JP4017100B2 - Regenerative heat refrigeration system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cold storage heat refrigerating apparatus including a heat storage unit that includes a cold storage heat medium and includes a heat exchanger for cold storage heat.
[0002]
[Prior art]
A conventional regenerative heat refrigerating apparatus incorporates a regenerator / refrigerant heat exchanger and a regenerator heat exchanger in the same regenerator as described in, for example, Japanese Patent Application Laid-Open No. 64-10062. The arrangement method of the heat transfer tubes of the respective heat exchangers is not particularly described.
[0003]
[Problems to be solved by the invention]
In the case of a heat storage unit that does not have an agitation function in the heat storage tank, the temperature distribution of the cold storage heat medium in the heat storage tank is high on the upper side and low on the lower side due to natural convection during cold storage use. In addition, since the cool storage heat medium is cooled only on the cool storage / cold storage heat exchanger side during cold storage, the cool storage heat medium around the cool storage / cold storage heat exchanger and cool storage heat exchanger is also used during cold storage. Therefore, the temperature of the cold storage heat medium around the heat exchanger for cold storage is high.
[0004]
As described above, since the arrangement of the heat transfer tubes of the respective heat exchangers is not particularly defined as described above, when the heat exchanger for cold storage is arranged on the upper side, the surroundings of the heat exchanger are caused by the temperature distribution. The temperature of the regenerator heat storage medium becomes so high that heat exchange is not sufficiently performed and the required refrigeration capacity may not be obtained.
[0005]
An object of the present invention, during cold storage use by cold storage use only heat exchangers, so as to cold storage heat medium low have temperature heat exchanger, the cold storage heat type capable of securing a refrigerating capacity that is required It is to provide a refrigeration apparatus.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the present invention, a compressor and a refrigerator having a condenser, cold storage and cold storage use the same heat storage and cold storage, cold storage utilization heat exchangers capable of the cold storage use only heat exchangers of A heat storage unit for storing water, which is a cold storage heat medium in the heat storage tank, by natural convection by cooling of the cold storage / cold storage heat exchanger without having a stirring function built in the tank, and the refrigerator includes A first refrigeration apparatus including a low-pressure load cooler and the cold storage / cold storage heat exchanger and capable of cooling, cold storage and cold storage operation, and a low-pressure load cooler and heat exchange dedicated to the cold storage use in Ru cold storage heat refrigeration device name from the cooling and cold storage utilization operation possible second refrigeration system comprises a vessel, a cold storage use only heat exchangers of the second refrigeration system, wherein the first refrigeration system is cooled by the cold storage, cold storage available heat exchange own Convection by to move water heat exchanger downwardly, in which is arranged below the heat exchanger for the cold storage-cold accumulating interest.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the regenerative heat type refrigeration apparatus of the present invention will be described with reference to the drawings.
First, a heat storage unit incorporated in the cold storage heat type refrigeration apparatus of the present invention will be described.
FIG. 1 is a schematic cross-sectional view of a first embodiment of a heat storage unit. In the heat storage tank 33 having the lid 33a, a cold storage heat medium 34 (for example, water) is stored, and a heat exchanger 35 (thick solid line) for cold storage and cold storage and a heat exchanger 36 dedicated for cold storage use are the same heat storage tank. 33 is built in. As will be described later, the heat exchanger 35 for cold storage and cold storage has a refrigerant pipe 61a connected at one end to a condenser and a compressor, and a refrigerant pipe 61b connected at the other end to a load cooler. Then, it is used for cold storage and cold storage use of the first refrigeration apparatus. Similarly, the heat exchanger 36 dedicated to cold storage is connected to the second refrigeration apparatus and dedicated to cold storage. Further, the heat exchanger 36 dedicated to cold storage use is disposed below the heat exchanger 35 for cold storage and cold storage use.
