JPH10288360A - Heat storage device - Google Patents

Abstract

(57) [Summary] [Problem] An open-type heat storage device that connects a plurality of unit tanks.
The thermal storage efficiency is improved without breaking the temperature stratification state in the thermal storage device. SOLUTION: A return pipe from a heat exchanger is connected to each tank,
An electric valve is attached to each of the return pipes, and temperature indicating controllers 25 to 28 are attached in each tank. When the low-temperature cold water taken out of the low-temperature side tank hardly radiates heat in the heat exchanger and is returned at a low temperature, the system to return from the heat exchanger is changed by the temperature instruction controllers 25 to 28 in each tank. The temperature is controlled so as to return to the tank closest to the return temperature from the heat exchanger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a heat storage device.

[0002]

2. Description of the Related Art Generally, one of the desirable basic characteristics of a heat storage tank is that water having different temperatures is not mixed in the heat storage tank. For this purpose, heat storage tanks are classified into two types: completely mixed type, in which the heat storage tank is divided into a number of tanks, and cold water in each tank is completely mixed, and temperature stratified type, in which each tank maintains temperature stratification. There is a way heat storage tank.

Conventionally, among the open-type heat storage tanks, those using pipes in a communication system include a communication pipe system shown in FIG. 1 and a pipe induction system shown in FIG. FIG. 1A is a plan view of the communicating pipe system, and FIG. 1B is a ABC of the plan view shown in FIG.
The figure shows the -D-E-F sectional view. 2 (a) is a plan view of a pipe guiding method, and FIG. 2 (b) is a GHIJKL cross-sectional view of the plan view shown in FIG. 2 (a). The communication pipe method is a continuous perfect mixing type, and the pipe induction method is a temperature stratification type.

The communication pipe system is a method in which tanks are connected to each other by communication pipes 1 to 7 having a diameter of about 200 to 500 mm. In order to promote mixing of the tanks and reduce the amount of stagnation, the flow rate of the communication pipe section is increased. Also, plan the position so that there is no short-circuit flow. There is also a method of promoting mixing by inserting a device for stirring water in the tank. In the communication pipe system, the efficiency cannot be improved unless the number of tanks is more than ten. Moreover, although the water in each tank is completely mixed, the entire heat storage device can suppress the mixing of water by connecting many tanks in series.

[0005] In the pipe guiding method, communication pipes 8 to 10 connecting the tanks in the heat storage tank are erected and installed so that water is guided up and down in the heat storage tank so as to form a temperature stratified type. It was done. The temperature stratification type uses the difference in water density depending on the difference in temperature to store high-temperature, low-density water and low-temperature, high-density water without mixing as much as possible.
Use. Low-temperature cold water created by a refrigerator or the like at night is gently discharged into the tank through an opening provided near the bottom of the heat storage tank, and the high-temperature water already radiated by the heat exchanger of the air conditioner Move to slowly push up cold water. Due to the density difference between the two types of water having different temperatures, high-temperature cold water flows to the upper part and low-temperature cold water flows to the lower part. In order to form such a temperature stratification type, it is desirable that the temperature in the heat storage tank rapidly changes at a certain height, and it is necessary to suppress the mixing of water in each tank.

[0006]

Generally, one of the desirable basic characteristics of a heat storage tank is that water having different temperatures is not mixed as much as possible in the heat storage tank. In a thermal stratification type thermal storage tank, it is ideal to store heat without mixing as much as possible high-temperature, low-density water and low-temperature, high-density water by utilizing the difference in water density depending on the temperature. .
However, when returning the return water from the refrigerator or heat exchanger into the heat storage tank, the heat storage efficiency is reduced by mixing the water in the heat storage tank or mixing the high-temperature return water into the low-temperature tank. Let me do it.

In a heat exchanger of an air conditioner, even if the flow rate is increased above a certain flow rate, the increase in heat exchange capacity is reduced. Therefore, it is necessary to control the maximum flow rate in order to secure the difference between the inlet and outlet temperatures of the cold water. By reliably controlling the flow rate flowing through the heat exchanger and securing the temperature difference between the inlet and the outlet of the heat exchanger, the heat storage tank can be used effectively. However, if the flow rate cannot be sufficiently controlled by the heat exchanger, when the cooling load is small and the operation rate of the heat exchanger is low, the chilled water returns to the heat storage tank with the chilled water temperature hardly changing. The cold water on the low-temperature side of the heat storage tank returns to the high-temperature side with little heat radiation, and lowers the temperature in the high-temperature side heat storage tank. Since the refrigerator takes out water from the high-temperature side of the heat storage tank, the lower the temperature on the high-temperature side, the lower the efficiency of the refrigerator.

