JPS6124636B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a heat storage device, and particularly to a heat storage device connected to a refrigeration cycle suitable for discharging and utilizing solidification heat of a coagulable heat storage material with a radiator. It is related to.

[Background of the invention]

In response to social demands for energy conservation, heat storage materials and heat storage devices are being developed, and in particular, development of latent heat type heat storage materials that utilize latent heat generated during solidification and melting of substances is progressing.

Further, development of a heat storage device in which a cooler is provided in a heat storage tank containing a coagulable heat storage material and the cooler is connected to refrigerant piping of a refrigeration cycle is also underway.

In this device, the refrigerant in the refrigeration cycle absorbs heat of solidification from the heat storage material through the cooler, and releases the heat in the radiator of the refrigeration cycle.

Heat is supplied to the heat storage material by using solar heat, residual heat from boilers, factory waste heat, etc. On the other hand, heat from the heat storage material can be used for various purposes such as heating, greenhouses, and drying. used for.

In such a heat storage device, solidification heat is released from the interface between the heat storage material that is crystallizing in the heat storage tank and the heat storage material that is in a liquid state and is transmitted to the cooler. There is a problem in that the heat transfer efficiency deteriorates due to being surrounded.

Therefore, it is an important issue to improve the heat transfer efficiency of the cooler, especially to maintain good heat transfer efficiency after the heat storage material starts crystallizing. Note that Japanese Patent Publication No. 53-9596 is related to the above.

[Object of the Invention] The present invention has been made in view of the above-mentioned problems or problems, and provides a main cooler in which the refrigerant of the refrigeration cycle absorbs the heat of solidification of the heat storage material in a heat storage device using a self-solidifying heat storage material. The purpose of the present invention is to provide a heat storage device in which the heat transfer efficiency of the heat storage material is maintained well even after the crystallization of the heat storage material has started, and which can be put to practical use and is highly profitable.

[Summary of the invention]

The configuration of the heat storage device according to the present invention is such that a coagulable heat storage material is housed in a heat storage tank, a main cooler is provided in the upper layer of the heat storage material, an auxiliary cooler is provided in the lower layer, and the auxiliary cooler or A nucleating agent is held in the vicinity thereof, and a heater for replenishing heat to the heat storage material is disposed within the heat storage material.

As an additional note, the heat storage device according to the present invention connects the main cooler and the supplementary cooler to refrigerant piping equipped with a compressor, a radiator, a radiator, and a pressure reducing means to form a closed circulation path. The structure is such that the heat of solidification of the material can be released through the heat radiator.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 1 to 11.
This will be explained with reference to the figures.

First, FIG. 1 is a schematic configuration diagram of a heat storage device according to an embodiment of the present invention, and FIG. 2 is a detailed diagram of the heat storage tank portion thereof.

In the figure, 1 is a heat storage tank, 2 is a coagulable heat storage material accommodated in the heat storage tank 1, and for example, 30
Calcium chloride hexahydrate coagulates and melts in C
It is CaCl.6H ₂ O (specific weight 1.5 g/cm ³ ).

3 is a main cooler disposed in the upper layer of the heat storage material 2; 4 is an auxiliary cooler disposed in the lower layer of the heat storage material 2; a nucleating agent 14 is located near the auxiliary cooler 4; installed.

5 is a radiator, 6 is a fan for the radiator 5, 7 is an expansion valve or capillary tube related to the pressure reducing means (the figure shows a capillary tube), 8 is a refrigerant pipe, 9 is a compressor, The main cooler 3 and the auxiliary cooler 4 are connected to a compressor 9 and a radiator 5 outside the heat storage tank 1.
and are connected by a refrigerant pipe 8 so as to constitute a refrigeration cycle having a closed circulation path.

The refrigerant (Tateeda Freon) in the refrigeration cycle is
The refrigerant is compressed by the compressor 9 and sent into the radiator 5, where it is cooled and releases the latent heat of condensation, thereby liquefying the refrigerant itself. The heat of condensation released by the radiator 5 is removed by air sent by a fan 6 outside the radiator 5. On the other hand, the condensate is
The refrigerant is fed through the refrigerant pipe 8 into the expansion valve or capillary tube 7, where it reaches the auxiliary cooler 4 while undergoing adiabatic expansion. The refrigerant in the auxiliary cooler 7 reaches the main cooler 3 while evaporating there. At this time, the refrigerant absorbs heat from the heat storage material 2 outside the auxiliary cooler 4 and the main cooler 3. The evaporated refrigerant is returned to the compressor 9 and repeats the same cycle again, but through the process described above, the heat in the heat storage material 2 is carried to the radiator 5, and if the radiator 5 is installed indoors, it can heat the room. The heat in the heat storage material 2 is utilized.

