JP2570914B2 - Cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device, and more particularly to a cooling device having a cooling tower and a plurality of refrigeration cycles.

[0002]

2. Description of the Related Art A cooling apparatus having a cooling tower and a refrigeration cycle is disclosed, for example, in Japanese Utility Model Laid-Open Publication No. 61-84480, which is a technique for a single refrigeration cycle. However, when the load fluctuation of the cooling device is large, a single refrigeration cycle cannot cope with it, and it becomes necessary to use a plurality of refrigeration cycles. Although there is no document that discloses a cooling device having a cooling tower and a plurality of refrigeration cycles, a configuration in which, for example, refrigeration cycles are simply arranged in parallel or simply in series can be easily considered.

[0003]

First, a general problem when a plurality of, for example, four refrigeration cycles A, B, C and D are simply arranged in parallel will be described. Assuming that Q (m ³ / min) is constant and the fluid to be cooled is divided into four and cooled by four refrigeration cycles A, B, C and D, each refrigeration cycle is Q / 4 (m ³ / min).
min), the fluid to be cooled is cooled by 8 ° C., and the refrigeration cycle cools the outlet temperature of the fluid to be cooled at 24 ° C.

When the temperature of the fluid W to be cooled entering the refrigeration cycle is 32 ° C., the necessary cooling capacity can be obtained by operating all four refrigeration cycles as shown in FIG. The temperatures of the fluid to be cooled and the fluid to be cooled are 32 ° C. and 24 ° C., respectively, that is, the average temperature on the inlet side and the outlet side of the fluid to be cooled is 28 ° C. Next, when the temperature of the fluid to be cooled W entering the refrigeration cycle is reduced to 28 ° C. as shown in FIG. 11, the required cooling capacity can be obtained by operating two units, for example, refrigeration cycles C and D. The temperatures of the cooled fluid entering and exiting C and D are 28 ° C. and 20 ° C., respectively. That is, when the inlet temperature of the fluid to be cooled decreases by 4 ° C., the average temperature of the fluid to be cooled in the refrigeration cycles C and D during operation also decreases by 4 ° C. to 24 ° C. On the other hand, the temperatures of the cooled fluid entering and leaving the refrigeration cycles A and B remain at 28 ° C., and the cooled fluid and the cooled fluid at 20 ° C. exiting from the refrigeration cycles C and D remain. By mixing, a fluid to be cooled at 24 ° C. is obtained.

However, as the average temperature of the fluid to be cooled decreases, the cooling capacity decreases. That is, in the refrigeration cycles C and D operating at a low load, the cooling fluid is cooled to a temperature lower than the required outlet temperature of 24 ° C. Since cooling is performed, the cooling efficiency naturally deteriorates. Therefore, in a configuration in which the refrigeration cycles are simply arranged in parallel, the load between the operating refrigeration cycles is uniform, but the individual refrigeration cycles have a problem that the cooling efficiency at low load deteriorates. .

Therefore, as shown in FIG. 12, Q (m ³ / m
In), considering a configuration in which four refrigeration cycles A, B, C, and D capable of cooling the fluid to be cooled by 2 ° C. are arranged in series, when the temperature of the fluid to be cooled W entering the refrigeration cycle is 32 ° C. The required cooling capacity can be obtained by operating all four refrigeration cycles, that is, the average temperatures of the fluids to be cooled in the refrigeration cycles A, B, C and D are 31 ° C. and 29 ° C., respectively.
° C, 27 ° C and 25 ° C. Next, as shown in FIG. 13, when the temperature of the fluid W to be cooled entering the refrigeration cycle has dropped to 28 ° C., the required cooling capacity can be obtained by operating the refrigeration cycles C and D. The average temperature of the cooling fluid remains at 27 ° C and 25 ° C. That is, in the configuration in which the refrigeration cycles are simply arranged in series, the cooling efficiency does not deteriorate even at a low load when looking at the individual refrigeration cycles. There is a problem that the load between them is not uniform.

