KR100469557B1 - Self Energy Storage System - Google Patents

Abstract

The present invention relates to a high-density natural heat storage device using latent heat of a phase change material, and does not use an artificial heat source such as a freezer, so that selective natural heat storage of hot or cold heat from ambient environment such as temperature difference between day and night is possible. It is possible. According to the present invention, heat or cold heat is spontaneously formed into a heat storage material made of a phase change material through a wall surface of a heat storage container having a temperature difference between the inside and the outside by limiting the heat transfer direction to a certain direction. .

Description

Natural Heat Storage Device {Self Energy Storage System}

The present invention relates to a high-density natural heat storage device using latent heat of phase change material, and in particular, it is possible to selectively heat or cool heat from the surrounding environment where temperature changes exist such as day and night temperature differences without using a separate heat source or device. It relates to a natural heat storage device capable of natural heat storage.

Recently, the necessity of heat storage technology is rapidly increasing in connection with load leveling of electric power. In recent years, capacity generation and nuclear power generation, which are difficult to operate by load-following type, are increasing, and the rapid increase in cooling demand in summer due to industrial development and improvement of national income is the main cause of inefficient operation of power generation facilities. have.

In order to control the load of the power generation facilities, the air-cooled cooling system operates the refrigerator during the late-night hours when the electric power demand is relatively low to accumulate the cooling heat, and during the daytime, it uses the cooling heat stored in the mid-night to cool the day-time cooling power demand. Can be reduced. In particular, the ice heat storage system enables the high-density latent heat storage by operating the freezer during the night time to make water into ice. At this time, the amount of latent heat of water is about 80 kcal / kg, and since the latent heat at the time of solid-liquid phase change at 0 ° C. is much higher than that of other materials, the heat storage density is high, thereby minimizing the capacity of the heat storage tank. However, if the temperature to be used is lower or higher than the phase change temperature of water, 0 ° C, a suitable phase change material having a suitable phase change temperature should be used as the heat storage material.

The current state of the heat storage technology using phase change materials is the latent heat storage type hot water and heating boilers, heat storage air conditioning, waste heat recovery, floor heating, greenhouse heating and insulation materials as a building material, and various refrigeration and Frozen food storage, and the like. In this case, organic materials and inorganic materials having suitable phase change temperatures other than water are used as heat storage materials.

Recent applications for phase change material heat storage technology include cooling systems in base stations and repeaters for mobile and optical communications. Base stations and repeaters installed in accordance with the rapidly increasing demands of various communication means in the world are increasing the heat generation density of equipment due to high performance and high integration, and the installation places are residential, building, mountain and desert according to their purpose. Because of the variety, the choice of cooling system also has many limitations.

Since the communication industry requires high reliability, durability of the refrigerator becomes a problem when the refrigerator is continuously operated for a long time for cooling the device. The refrigeration system using the freezer is not easy to supply electricity especially when the installation place is in the mountains or deserts, and it is difficult to cope within a short time because the freezer is not easily accessible. If the place of installation is a residential area, the residents will be inconvenienced by the noise of the freezer.

As an alternative to this problem, a conventional air-conditioning cooling system using a heat storage material having a suitable phase change temperature as shown in Figures 1 and 2 has been introduced.

This system is a shelter-type cooling system, and FIG. 1 shows a situation during night heat storage operation. At night, a relatively low temperature outside air 1 is attracted to the fan 2 so that a phase change material, that is, heat storage material 3 Cool it and store cold heat in latent heat form. Even during this heat storage operation, a part of the cold air 7 from the heat storage material 3 is used for cooling the electronic device 4, but at night, the hot air 5 from the electronic device 4 due to a relatively small load is applied. ) Is also small.

Therefore, even if the amount of cold heat absorbed by the heat storage material 3 from the low temperature outside air 1 cools the hot air 5 from the electronic device 4, the extra cold heat remains. This extra cold heat cools the heat storage material 3 to solidify it into a solid and store it in latent heat form.