As described above, the heat storage device of this embodiment uses a material that can utilize solidification-temporal decomposition as the heat storage material 2. For example, when using hexahydrate calcium chloride CaCl ₂ 6H ₂ O as the heat storage material 2,
It solidifies while releasing 48 cal/g.

However, when this type of hydrated salt is generally used as the heat storage material 2, a significant supercooling phenomenon occurs, and the nucleating agent 14
Unless it is retained in the heat storage material 2, solidification will not start even if the heat storage material reaches the solidification temperature. .

Calcium chloride hexahydrate as heat storage material 2
When using CaCl ₂ .6H ₂ O, the nucleating agent 14 is strontium hydroxide Si (OE) _{2.8H 2} O.
etc. are good. stomach.

The temperature distribution of the heat storage material 2 in the heat storage tank 1 before solidification starts is lower in the lower layer due to convection.

If the auxiliary cooler 4 is provided in the lower layer inside the heat storage material 2,
Furthermore, the temperature of the lower layer becomes lower. Therefore, if a nucleating agent 14 is provided near the auxiliary cooler 4, crystal growth of the heat storage material 2 will start from the lower layer.

In FIG. 2, 2' indicates a crystallized heat storage material (hereinafter referred to as heat storage material crystal). Solidification heat is released from the interface between the heat storage material crystal 2' which continues to crystallize and the heat storage material 2 which is still in a liquid state. This solidification heat is transferred to the main cooler by convection of the heat storage material 2 which is in a liquid state. 3. Since the nucleating agent 14 is not provided near the main cooler 3, the heat storage material 2 is difficult to crystallize near the main cooler 3. As a result, the auxiliary cooler 4 is immediately surrounded by the heat storage material crystal 2'. Since the heat storage material crystal 2' has a low thermal conductivity, the heat transfer efficiency deteriorates, but since the main cooler 3 indirectly receives solidification heat from the heat storage material 2 in a liquid state, the heat transfer efficiency does not deteriorate immediately. . However, once the heat storage material 2 in the heat storage tank 1 has completely solidified, the main cooler 3 receives no solidification heat, so the heating capacity of the radiator 5 is almost completely lost. Therefore, it is necessary to supply heat into the heat storage material 2 by some means.

The embodiment shown in FIG. 1 uses the sun to replenish the heat storage material 2, and 13 is a heat collector as a heat collecting means, 10 is a pump, and 11 is a pipe for circulating hot water as a heat medium. be.

Hot water heated by a solar collector 13 that collects solar heat is pumped by a pump 10 to a heater 12 through a heat medium pipe 11, and is stored in heat while melting the heat storage material crystal 2 via the heater 12. It is something to do.

As a method of operating a heat storage device using solar heat, there are many methods in which solar heat is stored in the heat storage material 2 using a heat collector 13 and a pump 10 during the day, and heating is performed by operating the compressor 9 in the early morning or evening. .

In the detailed diagram of the heat storage tank in FIG. 2, the main cooler 3, the auxiliary cooler 4, and the heater 12 are equipped with heat transfer fins 3', 4', and 12', respectively.
This speeds up the solidification or melting rate and facilitates the transfer of heat.

FIG. 3 is a three-dimensional perspective view of the auxiliary exciter 4 and heater 12 shown in FIG. 2.

The auxiliary cooler 4 and the heater 12 are flexible pipes that are connected to the refrigerant tube 8 and the heat transfer pipe 11, respectively, and are bent several times into a U-shape. 4' and 12' to form a unit.

According to this embodiment, the following effects are achieved.

1 The nucleating agent 14 promotes crystal growth from the lower layer of the heat storage material 2.

2. Since the auxiliary cooler 4 and the heater 12 are provided as a unit in the lower layer of the heat storage material 2 housed in the heat storage tank 1, heat can be smoothly replenished when the heat storage material 2 finishes solidifying. .