[0012]
The reason is that the temperature distribution of the cold storage heat medium 34 in the heat storage tank 33 during cold storage use is such that the upper temperature is high and the lower temperature is low. That is, during the cold storage use, the cold storage / cold storage heat exchanger 35 exchanges heat with the ice produced by itself. On the other hand, the heat exchanger 36 dedicated for cold storage use exchanges heat with water cooled by the ice produced by the heat exchanger 35 for cold storage / storage use. When water is used as the cold storage heat medium 34, the density of the water increases as the temperature decreases, and the water moves downward by convection. For this reason, the lower side becomes a low temperature (4 ° C. to 0 ° C.), and the lower heat exchanger 36 dedicated to cold storage always exchanges heat with the cold storage heat medium 34 at a low temperature, so that stable heat exchange is achieved. It becomes possible. In order to enable stable heat exchange in this way, the heat exchanger 36 dedicated to cold storage use is disposed below the heat exchanger 35 for cold storage and cold storage use.
According to the present embodiment, the heat exchanger 36 dedicated to cold storage use on the lower side always exchanges heat with the cold storage heat medium 34 having a low temperature, and stable heat exchange becomes possible.
[0013]
FIG. 2 is a schematic cross-sectional view of Reference Example 1 of the heat storage unit. The present reference example 1 includes a heat transfer tube of a heat storage / cooling heat exchanger 35 connected to the first refrigeration device, and a heat transfer tube of a heat exchanger 36 dedicated to cold storage connected to the second refrigeration device; Are arranged alternately. The reason for the alternate arrangement is that although the temperature distribution is slightly inferior to that of the embodiment of FIG. 1, it is not affected by the water temperature around the heat transfer tube of the heat exchanger 36 dedicated to cold storage use, so it is good even in the latter half of use. Heat exchange is possible. According to this reference example 1 , good heat exchange is possible even in the latter half of use.
[0014]
FIG. 3 is a schematic cross-sectional view of Reference Example 2 of the heat storage unit. In this reference example 2 , the heat transfer tube of the heat exchanger 36 exclusively used for cold storage connected to the second refrigeration apparatus is used as the heat transfer pipe of the heat exchanger 35 used for cold storage and cold storage connected to the first refrigeration apparatus. It arrange | positions between pitches (it arrange | positions the heat exchanger tube of the heat exchanger 36 between the heat exchanger tubes of the heat exchanger 35 of cold storage / cold storage utilization). The reason is that the temperature distribution is improved compared to Reference Example 2 in FIG. 2 and there is no unevenness of melting, and good heat exchange is possible even in the latter half of use. According to this reference example 2 , the temperature distribution is further improved, and good heat exchange is possible even in the latter half of use.
[0015]
FIG. 4 is a schematic cross-sectional view of Reference Example 3 of the heat storage unit. In this third reference example , the heat exchanger 36 dedicated for cold storage use of the second refrigeration apparatus is disposed in a part of the lower side of the heat exchanger 35 for cold storage / cold storage use of the first refrigeration apparatus, and the upper part thereof is heated. By arranging the exchanger 36 and the heat exchanger 35 alternately, the temperature distribution can be improved and good heat exchange can be achieved even in the latter half of use.
[0016]
FIG. 5 is a schematic cross-sectional view of Reference Example 4 of the heat storage unit. In this reference example 4 , the heat exchanger 36 dedicated to the cold storage use of the second refrigeration apparatus is arranged in a part of the lower side of the heat exchanger 35 for the cold storage and cold storage use of the first refrigeration apparatus, and the upper part is heated. By disposing the exchanger 36 between the pitches of the heat exchanger 35, the temperature distribution can be further improved, and good heat exchange can be achieved even in the latter half of use.
[0017]
Next, a cold storage type refrigerating apparatus incorporating the heat storage unit shown in FIG. 1 will be described.
FIG. 6 is a cycle system diagram of an embodiment of a regenerative heat refrigerating apparatus.
The regenerative heat storage type refrigeration apparatus can be broadly divided into a first refrigeration apparatus A capable of cooling, storing and using a low-pressure load, and a second refrigeration apparatus B capable of cooling and storing a low-pressure load. It is composed of Details are as follows.