Accordingly, the present invention provides a cooling device that makes the load between operating refrigeration cycles uniform and that minimizes the deterioration of the cooling efficiency when the load is low even for each refrigeration cycle. The purpose is to:

[0008]

According to the present invention, there are provided a plurality of refrigeration cycles each of which passes a refrigerant in the order of a compressor, a condenser, an expansion valve and an evaporator, and then returns to the compressor. A water spray device for spraying water to the heat radiation pipe and each condenser, and a cooling tower having a fan for blowing air to the heat radiation pipe and each condenser, a plurality of evaporators are provided for each refrigeration cycle, Alternatively, the passage through which the fluid to be cooled of each evaporator passes is divided into a plurality of rooms, and after the fluid to be cooled is passed through the radiating pipe of the cooling tower, a part of the plurality of evaporators of each refrigeration cycle is provided. Or passing a part of the plurality of rooms of each evaporator, and passing the other parts of the plurality of evaporators of each refrigeration cycle in the reverse order of the refrigeration cycle passed. Or through other parts of multiple rooms By, in which to achieve the above objects.

[0009]

Each refrigeration cycle has a set of an evaporator or a room for cooling a relatively high temperature fluid to be cooled and an evaporator or a room for cooling a relatively low temperature fluid to be cooled. The average temperature of the fluid to be cooled between each other is balanced, so that the load is substantially balanced. In any load condition, each evaporator of each refrigeration cycle
Since the cooling target fluid is not cooled below the temperature of the cooling target fluid at the cooling device outlet, the decrease in the cooling efficiency at a low load is minimized.

[0010]

[First Embodiment] The present invention will be described with reference to the drawings. FIG. 1 is a system diagram showing a first embodiment of the present invention. This cooling device comprises four refrigeration cycles A, B, C and D and one cooling tower 50.

The refrigerating cycle A includes a compressor 11 and a condenser 1
2, the high temperature side expansion valve 13, the low temperature side expansion valve 14, the high temperature side evaporator A1 and the low temperature side evaporator A2. In this embodiment, the high temperature side expansion valve 13 and the low temperature side expansion valve 14 are shown in FIG. As described above, each is constituted by a high-temperature side capillary tube and a low-temperature side capillary tube. The piping configuration is such that the refrigerant passes through the compressor 11 and the condenser 12 in this order and then branches, one passes through the high temperature side expansion valve 13 and the high temperature side evaporator A1 tube side, and the other passes through the low temperature side expansion valve 14. Then, the refrigerant is passed in the order of the low-temperature side evaporator A2 tube side, and then the two refrigerants are combined and returned to the compressor 11.

The refrigerating cycles B, C and D are constructed in the same manner as the refrigerating cycle A, but differ slightly in the number of capillary tubes constituting the expansion valve, which will be described later.

The cooling tower 50 includes a radiating pipe 51, and the radiating pipe 51 and the condensers 12, 22, and
A water sprinkling device for spraying water to the cooling water 32 and 42, a fan 55 for blowing air to the condensers 12, 22, 32 and 42 of each refrigeration cycle, and a fan 55
6 is rotationally driven. The water sprinkling device includes a water sprinkling section 60 provided above the heat radiating pipe 51 and a heat radiating pipe 5.
1 includes a water reservoir 61 provided below the water reservoir 61, a water receiving tank 62 for collecting water in the water reservoir 61, a pump 63 and a pipe 64 for supplying water in the water receiving tank 62 to the water sprinkling section 60.

On the other hand, the fluid to be cooled flows into the present cooling device from the inlet pipe 1 and is pressurized by the booster pump 2, after which the heat radiation pipe 51 and the high-temperature side evaporator A of the refrigeration cycle A are used.
1 shell side, high temperature side evaporator B1 shell side of refrigeration cycle B, high temperature side evaporator C1 shell side of refrigeration cycle C, high temperature side evaporator D1 shell side of refrigeration cycle D, low temperature side evaporator D2 shell of refrigeration cycle D Side, the low-temperature side evaporator C2 shell side of the refrigeration cycle C, the refrigeration cycle B low-temperature evaporator B2 shell side, and the refrigeration cycle A low-temperature evaporator A2 shell side. It is pressurized and flows out of the outlet pipe 4.

This embodiment is configured as described above.
Now, assuming that the flow rate of the fluid to be cooled is constant at Q (m ³ / min),
It is assumed that each evaporator of each refrigeration cycle has a capability of cooling the fluid to be cooled of Q (m ³ / min) by 1 ° C., and the case where the refrigeration cycle cools the outlet temperature of the fluid to be cooled to 24 ° C. .