3 The main cooler 3, auxiliary cooler 4, and heater 12 are provided with plate fins 3', 4', and 12', respectively.
, which speeds up the solidification or melting rate of the heat storage material 2 and facilitates the introduction and removal of heat.

4. Therefore, from these, the heat transfer efficiency of the hand cooler 3 is maintained at a good level even after the heat storage material starts to crystallize.

Next, another example of the auxiliary cooler and heater will be described in the fourth example.
This will be explained with reference to the figures and FIG.

FIG. 4 is a perspective view of an auxiliary cooler and heater section of a heat storage device according to another embodiment of the present invention, and FIG. 5 is a sectional view of FIG. 4.

In FIG. 4 and FIG. 5, 4A is a heat transfer pipe related to the auxiliary exciting cooler connected to the cooling pipe 8;
12A is a heat medium pipe related to the heater connected to the heat medium back pipe 11, and the heat transfer pipe 4A and the heat medium pipe 12A are integrally connected by ribs 30 corresponding to heat transfer fins. In addition, heat transfer pipe 4A
A plurality of heat transfer fins 4'A are provided on the outside of the heating medium pipe 12A, and a plurality of heat transfer fins 12' are provided on the outside of the heat medium pipe 12A.

In this embodiment, a nucleating agent 14 is attached to the surfaces of the heat transfer pipe 4A and the heat transfer fin 4'A that are inclined toward the auxiliary cooler, and this makes it possible to shorten the time until nucleation starts. The crystal growth of the heat storage material 2 is further promoted.

In this embodiment, a nucleating agent 14 is attached to the surfaces of a heat transfer pipe 4A and a heat transfer fin 4'A related to the auxiliary cooler, thereby shortening the time until the start of nucleation. The crystal growth of No. 2 is further promoted.

Next, still another embodiment of the present invention will be described with reference to FIGS. 6 and 7.

Here, FIG. 6 is a longitudinal sectional view of a heat storage section of a heat storage device according to still another embodiment of the present invention, and FIG. 7 is a sectional view taken along line AA' in FIG. 6. In the figure, the same reference numerals as in FIG. 2 are the same parts as in the above-described embodiment, so the explanation thereof will be omitted.

In the embodiment shown in FIG. 6, a heat transfer plate 15 is provided at the bottom of the heat storage tank 1 containing the heat storage material 2.
5, a heat transfer pipe 4B related to the auxiliary cooler and a heat medium pipe 12B related to the heater are arranged in a serpentine tube shape and brazed. This heat transfer plate 15 serves as each heat transfer fin in the embodiments shown in FIGS. 3 and 4.

Nucleating agent 14 is attached to the outer surfaces of heat transfer plate 15 and heat transfer pipe 4B.

FIG. 6 shows how hot water is flowed into the heat medium pipe 12B of the heater to melt the heat storage material crystal 2'. Since the heat medium pipe 12B is installed at the bottom of the heat storage tank 1, melting starts from the heat storage material 2 at the bottom. The melted lower heat storage material 2 causes convection and transfers heat to the upper heat storage material crystal 2' through the heat transfer plate 15 and the heat medium pipe 12B, so that the upper heat storage material crystal 2' also continues to gradually melt.

Next, an embodiment of the piping system of the refrigeration cycle will be described with reference to FIGS. 8 and 9.

8 and 9 are both schematic configuration diagrams of a heat storage device according to still another embodiment of the present invention, and in both figures, the same reference numerals as in FIG. Since the example is equivalent, its explanation will be omitted.

First, the embodiment shown in FIG. 8 will be explained.

In the embodiment shown in FIG. 1, after the refrigerant leaving the capillary tube 7 passes through the auxiliary cooler 4,
The structure was such that it entered the main cooler 3.

In contrast, in the embodiment shown in FIG. 8, the refrigerant pipe 8A is connected so that the refrigerant is introduced into the auxiliary cooler 4 after passing through the main cooler.

Even in this case, the same effect as the embodiment shown in FIG. 1 can be expected.

Next, in the embodiment shown in FIG. 9, the refrigerant pipe 8B is branched into two parts and connected in parallel to the main cooler 3 and the auxiliary cooler 4, so that the refrigerant can flow into both coolers at the same time. be.