[0018]
The first refrigeration apparatus A capable of cooling, storing and using a low-pressure load is composed of a refrigerator 1, load coolers 2a and 2b, and a heat storage unit 3. In detail, the refrigerator 1 is A compressor 11 that compresses the refrigerant gas, and a condenser 12 that dissipates heat held in the high-temperature and high-pressure refrigerant gas to the atmosphere to form a liquefied refrigerant, and the load coolers 2a and 2b include the liquefied refrigerant The two expansion valves 21a and 21b connected in parallel for adiabatic expansion of the refrigerant, the evaporators 22a and 22b that absorb heat from the load side and evaporate the liquefied refrigerant to become gas refrigerant, and the flow rate of the refrigerant gas The heat storage unit 3 is composed of cooler solenoid valves 23a and 23b for controlling, and is used for cold storage heat for adiabatically expanding into a refrigerant pipe 61a branched from the refrigerant pipe 61 on the front side of the electromagnetic valve 32a for opening and closing the flow path. Open expansion valve 31 and flow path And an electromagnetic valve 32b for opening and closing the flow path in the refrigerant pipe 61b branched from the front and rear sides of the load coolers 2a and 2b. 32d is connected, and these pipes 61a and 61b are connected to the cold storage / cold storage heat exchanger 35 in the heat storage tank 33.
[0019]
Next, the second refrigeration apparatus B dedicated to cooling of the low-pressure side load and cold storage use will be described.
The second refrigeration apparatus B has basically the same configuration as that of the first refrigeration apparatus A except that the heat exchanger is dedicated to cold storage use. That is, the refrigerator 4 composed of the compressor 41 and the condenser 42 in the refrigerant pipe 62, the two expansion valves 51a and 51b for the cooler arranged in parallel, the evaporators 52a and 52b, the solenoid valve 53a for the cooler, The low-pressure side load coolers 5a and 5b configured by 53b are connected, and the second refrigerating apparatus B is configured by the electromagnetic valve 32f for opening and closing the flow path.
[0020]
A configuration in which the second refrigeration apparatus B shares the heat storage tank 33 with the first refrigeration apparatus A is as follows.
In other words, a cold storage dedicated heat exchanger 36 built in the heat storage tank 33 is connected to a refrigerant pipe 62a that is branched from before and after the electromagnetic valve 32f. Further, an electromagnetic valve 32e for opening and closing the flow path is connected to the front side of the flow path flowing into the heat storage tank 33, and a check valve 37 is connected to the rear side of the flow path flowing out of the heat storage tank 33. For example, an on-off valve can be used as long as it can prevent or block backflow instead of the check valve 37. However, if the check valve is used, control of opening and closing is unnecessary, and management becomes easy. .
[0021]
In the above configuration, a case where the cooling operation and the cold storage operation of the low-pressure side load by the first refrigeration apparatus A and the cooling operation of the low-pressure side load by the second refrigeration apparatus B are simultaneously performed will be described with reference to FIG.
When the cold storage operation and the low-pressure load cooling operation are performed simultaneously, the solenoid valves 32a and 32c and the cooler solenoid valves 23a and 23b are opened, and the solenoid valves 32b and 32d are closed. In this state, as shown by the thick solid line (however, only the refrigerant pipe is shown by the thick solid line, and the heat exchanger is shown by the thin line), the first refrigeration apparatus A uses the low-pressure load coolers 2a and 2b. The returned refrigerant gas is compressed by the compressor 11 and becomes a high-temperature / high-pressure refrigerant gas. The high-temperature and high-pressure refrigerant gas is radiated to the atmosphere side by the condenser 11 to become a high-pressure liquid refrigerant. The high-pressure liquid refrigerant is adiabatically expanded by the cold-storage heat expansion valve 31 and the cooler expansion valves 21a and 21b to become a low-temperature saturated liquid refrigerant and flows to the low-pressure load coolers 2a and 2b and the heat storage unit 33, respectively.