FIG. 2 shows the situation during the daytime heat dissipation operation. In the daytime when the temperature of the outside air is relatively high, the operation of the fan 2 is stopped and the heat generation electronic device 4 is used by using the cold heat stored in the heat storage material 3 during the night. To cool. In this case, since a large amount of hot air 5 is generated from the electronic device 4 and there is no introduction of cold heat from the outside air, the cold heat 7 stored in the heat storage material 3 is used a lot to cool the electronic device 4. Ash 3 is melted and phase-changed into a liquid state.

When it is night again, the situation as shown in FIG. 1 is repeated to accumulate cold heat. This creates a refrigeration-free cooling system to cool the electronics.

In such a system, a paraffin-based organic material having a high-liquid phase change temperature of about 40 ° C is employed as a heat storage material in consideration of the operating limit temperature of a typical electronic component of about 65 ° C to about 90 ° C. This system is more effective when the temperature difference between day and night is large, such as in the mountains and deserts, and because it does not use a freezer, it is a highly reliable and economical energy-saving cooling system.

However, the natural air conditioning cooling system having a shelter structure has a limitation in the heat storage amount, and thus, there is a limit to the application to a high capacity repeater cooling system having a large amount of heat generation in recent years. Especially, in the case of residential area where the temperature difference between day and night is relatively small, the limit is remarkable.

In addition, there is a disadvantage that the electric drive fan (2) for the introduction of low-temperature outdoor air at the time of heat storage is necessary. In addition, after the end of the heat storage of the cold heat is not a special insulation device is a disadvantage that the heat loss from the heat storage material is large.

The present invention devised to solve the above problems is possible to heat storage by natural convection heat transfer of the atmosphere by using a feature that can limit the heat transfer direction of the wall structure of the heat storage material container without the need of an electric drive fan. The purpose of the present invention is to provide a natural heat storage device in which cold heat or heat heat can be selectively stored.

1 is a schematic diagram of the night heat storage operation of the conventional repeater cooling system

Figure 2 is a schematic diagram of the daytime heat radiation operation of the conventional repeater cooling system

3a and 3b is a bird's eye view and a cross-sectional view of the basic unit of the natural heat storage device according to the present invention

4a and 4b is an enlarged view of the wall structure of the heat storage container according to the present invention

5a to 5c are enlarged views showing the diaphragm shape according to the present invention

6a and 6b are a schematic view and a cross-sectional view of the natural heat storage device according to the present invention

7A and 7B are schematic diagrams connecting the basic units of the natural heat storage device according to the present invention in parallel and in series

<Explanation of symbols for main parts of drawing>

8: heat storage container 9: heat storage material

10: refrigerant flow path 11: refrigerant flow

12 wall structure 13 insulation

14: inner wall 15: outer wall

16: air 17: diaphragm

18: gravity direction 19: outer wall pin

The present invention for achieving the above object includes a heat storage container having a wall structure that can control the heat transfer direction and the heat transfer amount, and a heat storage material filled with a phase change material at a suitable temperature inside the heat storage container. In addition, the refrigerant flow path may further include a refrigerant flow channel through which the refrigerant flows.

3A and 3B show a bird's eye view (perspective view) and a cross-sectional view of the basic unit of the natural heat storage device of the present invention.

3A is a perspective view of the basic unit of the natural heat storage device, and the heat storage container 8 is filled with a heat storage material 9 that changes phase at a suitable temperature. In the present invention, considering that the operating limit temperature of a typical electronic component is about 65 to 90 ° C, and considering the local average temperature, a paraffinic organic material having a solid-liquid phase change temperature of 36.4 ° C and a heat of fusion of 247kJ / kg A substance (C ₂₀ H ₄₂ ) or the like may be used as the heat storage material. Solid-liquid and solid-gas phase change materials can also be used. The heat storage material 9 may be mixed with powders or particles such as metals having good thermal conductivity to improve heat transfer performance of the heat storage material space.

On the other hand, in the heat storage material (9) filling space inside the heat storage container (8) is installed so that the independent refrigerant flow path (10) penetrates to transfer the heat stored in the refrigerant flow (11) to the required place in the cooling system to use the cold heat It may be.

3B is a basic unit cross-sectional view of the natural heat storage device, in which the wall structure 12 of the heat storage container 8 is configured as a parallelogram-shaped closed space to restrict the heat transfer direction only in a predetermined direction, thereby accumulating heat from the surroundings where temperature changes exist. Desired heat storage (heat or cold heat) to ash 9 takes place on its own.