The branch pipe 8B-1 connected to the main cooler 3 and the branch pipe 8B-2 connected to the auxiliary cooler 4 have valves 16-1 and 16-2 connected to the refrigerant flow control means, respectively.
2 is attached, but when heat is extracted from the heat storage material 2 by the main cooler 3 and the auxiliary cooler 4, the valves 16-1 and 16-2 are first opened, and the heat storage material crystal 2 is placed near the auxiliary cooler 4. ′ started growing,
Valve 16-2 can be closed to stop the flow of refrigerant in auxiliary cooler 4.

In this way, after the valve 16-2 is closed, the heat storage material crystals 2' on the four sides of the auxiliary cooler are not extremely cooled, and the temperature between the heat storage material crystals 2' in the lower layer and the main cooler 3 is reduced. The difference becomes large, and the convective heat transfer coefficient to the main cooler 3 becomes large. Valve 16-1,
16-2, first switch valve 16.
-1 and open the valve 16-2, and when the heat storage material crystal 2 grows in the auxiliary cooler 4, close the valve 16-1.
It is also possible to close 2.

Next, FIG. 10 is a schematic configuration diagram of a heat storage device according to still another embodiment of the present invention, and the same reference numerals as in FIG. 1 are equivalent parts to those in the embodiment of FIG. 1. Since there is, I will omit the explanation.

In the embodiment of FIG. 10, the heater is connected to two heat storage materials 2.
In addition to the heater 12-1 installed in the four auxiliary coolers as in each of the above-mentioned embodiments,
A heater 12-2 is also added to the third main cooler.

As a result, the same effects as those described in the embodiment of FIG. 1 can be expected, and the melting of the heat storage material 2 can be further accelerated.

In the above embodiment, the heat source of the heater that replenishes heat to the heat storage material is solar heat. However, the present invention is not limited to this, and the heat source that collects heat with the heat collecting means may be the residual heat of the boiler or the like. It goes without saying that it is also possible to use waste heat from a factory.

Similarly, in the above-mentioned embodiments, the example of indoor heating on the heat utilization side was explained, but the present invention is not limited to these, and can be used in various ways such as greenhouses, drying, and hot water supply.

〔Effect of the invention〕

As described above, according to the present invention, in a heat storage device using a coagulable heat storage material, the heat transfer efficiency of the main cooler in which the refrigerant of the refrigeration cycle should absorb heat of solidification by the heat storage material is determined by the temperature at which the heat storage material begins to crystallize. It remains in good condition even after
It is possible to provide a heat storage device that can be put to practical use and is highly profitable.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a heat storage device according to an embodiment of the present invention, FIG. 2 is a detailed diagram of the heat storage tank portion thereof,
3 is a three-dimensional perspective view of the auxiliary cooler and heater shown in FIG. 2, FIG. 4 is a perspective view of the auxiliary cooler and heater of the heat storage device according to another embodiment of the present invention, and FIG. The figure is a cross-sectional view of FIG. 4, FIG. 6 is a longitudinal cross-sectional view of a heat storage tank portion of a heat storage device according to another embodiment of the present invention, and FIG. 7 is a cross-sectional view taken along line A-A' in FIG. Figure, 8th
10 through 10 are all schematic configuration diagrams of a heat storage device according to still another embodiment of the present invention. 1... Heat storage tank, 2... Heat storage material, 2'... Heat storage material crystal,
3...Main cooler, 3'...Heat transfer fin, 4...Auxiliary cooler, 4A, 4B...Heat transfer pipe, 4'...Plate fin, 4A'...Heat transfer fin, 5...Radiator, 7...Capillary tube , 8, 8A, 8B...refrigerant piping,
9... Compressor, 11... Heat medium piping, 12, 12-1,
12-2... Heater, 12A, 12B... Heat medium pipe, 12'... Plate fin, 12'A... Heat transfer fin, 13... Heat collector, 14... Nucleating agent, 15... Heat exchanger plate, 16-, 16-2...Valve, 30...Rib.

Claims (1)

[Claims] 1. A coagulable heat storage material built into a heat storage tank, a first cooler disposed in the upper layer of the heat storage material, and a second cooling device disposed in the lower layer of the heat storage material. A heat storage device comprising: a nucleating agent provided in or near the second cooler; and a heater for replenishing heat to the heat storage material.