First, when the temperature of the fluid W to be cooled exiting the heat radiating pipe 51 is 32 ° C., the necessary cooling capacity can be obtained by operating all four refrigeration cycles as shown in FIG. The temperatures of the cooled fluid entering and leaving the evaporators in the cycle are as shown in FIG. 3, and the average temperatures are as shown in Table 1. Table 1 also shows average temperatures when the refrigeration cycles were simply arranged in parallel and when simply arranged in series.

[0017]

[Table 1]

Next, when the temperature of the fluid to be cooled W that has exited the heat radiating pipe 51 has dropped to 28 ° C., as shown in FIG.
The required cooling capacity can be obtained by operating the stage, for example, the refrigeration cycles C and D. At this time, the temperature of the fluid to be cooled and the temperature of the fluid to be cooled entering each evaporator of the refrigeration cycles C and D are as shown in FIG.
Therefore, the average temperature is as shown in Table 2.

[0019]

[Table 2]

As is clear from Tables 1 and 2, in this embodiment, the average temperature of the fluid to be cooled in the refrigeration cycle during operation is equal among the refrigeration cycles, that is, when the refrigeration cycle is simply arranged in series. At the same time, the load is made more uniform, and at the same time, when the individual refrigeration cycles are arranged in parallel because the average temperature at low load is higher than when each refrigeration cycle is arranged in parallel The deterioration of the cooling efficiency at a low load is minimized and the cooling efficiency is high.

Next, in this embodiment, the refrigerant is diverted between the capillary tube and the evaporator. At the branch point, that is, at the inlet of the high-temperature capillary tube and the inlet of the low-temperature capillary tube, the pressures of both are naturally equal. At the junction, that is, at the outlet of the high-temperature side evaporator and the outlet of the low-temperature side evaporator, it is necessary that the pressures of both are naturally equal. On the other hand, if the configuration of the capillary tube and the evaporator are the same on the high-temperature side and the low-temperature side, the refrigerant will evaporate more in the high-temperature side evaporator, so the flow path resistance will be larger, so the flow rate will be smaller and the cooling capacity will be lower. In the low-temperature side evaporator, the refrigerant evaporates less, so that the flow path resistance is smaller, so that the flow rate is larger and the cooling capacity is larger. Moreover, the difference between the flow path resistance on the high temperature side and the flow path resistance on the low temperature side is as large as in the refrigeration cycle A, and not so large in the refrigeration cycle D. As a result, the fluid to be cooled sequentially reaches the high-temperature side evaporator D1 of the refrigeration cycle D from the high-temperature side evaporator A1 of the refrigeration cycle A, and sequentially starts from the low-temperature side evaporator D2 of the refrigeration cycle D. In the process of returning to the above, the cooling is not so much at first, gradually cooled, and finally cooled greatly, that is, it is not completely linearly cooled as shown in Table 1. Therefore, the average temperature of the refrigeration cycle A is lower, the average temperature of the refrigeration cycle D is higher,
The equalization of the load for each refrigeration cycle is slightly degraded.

Therefore, in order to further equalize the load for each refrigeration cycle, the flow path resistance on the high temperature side is made smaller than the flow path resistance on the low temperature side, and the difference between the two is larger in the refrigeration cycle A. There is a need to. In this case, for example, all 8
It is difficult to make the stage evaporators differently, and it is easier to make all eight capillary tubes differently. That the number of number and the low temperature side capillary tube of the X (X = A~D) high temperature side capillary tube of the refrigeration cycle, when the I _X1 and I _{X2 respectively, I A1> I B1> I} C1> I D1> It can be formed so that I _D2 > I _C2 > I _B2 > I _A2 or at least I _A1 ≧ I _B1 ≧ I _C1 ≧ I _D1 ≧ I _D2 ≧ I _C2 ≧ I _B2 ≧ I _A2. preferable. Therefore, in this embodiment, the number of the capillary tubes is configured as shown in Table 3.