Here, the wall structure 12 is for the heat storage only cold heat. The wall structure of the side wall 12 of the container 8 basically consists of a double wall, and an inclined diaphragm 17 is provided therebetween to form a parallelogram-closed space. Here, the upper and lower walls 13 of the container are filled with a heat insulating material. That is, the natural heat storage device of the present invention connects the upper wall 13 and the lower wall 13 filled with the insulation and the edges of the upper wall 13 and the lower wall 13 to form a phase change material 9. A plurality of inclined walls between the inner sidewalls 14 forming the received inner space, the outer sidewalls 12 arranged to be spaced apart from the inner sidewalls by a predetermined distance, and the plurality of sidewalls 12. It consists of a plurality of diaphragms 17 arranged to form a closed space, and a phase change material 9 accommodated in the inner space formed by the inner wall.

4A and 4B are detailed views of an enclosed space of one wall structure, wherein air 16 in the enclosed space flows in a natural convection phenomenon caused by a temperature difference between the inside and the outside of the wall, and the air flow 16 is enclosed. The inclination angle of the diaphragm 17 of the space and the temperature distribution of the inner and outer walls 14 and 15 are determined. Here, the upper and lower wall surfaces (not shown) of the heat storage container 8 are filled with a heat insulating material.

4A shows a wall structure in which the temperature of the heat storage material is higher than the temperature of the outside air, when the gravity direction 18 faces downward and the temperature inside the container filled with the heat storage material 9 is higher than the temperature of the outside air. The hot air absorbs heat from the inner wall 14 of the high temperature, and the lightened air moves smoothly to the outer wall 15 of the low temperature along the wall surface of the diaphragm 17 which is inclined upward, thereby releasing heat. The cool air, which releases heat from the cold outer wall 15 and cools, moves smoothly back to the hot inner wall 14 along the wall surface of the downwardly inclined diaphragm 17. At this time, the heat transferred to the outer wall 15 is cooled by the natural convection of the outside air and dissipated to the atmosphere. Thus, the air 16 between the double plates promotes heat transfer to the outside through the inner and outer walls 14 and 15 while continuously circulating in the confined space in natural convection, so that the temperature of the heat storage material 9 is lowered and the heat is accumulated. When the phase change temperature of the ash (9) is below, the heat storage material (9) solidifies and stores cold heat as latent heat. By adjusting the inclination angle of the diaphragm 17, the amount of heat transfer can be controlled.

4B is a heat storage vessel wall structure when the temperature of the heat storage material is lower than the temperature of the outside air, and the air 16, which is lightened by absorbing heat from the high temperature outer wall 15, rises along the high temperature outer wall 15, In short, it collides with the downwardly inclined diaphragm 17 and descends to form a recirculating flow only near the hot wall surface 15. Similarly, the cold and heavy air 16 in the low temperature inner wall 14 descends along the low temperature wall surface 14, but soon collides with the upwardly inclined diaphragm 17 and only near the low temperature inner wall 14. To form a recirculating flow. At this time, the air 16 in the large central part in the sealed space is almost in a stagnant state.

Inherently flowless air transfers heat only by conduction, so air with a low coefficient of thermal conductivity of around 0.026 acts as a good thermal insulation layer. Therefore, the heat from the high temperature outside air is blocked from being transferred to the low temperature interior.

The wall structure such as the double sidewall 12 of the heat storage container 8 can be applied to the waste heat recovery of the heat insulation of the various heat insulation wall surface and plant process because it can limit the direction of heat transfer and control the amount of heat transfer.