An object of the present invention is to return the cold water to the low-temperature side of the heat storage tank instead of the high-temperature side of the heat storage tank when the cooling load is small and the operation rate of the air conditioner is low and the temperature of the cold water hardly rises in the heat exchanger. The object of the present invention is to improve the heat storage efficiency by suppressing the mixing of water having different temperatures in the above.

[0009]

Means for Solving the Problems In order to solve the above-mentioned object, the present invention has taken the following means. That is, the configuration of the present invention is a heat storage device in which a plurality of unit tanks are connected in an open manner, a communication pipe connecting between the tanks is attached near a bottom surface of the heat storage device, and the communication pipe is arranged along a partition wall. Launch. When discharging the heated cold water returned from the heat exchanger into the heat storage device, the height fluctuates with the water surface in an arrangement where the cold water directly hits the straightening vanes to suppress the mixing of water in the heat storage device. Install a current plate. Conversely, when discharging low-temperature chilled water returning from the refrigerator into the heat storage device, a guide pipe from the upper part to the lower part of the heat storage device is installed, and the low-temperature chilled water is gently discharged from the lower part of the heat storage device. Make structure.

A return pipe from the heat exchanger is connected to each tank, an electric valve is attached to each return pipe, and a temperature indication controller is attached to each tank. When the low-temperature cold water taken out of the low-temperature side tank hardly radiates heat in the heat exchanger and is returned with the temperature kept low, the temperature return controller of each tank changes the system returning from the heat exchanger to the heat storage device, Control is performed so as to return to the tank closest to the return temperature from the heat exchanger.

[0011]

FIG. 3 to FIG. 6 show an embodiment of the present invention.
This will be described with reference to FIG.

FIG. 3 is a sectional view showing an embodiment of a heat storage device in which unit tanks from the water tank 11 to the water tank 14 are connected in a line. In the vicinity of the bottom of the connection part of the unit tank, a communication pipe 15 ~
In this case, a pipe-guiding method is used in which the pipe is raised along the partition walls 18 to 20 through the pipe 17 to provide a temperature stratified heat storage device. Outside the tank, a primary pump 30, a refrigerator, a secondary pump 29, and a heat exchanger are arranged. Each system is formed by water tanks at both ends, a chilled water circuit system 32 connected from the water tank 11 to the water tank 14, and a secondary circuit system 31. Aquarium 11
Temperature controller 25 from each to water tank 14
28 are attached, and by opening and closing the electric valves 21 to 24 of the secondary circuit system 31 branched from the water tank 11 to the water tank 14, it is possible to return the cold water from the secondary circuit system 31 to any tank. ing.

FIG. 4 shows a movable rectifying plate 37 attached to the discharge destination of the return water from the heat exchanger of the water tank 14 of FIG. A rectifying plate 37 is mounted on the water surface and moves with changes in the water surface. The high-temperature return water from the heat exchanger impinges on the rectifying plate 37 and spreads quietly on the water surface, thereby suppressing mixing with cold water in the water tank. Can be done. A hole is formed in the center of the current plate 37, and the support rod 3 is provided therein.
Since the number 6 is included, the movement in any direction other than the vertical direction is suppressed.

FIG. 5 is a view showing a guide pipe 39 provided at the outlet of the cold water return pipe 40 to which the water tank 11 shown in FIG. 1 is discharged to suppress mixing in the water tank. Although the cold water return pipe 40 is open above the water surface, mixing in the water tank can be suppressed by flowing to the bottom of the water tank via the guide pipe 39.

When storing heat, the electric valves 33 and 34 are opened, and the electric valve 3
5 is closed, the water taken out of the water tank 14 is cooled by a refrigerator, and returned to the water tank 11. The low-temperature cold water returned to the water tank 11 sinks to the bottom because of its high density, and pushes up the water that has entered before and flows into the water tank 12. The low-temperature cold water newly entering also in the water tank 12 sinks to the bottom. Thus, heat is stored in the heat storage device while maintaining the temperature stratified state.

Conversely, when heat is dissipated, the electric valve 35 is opened, and the electric valve 3 is opened.
3 and 34 are closed and the flow is the reverse of that during heat storage, and the low-temperature cold water taken out of the water tank 11 is radiated by the heat exchanger and returned to the water tank 14.

Basically, the heat storage device performs daytime air conditioning by using heat stored by cheap electric power at night. However, a chasing operation in the daytime is required due to the capacity of the heat storage tank and the like.
For example, when it becomes necessary to perform air conditioning at night, the heat storage operation and the heat radiation operation must be performed simultaneously. When the cooling load is small, the low-temperature cold water taken out of the water tank 11 is returned with almost no heat radiation in the heat exchanger. At this time, if low-temperature cold water is returned to the water tank 14, which is a high-temperature tank, the temperature of the water tank 14 decreases, so that the temperature at the inlet of the refrigerator decreases and the efficiency of the refrigerator decreases. Temperature indication controller 2 installed in each tank to prevent this
According to 5-28, return to the tank closest to the return temperature from the heat exchanger. As a result, it is possible to maintain the temperature stratified state of the entire heat storage device, and it is possible to improve the efficiency of the heat storage device and the refrigerator.