[0023]

[Table 3]

As shown in Table 3, in the refrigerating cycle D, the number of the high-temperature side capillary tubes is equal to the number of the low-temperature side capillary tubes, because the number of the capillary tubes can be changed only to discrete. In order to make the flow path resistance on the high-temperature side smaller than the flow path resistance on the low-temperature side, and to increase the difference between the two in the refrigeration cycle A, the length of the capillary tube may be changed. That is, assuming that the length of the high-temperature side capillary tube and the length of the low-temperature side capillary tube of the Xth (X = A to D) refrigeration cycle are L _X1 and L _X2 respectively, L _A1 > L _B1 > L _C1 > L _D1 > L _D2 > L _C2 > L _B2 > L _A2 , or at least, L _A1 ≧ L _B1 ≧ L _C1 ≧ L _D1 ≧ L _D2 ≧ L _C2 ≧ L _B2 ≧ L _A2 Is preferred. At this time, there is an advantage that the flow path resistance can be continuously changed.

[0025]

Second Embodiment In the first embodiment, the number M of expansion valves and evaporators in each refrigeration cycle is M = 2.
A case where M = 4 will be described as an embodiment. However, the number of refrigeration cycles is four as in the above embodiment. At this time, as shown in FIG. 5, the fluid to be cooled W that has exited the heat radiating pipe of the cooling tower is passed through the first evaporator of each refrigeration cycle, and the order of the refrigeration cycle passed through the first evaporator is as follows. Pass through the second evaporator of each refrigeration cycle in reverse order, pass through the third evaporator of each refrigeration cycle,
Pass through the fourth evaporator of each refrigeration cycle in the reverse order of the refrigeration cycle passed through the evaporator. That is, the fluid to be cooled passes through the evaporator according to the numerical order in Table 4. Note that the order of passing through the third evaporator can be newly set completely independently of the order of passing through the first evaporator. Therefore, as shown in Table 5, it is not possible to pass the fluid to be cooled. Absent.

[0026]

[Table 4]

[0027]

[Table 5]

Thus, of the 16 evaporators, the inlet temperature of the fluid to be cooled in the first evaporator is 32 ° C. as in the previous embodiment, and the outlet temperature of the 16th evaporator is 24 ° C. Therefore, since each evaporator is cooled by (32−24) /16=0.5 (° C.), the inlet temperature of the m-th evaporator is 32−0.5 × (m−1) (° C.) and the outlet temperature is 32-0.5 × m (° C.). Therefore, the average temperature of the m-th evaporator is 32-0.5 x (m-1 / 2) = 32.25-0.5 x m (° C). Therefore, the average temperature T of the fluid to be cooled in each refrigeration cycle is expressed as follows: T = [Σ (32.25−0.5 × m)] / 4 = 32 where と し て is the sum of the four evaporators of the refrigeration cycle. .25−0.5 × (Δm) / 4 (° C.), where Δm is Δm for any refrigeration cycle.
= 34, the average temperature T of any of the refrigeration cycles is T = 28 ° C., which is the same as in the first embodiment.

Next, when the inlet temperature of the fluid to be cooled in the first evaporator drops to 28 ° C., the two refrigerating cycles are stopped, and only the eight evaporators of the two refrigerating cycles in operation are operated. Table 6 shows the order in which the fluid to be cooled passes, that is, the cooling order m.

[0030]

[Table 6]

The average temperature of the m-th evaporator is 28-0.5.times. (M-1 / 2) = 28.25-0.5.times.m (.degree. C.) in the same manner as described above. The average temperature T of the fluid to be cooled in the refrigeration cycle is as follows: T = [Σ (28.25−0.5 × m)] / 4 = 28.25−0.5 × (Σm) / 4 (° C.) , Δm is Δm for any refrigeration cycle
= 18, the average temperature T of any of the refrigeration cycles is T = 26 ° C., which is the same as in the first embodiment. That is, even when M = 2, 4, 8,..., The results are all the same as in the first embodiment, that is, when M = 2.

[0032]

Third Embodiment Next, as a third embodiment, when the number M of expansion valves and evaporators in each refrigeration cycle is M = 3,
The fluid to be cooled, which has passed through the cooling pipe of the cooling tower, is passed through the first evaporator of each refrigeration cycle as shown in Table 7, and the order of the refrigeration cycle passed through the first evaporator is reverse to the order of the refrigeration cycle. Pass through the second evaporator of each refrigeration cycle and pass through the third evaporator of each refrigeration cycle. The order of passing through the third evaporator of each refrigeration cycle may be independent of the order of passing through the first evaporator.