The arrangement of the diaphragms 17 as shown in FIG. 3b in the present invention allows heat transfer only from the inside filled with the heat storage material 9 to the outside air and restricts the heat transfer direction to block heat transfer from the outside air to the internal heat storage material 9. can do. In other words, if the height of the portion close to the outer wall 15 is formed to be higher than the height of the portion close to the inner wall 14, the sealed space formed by the diaphragm 17, as shown in Figure 4a If the temperature is high and the temperature of the outer wall 15 is low, heat is transferred from the inner wall 14 to the outer wall 15 due to the convection of air 16 in contact with the inner wall 14 and the outer wall 15. As shown in FIG. 4B, when the temperature of the inner wall 14 is low and the temperature of the outer wall 15 is high, the air 16 is convex in the form of circulation in the vicinity of the inner wall 14 and the outer wall 15. Heat transfer from the outer wall 15 to the inner wall 14 is blocked. Therefore, only cold heat is always stored in the heat storage container even if there is a temperature change of the outside air. When the heat storage material is filled in the heat storage container having a double sidewall 12 wall structure and installed in the air, the heat storage material in the container releases heat to outside air at low temperature and coagulates and stores cold heat in latent heat form during the day. It can be used as an ideal cold heat storage device by blocking the intrusion of heat from high temperature outside air.

On the other hand, when the inclination direction of the diaphragm 17 between the double wall surface of the container is installed in the opposite direction to FIG. 3B, heat from the outside air is well transmitted to the inside, but excellent heat is generated by blocking the release of heat from the inside of the container to the outside air. It can be used as a heat storage device.

The naturally regenerated heat can be extracted as needed using the refrigerant flow 11 flowing through the refrigerant flow passage 10 independently installed to penetrate the heat storage container, and used as a heat source for cooling and heating.

5a to 5c show the shape of the diaphragm of the present invention, and the various design of the diaphragm 17 in the double partition 12 wall structure of the heat storage container 8 provides excellent heat transfer direction limiting performance and a desired degree of heat transfer. Can be designed to work.

6a and 6b show a schematic view and a cross-sectional view of the natural heat storage device of the present invention.

Figure 6a is a schematic diagram of a natural heat storage device, by installing the outer wall fins 19 of various shapes on the outer wall of the heat storage container (8) filled with the phase change material to maximize the heat transfer by natural convection of the outside air to facilitate heat transfer It can be done.

6B is a cross-sectional view of the natural heat storage device, wherein the inner wall of the heat storage container 8 filled with the phase change material 9 has a fin-shaped structure 20, or a porous foam structure made of a metal having excellent thermal conductivity, and a spring shape. The heat transfer performance in the heat storage material 9 can be improved by introducing a structure, a mesh-shaped structure, or the like.

7A and 7B are schematic diagrams in which the basic units of the natural heat storage device of the present invention are connected in parallel and in series, in which case a plurality of heat storage containers 8 of the basic unit are connected in parallel or in series to require a large heat dissipation performance. Can be used for

According to another embodiment of the present invention, a fan is installed outside the natural heat storage device as shown in FIGS. 7A and 7B and used as a heat transfer promoting mechanism to outside air, if necessary.

As described above, the natural heat storage device of the present invention can be used as an ideal natural heat storage device in which cold heat or heat is selected and stored naturally without using a separate energy consumption mechanism in various environments such as daytime and night temperature. Can be. In addition, the wall structure of the heat storage container that can limit the direction of heat transfer and control the heat transfer amount has an advantage that can be applied to the waste heat recovery of the heat insulation of the various thermal insulation wall and plant process.

Claims (10)

An upper wall filled with insulation, A bottom wall filled with insulation, A double side wall including an inner wall connecting the edges of the upper wall and the lower wall to form an inner space, and an outer wall disposed to be spaced apart from the inner wall by a predetermined distance; A plurality of diaphragms arranged to form a plurality of inclined sealed spaces between the double sidewalls; And a phase change material contained in the inner space formed by the inner wall. The method of claim 1, The plurality of inclined sealed spaces, the natural heat storage device, characterized in that the height of the portion close to the outer wall is formed higher than the height of the portion close to the inner wall. The method of claim 2, The inclined closed space is a natural heat storage device, characterized in that the parallelogram shape. The method according to any one of claims 1 to 3, The natural heat storage device further comprises a refrigerant flow channel inserted through the upper wall and the lower wall of the container. The method of claim 4, wherein And a plurality of fins fixed to protrude outward from the outer wall. The method of claim 5, And a plurality of fins fixed to protrude inwardly to the inner wall. delete delete delete delete