. -39d are parallel to the air flow direction 29 for exchanging heat, and the linear portions 37 of the cooling coil systems 36a and 36b are shifted from each other by a predetermined pitch in the air flow direction 29. Yes. With this arrangement, the refrigerant flow passages 39a to 39d of the cooling coil systems 36a and 36b are substantially uniform with respect to the entire passage through which air for heat exchange flows, in particular, the inside of the passage through which air flows is viewed from the front side. In this case, since it is in a state of being arranged almost uniformly over the entire surface, it is possible to minimize the occurrence of temperature unevenness such that the temperature of the air near the outlet varies from place to place. Thereby, temperature nonuniformity is eliminated and the refrigeration capacity can be improved. Further, control for each cooling coil system, that is, control of the number of units becomes possible, which can contribute to energy saving.

  6 and 7 show modifications of the cooling coil 16a of the evaporator 16. FIG. In this modification, the cooling coil 16a shown in FIGS. 2 and 3 is composed of two cooling coil systems, a first cooling coil system 36a and a second cooling coil system 36b. The cooling coil system 36a, the second cooling coil system 36b, and the third cooling system coil 36c are configured by three cooling coil systems, and the other configurations are the same as those of the cooling coil 16a shown in FIGS. is there. Accordingly, members corresponding to those in the embodiment shown in FIGS. 1 to 5 are denoted by the same reference numerals as those in FIGS.

  6 and 7, each cooling coil system 36a, 36b, 36c of the cooling coil system 16a is bent in a meandering manner by alternately providing a straight portion 37 and a curved portion 38 parallel to each other of tubes made of copper or aluminum. The refrigerant flow passages 39a, 39b, and 39c are formed so that the refrigerant flows through the inside. In addition, a large number of heat transfer fins (not shown) in contact with the tubes are attached to the tubes forming the refrigerant flow passages 39a, 39b, and 39c.

  The refrigerant flow passages 39a to 39c of the first cooling coil system 36a, the refrigerant flow passages 39a to 39c of the second cooling coil 36b, and the refrigerant flow passages 39a to 39c of the third cooling coil 36c are also shown in FIGS. As in the structure of the above-described embodiment shown in FIG. 5, the temperature distribution when the operation is stopped for each of the cooling coil systems 36a, 36b, 36c is taken into consideration, in a direction orthogonal to the air flow direction 29 for heat exchange. Each of the cooling coil systems 36a, 36b, 36c is parallel to the air flow direction 29 in which heat is exchanged between the refrigerant flow passages 39a to 39c. The linear portions 37 of the cooling coil systems 36a, 36b, 36c are arranged so as to be shifted from each other in the air flow direction 29 by a predetermined pitch by a third pitch in this example. Therefore, even in the evaporator 16, the refrigerant flow passages 39a to 39c of the cooling coil systems 36a, 36b, and 36c are substantially uniform with respect to the entire surface through which heat exchanged air flows, in particular, the passage through which air flows. When the inside is viewed from the front side, it is in a state of being arranged almost uniformly over the entire surface.

  Further, the refrigerant input sides of the refrigerant flow passages 39a to 39c of the first cooling coil system 36a, the second cooling coil system 36b, and the third cooling coil system 36c are respectively connected via capillary tubes 27, 27. The distributors 18, 18, and 18 are connected, and the headers 25 and 25 connected to the low-pressure receiver 15 are connected to the refrigerant output side via the refrigerant pipe 17b.

  Therefore, when the cooling coil 16a structure of this modification is used and the coolant flowing through the first cooling coil system 36a, the second cooling coil system 36b, or the third cooling coil system 36c is stopped, Since the refrigerant flow passages 39a to 39c of the cooling coil systems 36a, 36b, and 36c are substantially uniformly arranged over the entire surface through which the heat exchange air flows, the temperature of the air near the outlet It is possible to minimize the occurrence of temperature unevenness that varies depending on the location. In this modification, the case where there are three cooling coil systems has been described. However, the case where there are four or more cooling coil systems can be similarly configured, and the same effect can be obtained.

  It should be noted that the present invention can be modified in various ways without departing from the spirit of the present invention, and the present invention naturally extends to the modified ones.

  As described above, the present invention is not limited to the air conditioning of the air-conditioned room in the environmental test apparatus, and can be applied to a general refrigeration system.

DESCRIPTION OF SYMBOLS 10 Refrigeration system 11 Refrigerant compressor 12 Condenser 13 High pressure receiver 14 Expansion valve 15 Low pressure receiver 16 Evaporator 16a Cooling coil 17a Refrigerant piping 17b Refrigerant piping 17c Refrigerant piping 17e Refrigerant piping 18 Distributor 27 Capillary tube 28 Space 29 Heat exchange air flow direction 36a First cooling coil system 36b Second cooling coil system 37 Linear portion 38 Curved portions 39a to 39d Refrigerant flow passage 40 Control valve

Claims (4)

The refrigeration cycle includes a refrigerant compressor, a condenser, an expansion valve, a low-pressure receiver, a heat exchanger having a cooling coil, and a refrigerant liquid pump that supplies the refrigerant liquid to the heat exchanger. Forming a heat pump cycle ,
In the refrigerant liquid forced circulation refrigeration system, the cooling coil includes a plurality of cooling coil systems having a plurality of meandering refrigerant passages provided alternately with straight and curved portions parallel to each other . ,
The plurality of cooling coil systems are respectively provided in each path branched into a plurality of pipes from the refrigerant pipe on the upstream side of the heat exchanger,
The refrigerant flow passages of the cooling coil systems are staggered in a direction orthogonal to the air flow to be heat-exchanged, and the linear portions of the cooling coil systems are mutually spaced by a predetermined pitch in the air flow direction. Each of the cooling coil systems is provided with a control valve that is arranged so as to be shifted by minutes and that can be controlled independently of the flow rate of the refrigerant to the cooling coil system
A refrigerant liquid forced circulation system characterized in that a distributor that evenly distributes the refrigerant from the refrigerant liquid pump to each refrigerant flow path is connected to the inlet side of the refrigerant flow path of each cooling coil system. Refrigeration system. The refrigerant liquid forced circulation type refrigeration system according to claim 1, wherein each cooling coil system and the distributor are connected via a capillary tube. The refrigerant liquid forced circulation type refrigeration system according to claim 1 or 2, wherein an annular space portion is formed in the distributor by providing a protruding portion against which the refrigerant flowing into the distributor collides . 4. The refrigerant liquid forced circulation type according to claim 1, wherein the control valve is provided for each cooling coil system so that the flow of the refrigerant can be controlled independently for each cooling coil. Refrigeration system.

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