[0033]

[Table 7]

Thus, in each of the twelve evaporators, the fluid to be cooled is cooled by (32-24) / 12 = 2/3 (° C.), and the inlet temperature of the m-th evaporator becomes 32- 2/3 × (m−1) (° C.), and the outlet temperature is 32−2 / 3 × m (° C.). Therefore, the average temperature of the m-th evaporator is 32−2 / 3 × (m−1 / 2) = 32 +／− 2/3 × m (° C.). Therefore, the average temperature T of the fluid to be cooled in each refrigeration cycle is represented by the following equation: Σ is the sum of the three evaporators of the refrigeration cycle, and T = [Σ (32 + 1 / 3-2 / 3 × m)] / 3 = 32 + 1 / 3-2 / 3 × (Σm) (℃) and becomes, .SIGMA.m is different for each refrigeration cycle, the average temperature T _X of the refrigeration cycle X (X = A~D) is, T _a = 28.3 _{℃, T B = 28.1 ℃ T} C = 27.9 ℃, becomes T _D = 27.7 ℃, load between the refrigeration cycle cross is not a uniform. The same applies when the inlet temperature of the fluid to be cooled in the first evaporator is reduced to 28 ° C.

That is, when M is an odd number, the sum of the order of the evaporators through which the fluid to be cooled passes in each refrigerating cycle, Δm
Are not equal to each other, the load between the refrigeration cycles is not equal, but the degree of the unevenness is reduced as compared with when the refrigeration cycles are simply arranged in series. The reason is that when M = 3, the first and second evaporators are equal, and only the third evaporator causes unevenness. Therefore, the degree of imbalance decreases as M is increased as M = 3, 5, 7,..., Oddly, and finally becomes the same as when M is even, that is, when M = 2.

As described above, when M = 1, that is, when the refrigeration cycles are simply arranged in series, the loads between the refrigeration cycles are unbalanced. When M = 2, the loads are equal. Is reduced only to the third evaporator, and M = 4
In the case of M = 2, it is the same as M = 2. When M = 5, the unequal portion is reduced to only the fifth evaporator, and when M = 6, it becomes the same as M = 2.

[0037]

Fourth Embodiment Next, in each of the above embodiments, the entire flow rate Q of the fluid to be cooled sequentially passed through all the evaporators. FIG. 6 shows a fourth embodiment of the second embodiment shown in Table 4 and FIG. 5 in which the fluid to be cooled is divided in half and sequentially passed through all 16 evaporators. Such a configuration is preferable because the flow path resistance of the fluid to be cooled is reduced.

[0038]

Fifth Embodiment In the first to fourth embodiments, the passage for passing the fluid to be cooled in each evaporator is one chamber.
Instead of providing a plurality of or even number of evaporators, the passage through which the fluid to be cooled of each evaporator passes may be divided into a plurality of or even number of rooms to obtain the same effects as those of the above embodiments. it can. First, in the fifth embodiment shown in FIG. 7, each of the four refrigeration cycles A, B, C and D has one evaporator A1, B1, C1 and D1, but the fluid to be cooled in each evaporator is The shell side that passes is divided into two rooms, and the fluid W to be cooled is first supplied to the evaporator A1 of the refrigeration cycle A.
After passing through one room A1a on the shell side, the refrigeration cycle B
Pass through one room B1a on the evaporator B1 shell side, and finally pass through one room D1a on the evaporator D1 shell side of the refrigeration cycle D. It passes through the other room D1b, and finally passes through the other room A1b on the evaporator A1 shell side of the refrigeration cycle A in the same manner. Even when formed in this way, the same effects as in the above embodiments can be obtained.

[0039]

Sixth Embodiment Next, FIG. 8 shows a sixth embodiment, which has three refrigeration cycles A, B and C, each refrigeration cycle having two evaporators A1, A2; B1, B
2; C1, C2, and four shells (the evaporator A1 has A
1a, A1b, A1c and A1d),
Each room is selected as two rooms (a, b) on the high temperature side and two rooms (c, d) on the low temperature side. The fluid to be cooled W is divided into two and the two high-temperature rooms (a,
b) in parallel, then merged once at the header, then split again into two, and in the reverse order of the refrigeration cycle that passed through the two high-temperature rooms (a, b), the two on the low-temperature side Pass through the rooms (c, d) in parallel. In the present embodiment, the number of evaporators in each refrigeration cycle is two, but may be one or three. Also, the passage through which the fluid to be cooled of each evaporator passed was divided into four rooms,
The refrigeration cycle may be divided into two, or the degree of achievement of equalizing the load of each refrigeration cycle may be slightly lower, but may be divided into three rooms.