If the temperature in the heat storage device is not sufficiently lowered or if it is necessary to perform air conditioning rapidly, the motor-operated valve 35
, The electric valves 33 and 34 are closed, and the low-temperature chilled water cooled by the refrigerator is directly sent to the heat exchanger without returning to the heat storage tank, so that the inlet of the heat exchanger is used more than when the heat storage device is used. The temperature can be lowered. However, in this case, the circulation power of the pump is increased because the circulation path of the cold water is open.

FIG. 6 is a cross-sectional view of an embodiment in which an open circuit system for performing air conditioning by a heat storage device and a closed circuit system for performing air conditioning by a refrigerator are separately prepared when the heat exchanger has a large head.

When the motor-operated valves 41, 44 to 46, 48 are opened and the motor-operated valves 42, 43, 47, 49 are closed, the heat exchanger 51
Has a closed circuit with the refrigerator, and the heat exchanger 52 has an open circuit with the heat storage device. Since the heat exchanger 51 side has a closed circuit, the air conditioning on the higher floor can be performed with less transfer power than the heat exchanger 52.

[0021]

According to the present invention, the heat storage device suppresses the mixing of water having different temperatures in the heat storage device by changing the return piping system from the air conditioner by the electric valve and the temperature instruction controller. It is possible to maintain a temperature stratified state. Therefore, the effective volume of the heat storage device can be increased, and the efficiency of the heat storage device can be improved. In addition, since the temperature is in a stratified state, the highest temperature water in the heat storage device is always sent to the refrigerator, thereby enabling efficient operation of the refrigerator.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a communication pipe type as a conventional technique.

FIG. 2 is an explanatory view showing a conventional pipe guiding type.

FIG. 3 is an explanatory view showing an embodiment of the heat storage device of the present invention.

FIG. 4 is an explanatory view showing a rectifier for receiving return water from an air conditioner of the present invention.

FIG. 5 is an explanatory diagram showing a guide pipe for guiding return water from the refrigerator of the present invention to a lower part of the water tank.

FIG. 6 is an explanatory diagram showing an embodiment of an open / closed system in the heat storage device of the present invention.

[Explanation of symbols]

15-17: communication pipe, 11-14: water tank, 18-20 ...
Partition walls, 21 to 24, 33, 35 ... electric valves, 25 to 25
28: temperature instruction controller, 29, 30: pump, 3
1 ... secondary circuit system, 32 ... chilled water circuit system.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tetsuya Yamashita 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Information and Communication Business Division, Hitachi, Ltd. (72) Iku Fujiwara Iku 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Hitachi, Ltd. Information and Communication Division

Claims (5)

[Claims] 1. A heat storage tank for temporarily storing the heat of cold water and hot water, wherein the heat storage tank is a continuous type composed of a large number of tanks partitioned by walls, wherein the temperature of the cold / hot water in the heat storage tank is lower than the temperature. With a structure that circulates heat and dissipates heat while forming a stratified structure,
A heat storage device, comprising: a piping system that returns cold water to the low-temperature side of the heat storage tank instead of returning to the high-temperature side when the temperature of the cold water taken out of the low-temperature side tank does not rise in the heat exchanger. 2. The heat storage device according to claim 1, further comprising a piping system for returning the hot water to the high temperature side of the heat storage tank when the temperature of the hot water taken out of the high temperature side tank does not decrease in the heat exchanger. . 3. A structure in which return pipes to respective tanks constituting the heat storage tank are provided, and a return pipe system can be changed according to a return water temperature, and cool water or hot water is returned to a tank closest to the return water temperature. The heat storage device according to claim 1, wherein the heat storage device is controlled as follows. 4. When the heated cold water returning from the heat exchanger is discharged to the heat storage tank, the cold water is supplied to the rectifying plate whose height varies with the water surface in order to suppress mixing of water in the heat storage tank. 2. A heat stratification state in the heat storage tank is maintained without directly agitating the inside of the heat storage tank by returning cold water being directly applied to the flow straightening plate by installing the cooling water directly in the heat storage tank. A heat storage device according to claim 1. 5. An induction pipe from an upper part to a lower part in the heat storage tank to suppress mixing of water in the heat storage tank when discharging low-temperature cold water that has exited the refrigerator during the heat storage to the heat storage tank. 2. The heat storage device according to claim 1, wherein the heat storage device is installed to maintain a temperature stratified state in the heat storage tank by gently discharging cold water from the lower part of the heat storage tank through the guide tube. 3.