[0022]
In the heat storage tank 33, the low-temperature saturated liquid refrigerant absorbs heat from the cold storage heat medium 34 by the cold storage / cold storage heat exchanger 35 to become a gas refrigerant, and the cold storage heat medium 34 is cooled and stored cold. In the low-pressure side load coolers 2a and 2b, the saturated liquid refrigerant absorbs heat from the cooling load side to become gas refrigerant, and cools the load.
[0023]
In the second refrigeration apparatus B, the solenoid valve 32e is closed and the solenoid valve 32f is opened, and the cooling operation of the load is performed independently without going through the heat storage unit 3.
When the low-pressure side load coolers 2a and 2b are generally showcases or unit coolers, the cooling load is reduced at night, and therefore, cold storage is performed with the surplus refrigeration capacity of the refrigerator. If the cooling load is very small or no cooling load is required, it is not necessary to flow the refrigerant to the low-pressure load coolers 2a and 2b. In this case, only the cold storage operation is performed. On the contrary, if the cold storage to the cold storage heat medium 34 is completed, the cold storage operation is stopped, and only the low-pressure load coolers 2a and 2b are operated.
[0024]
Next, the case where load cooling, cold storage, and cold storage use operation are simultaneously performed by the first and second refrigeration apparatuses A and B will be described with reference to FIG.
In the case of the cold storage use operation, in the first refrigeration apparatus A, the electromagnetic valves 32a and 32c are closed and the electromagnetic valves 32b and 32d are opened. Further, in the second refrigeration apparatus, the electromagnetic valve 32f is closed and the electromagnetic valve 32e is opened.
[0025]
In the above state, in the first refrigeration apparatus A, heat is exchanged in the condenser 12 and the refrigerant is liquefied. As shown by a thick solid line, the liquefied refrigerant passes through the electromagnetic valve 32b and is used for heat storage / cold storage utilization heat exchange. After entering into the vessel 35 and exchanging heat with the cold storage heat medium 34 in the heat storage tank 33 to be in a supercooled state, it is supplied to the low-pressure load coolers 2a and 2b through the electromagnetic valve 32d.
[0026]
Since the capacity of the refrigerator is generally selected based on the maximum load during the daytime in the summer, there is a margin in the freezing capacity of the refrigerator at night, which can be used for cold storage. Here, in the case where cold storage is performed in excess of the amount of cold storage heat used in the first refrigeration apparatus A, for example, cold storage is performed in the cold storage heat medium 34 on the assumption that the first refrigeration apparatus A and the second refrigeration apparatus B are used. In this case, or when the load is reduced and the amount of cold storage heat to be used is also reduced, the excess cold heat stored in the second refrigeration apparatus B is used. Therefore, the solenoid valve 32e is opened and the solenoid valve 32f is closed, and the refrigerant flows through the cold storage use heat exchanger 36. Thereby, the surplus stored in the cold storage heat medium 34 can be used effectively. That is, the freezing capacity margin of the first refrigeration apparatus A can be used effectively.
[0027]
By interposing the electromagnetic valve 32e and the check valve 37 before and after the heat storage tank 33 as in the above embodiment, the following different actions are performed compared to the case of the electromagnetic valve 32f alone.
That is, in the case of only the solenoid valve 32f, when the first refrigeration device performs a cold storage operation and the second refrigeration device performs a cooling operation in which neither cold storage nor cold storage is used, a part of the high-temperature liquid refrigerant passes through 62a. However, a phenomenon may occur in which heat is exchanged with the cold storage heat medium 34 and the cold storage heat medium 34 is warmed. However, if the solenoid valve 32e is closed, liquid from the upstream side may flow. Inflow of the refrigerant is eliminated, and the reverse flow of the liquid refrigerant is also eliminated by the check valve 37 from the downstream side, and as a result, the phenomenon that the liquefied refrigerant is accumulated in the cold-storage-use heat exchanger 36 does not occur. For this reason, the cold storage heat medium 34 is not warmed during the cold storage operation, and the cold storage operation can be performed smoothly.