[0040]

Seventh Embodiment Finally, FIG. 9 shows a seventh embodiment. In the third embodiment, when the number of evaporators for each refrigeration cycle was odd, the load for each refrigeration cycle could not be completely uniform. However, even when the number of evaporators was odd, each refrigeration cycle If the passage through which the fluid to be cooled passes is divided into an even number of rooms for each one evaporator, the load for each refrigeration cycle can be made uniform. That is, in FIG. 9, each refrigeration cycle A, B, C and D has five evaporators (A1, A2, A3, A4 and A5 for the refrigeration cycle A), of which the third evaporators A3, B3 and C3 are provided.
The passage through which the fluid to be cooled passes is divided into two rooms (A3a and A3b for the evaporator A3). However, in FIG. 9, the passage through which the fluid to be cooled passes is divided into two rooms so that all the evaporators other than the third evaporator have the same configuration. The fluid to be cooled W is first divided into five, and passes in parallel through two rooms (a, b) of the first and second evaporators and one room (a) of the third evaporator of each refrigeration cycle. Then, they are merged once at the header and then divided again into five, and in the reverse order to the order of passing through each refrigeration cycle, the remaining one room (b) of the third evaporator of each refrigeration cycle and the fourth and fourth chambers It passes through two rooms (a, b) of the fifth evaporator in parallel. Even when formed in this way, the same effects as in the above embodiments can be obtained.

[0041]

As described above, according to the present invention, an even number of evaporators are provided in each refrigeration cycle, or the passage through which the fluid to be cooled of each evaporator passes is divided into an even number of chambers, and the fluid to be cooled is provided. Through each half of each evaporator of each refrigeration cycle, or through half of the even number of rooms of each evaporator, and reverse each refrigeration cycle in the reverse order of the refrigeration cycle. Equalize the load of each refrigeration cycle because it is characterized by passing the other half of the even number of each evaporator in the cycle or the other half of the even number of rooms of each evaporator. Can be. Further, even when the number of evaporators in each refrigeration cycle and the number of passages through which the fluid to be cooled in each evaporator is an odd number, the load of each refrigeration cycle can be made uniform to a certain extent.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a first embodiment of the present invention.

FIG. 2 is a front view showing the expansion valve of the embodiment.

FIG. 3 is a temperature distribution diagram of main parts during full load operation of the embodiment.

FIG. 4 is a temperature distribution diagram of main parts during half-load operation of the embodiment.

FIG. 5 is a main part system diagram showing a second embodiment.

FIG. 6 is a main part system diagram showing a fourth embodiment.

FIG. 7 is a main part system diagram showing a fifth embodiment.

FIG. 8 is a main part system diagram showing a sixth embodiment.

FIG. 9 is a main part system diagram showing a seventh embodiment.

FIG. 10 is a temperature distribution diagram of a main part during full load operation of the cooling device which can be considered more easily than the conventional example.

FIG. 11 is a temperature distribution diagram of a main part of the cooling device during a half-load operation.

FIG. 12 is a temperature distribution diagram of a main part of another cooling device during full load operation, which can be considered more easily than the conventional example.

FIG. 13 is a temperature distribution diagram of a main part of the cooling device during a half-load operation.

[Explanation of symbols]

A, B, C, D: refrigeration cycle A1, A2, ...,
D1, D2, ...: Evaporators A1a, A1b, ...: Room W: Cooled fluid 1: Inlet piping 2: Booster pump 3: Circulation pump 4: Outlet piping 11, 21, 31, 41: Compressors 12, 22 ,
32, 42: condensers 13, 14, 15, 16, ..., 43, 44, ...: expansion valves 50: cooling towers 51: radiating pipes 55: fans
56: motor 60: water sprinkling part 61: water reservoir 62: water receiving tank 6
3: Pump 64: Piping

Claims (9)