[0028]
In addition, the said Example has the 1st freezing apparatus A which has the cooler for low voltage | pressure side loads, and the heat exchanger which can perform cold storage and cold storage utilization, and the low pressure side load cooler and the heat exchanger only for cold storage utilization. Although the regenerative heat type refrigeration apparatus configured by one set with each of the second refrigeration apparatuses B has been described, when a plurality of first refrigeration apparatuses A and second refrigeration apparatuses B are appropriately combined, Even when one set of one refrigeration apparatus A and a plurality of second refrigeration apparatuses B are combined, or vice versa, the cold storage operation can be performed smoothly.
[0029]
【The invention's effect】
As described above, according to the present invention, by arranging the heat exchanger for cold storage / cold storage and the heat exchanger dedicated for cold storage in consideration of the temperature distribution of the cold storage heat medium, the heat dedicated for cold storage is used. during cold storage utilization by exchangers, Ki de be cold storage heat medium exchanges heat low had a temperature, it is possible to ensure cooling capacity required.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of a first embodiment according to a heat storage unit of a cold storage type refrigeration apparatus of the present invention.
2 is a schematic cross-sectional view of the heat storage unit of the cold storage heat refrigeration apparatus of Reference Example 1.
3 is a schematic cross-sectional view of the heat storage unit of the cold storage heat refrigeration apparatus of Reference Example 2.
4 is a schematic cross-sectional view of the heat storage unit of the cold storage heat refrigeration apparatus of Reference Example 3.
5 is a schematic cross-sectional view of the heat storage unit of the cold storage heat refrigeration apparatus of Reference Example 4.
FIG. 6 is a system diagram of a cycle of the embodiment according to the regenerative heat type refrigeration apparatus of the present invention.
7 is an explanatory diagram of a cycle during simultaneous operation of cooling and cold storage in the embodiment of FIG.
FIG. 8 is an explanatory diagram of a cycle at the time of simultaneous operation of cooling, cold storage and cold storage use in the embodiment of FIG. 6;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1,4 ... Refrigerator, 2a, 2b, 5a, 5b ... Low pressure side cooler, 3 ... Heat storage unit, 11, 41 ... Compressor, 12, 42 ... Condenser, 21a, 21b, 51a, 51b ... Cooling Expansion valve for vessel, 22a, 22b, 52a, 52b ... Evaporator, 23a, 23b, 53a, 53b ... Solenoid valve for cooler, 31 ... Expansion valve for cold storage heat, 32a, 32b, 32c, 32d, 32e, 32f ... Solenoid valve , 33 ... heat storage tank, 34 ... cold storage heat medium, 35 ... cold storage / heat utilization heat exchanger, 36 ... dedicated heat storage utilization heat exchanger, 37 ... check valve, 61, 61a, 61b, 62, 62a ... refrigerant piping.

Claims (1)

The heat storage without providing a refrigerator having a compressor and a condenser, the built-in stirring function cold storage and the cold storage, cold storage utilization heat exchanger that can cool storage utilizing the cold storage use dedicated heat exchanger on the same storage tank It includes a heat storage unit for cold storage of water is cold storage heat medium in the tank by natural convection by the cold storage, cold storage utilization heat exchangers cooling, and
The refrigerator is provided with a low-pressure side load cooler and the cold storage / cold storage heat exchanger and is capable of cooling, cold storage and cold storage operation , a low-pressure load cooler, and the cold storage use. in Ru cold storage heat refrigeration device name from the cooling and cold storage utilization operation possible second refrigeration system comprises a dedicated heat exchanger,
The heat exchanger dedicated to the cold storage use of the second refrigeration device is heat-exchanged with water cooled by the cold storage / cold storage use heat exchange of the first refrigeration device and moved downward by natural convection. cold storage heat refrigeration apparatus being characterized in that disposed below the heat exchanger for the cold storage-cold accumulating interest.

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