(57) [Claims] 1. A compressor, a condenser, 2N (N is a natural number) expansion valves, and 2N evaporators, respectively. After passing the refrigerant in the order of the compressor and the condenser, the refrigerant is cooled. Dividing into the 2N flows, passing each refrigerant in the order of each expansion valve and the evaporator, and thereafter providing a plurality of refrigeration cycles for returning each refrigerant to the compressor by merging each refrigerant, A cooling tower having a water spray device for spraying water to the heat radiating pipe and each condenser, and a fan for blowing air to the heat radiating pipe and each condenser is provided, and a fluid to be cooled passes through the heat radiating pipe of the cooling tower. After that, the ith evaporator (i = 1 to 1)
2N), the refrigeration cycle is passed through the evaporator of each refrigeration cycle and passed through the 2n-1 evaporator (n = 1 to N) of each refrigeration cycle in the reverse order of the refrigeration cycle. Cooling device passed through the second n evaporator of the cycle. 2. The cooling fluid is passed through a radiating pipe of the cooling tower, and then passed through the first to N evaporators of each refrigeration cycle, and the order of the refrigeration cycle is reversed. 2. The cooling device according to claim 1, wherein the cooling device is passed through N + 1 to 2N evaporators of each refrigeration cycle. 3. A compressor, a condenser, 2N + 1 (N is a natural number) expansion valves, and 2N + 1 evaporators, respectively.
After passing the refrigerant in the order of the compressor and the condenser, the refrigerant is divided into the 2N + 1 streams, each refrigerant is passed in the order of each expansion valve and the evaporator, and then the respective refrigerants are merged. A cooling system including a plurality of refrigeration cycles returned to the compressor, a radiating pipe, a water spray device for spraying water to the radiating pipe and the condensers, and a fan for blowing air to the radiating pipes and the condensers. A tower is provided, and after the fluid to be cooled passes through the radiating pipe of the cooling tower, the cooling fluid is passed through the evaporator of each refrigeration cycle for each i-th evaporator (i = 1 to 2N + 1). A cooling device that has passed through the 2n-th evaporator of each refrigeration cycle in a reverse order to the order of the refrigeration cycles that have passed through the 2n-1 evaporators (n = 1 to N). 4. A passage through which at least the fluid to be cooled of the (N + 1) th evaporator among the evaporators of each of the refrigeration cycles is divided into an even number of chambers, and the fluid to be cooled is dissipated to a radiating pipe of the cooling tower. After passing through the first cycle of each refrigeration cycle.
ＮN and half of said even number of chambers of the (N + 1) th evaporator are passed through, and the even numbered chambers of the (N + 1) th evaporator of each refrigeration cycle are reversed in the reverse order of the refrigeration cycle passed through. 4. The cooling device according to claim 3, wherein the remaining half of the cooling water passes through the (N + 2) to (2N + 1) th evaporators. 5. A plurality of refrigeration cycles each comprising a compressor, a condenser, and one or more expansion valves and an evaporator, the refrigerant being passed in that order and returning to the compressor. The passage through which the fluid to be cooled of each evaporator passes is divided into a plurality of rooms, and a heat radiating pipe, a water spray device for watering the heat radiating pipe and each of the condensers, the heat radiating pipe and each of the condensers A cooling tower having a fan for blowing air is provided, and after the fluid to be cooled is passed through the heat radiation pipe of the cooling tower, the cooling fluid is passed through a part of the plurality of rooms of each evaporator of each refrigeration cycle, and passed therethrough. A cooling device that passes the remainder of the plurality of rooms of each evaporator in each refrigeration cycle in the reverse order of the refrigeration cycle. 6. The cooling device according to claim 1, wherein the expansion valve has a refrigerant pressure substantially equal at an outlet of each evaporator of each of the refrigeration cycles. 7. The cooling device according to claim 1, wherein each expansion valve of each refrigeration cycle is constituted by a capillary tube. 8. The capillary tube according to claim 7, wherein the length of the upper-order capillary tube in the order in which the fluid to be cooled passes through each capillary tube is shorter than or equal to the length of the lower-order capillary tube. Cooling system. 9. The cooling system according to claim 7, wherein the number of capillary tubes in the upper order in the order in which the fluid to be cooled passes through each capillary tube is larger than or equal to the number of capillary tubes in the lower order. apparatus.