JPS6226432A - Ice heat storage vessel - Google Patents

Abstract

PURPOSE:To provide a highly efficient ice heat storage vessel of a compact structure and a small motive power of a freezer by inserting a cylindrical container full of water into a vessel having a heat insulative property and filled with an antifreezing solution and to make it possible to supply power to water within the container by use of two electrodes connected to a power supply device. CONSTITUTION:A vessel 12 having a heat insulative property is filled with an antifreezing solution 14. A number of bottomed cylindrical containers 16 in which is placed water as a coolness storage agent are inserted perpendicularly into a vessel 12, and fixed to the cover of the vessel 12. A bar-like electrode 18 is inserted into water within each of containers, and the electrodes are divided into three systems in accordance with the flow direction of the antifreezing solution within the vessel 12 and connected to a power supply device 24 through switches 22. The container 16 itself made of a conductive material constitutes a second electrode 20, and is connected to the ground side of the power supply device 24. Thus, since the ice making rate can be increased, the quantity of heat escaping to the circumference is reduced.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention operates a refrigerator to cool water in a heat storage tank.
The present invention relates to an ice heat storage tank for an air conditioning system that performs air conditioning using the obtained cold water and ice.

2. Description of the Related Art Air conditioning systems that operate a refrigerator using nighttime electricity, store cold water and ice in a heat storage tank, and use this to cool the living room are already well known. In this air conditioning system, the refrigerant (or brine) from the refrigerator is introduced into the heat storage tank through a pipe, and the refrigerant (or brine) pipe is arranged in a coiled or U-shaped meandering shape to function as a cooler. It has a cooling device in the heat storage tank in which the cold K (or si-line) that has passed through the cooler is returned to the refrigerator again. In this heat storage tank cooling device, a cooler is fixed in a heat storage tank, and ice is formed on the outer surface of the cooler using a refrigerant from a refrigerator, so that ice and water coexist in the heat storage tank. This air conditioning system circulates the cold heat stored by the ice and water to the air conditioner via piping as cold water.

This air conditioning system uses not only cold water but also the latent heat of melting ice, so the heat storage capacity of the heat storage tank is increased, and as a result, there is an advantage that the heat storage tank can be made compact. However, in conventional ice storage tanks, the heat exchanger tubes (
Since ice is growing on the outer surface of the refrigerant (or brine pipe), thermal resistance increases significantly as the ice grows, and the fluid temperature inside the heat transfer tubes has to be further lowered, which increases the power consumption of the refrigerator. There was a point. Also, ice formed in the cooler grows at a constant rate until it reaches a certain thickness, but 2
When the thickness reaches 0 to 30 mm, the cooling capacity of the cooler decreases, resulting in a significant decrease in ice growth. Therefore, in order to increase the amount of ice produced, it is necessary to periodically remove the ice adhering to the cooler, which requires operations such as switching the refrigerator to the defrost cycle (defrosting), which significantly reduces the movement of the heat storage tank. There was a drawback. Furthermore, since it is not possible to increase the amount of heat transfer tubes that can be immersed in the tank, it is not possible to increase the ice making rate of the water in the tank. On the other hand, if the number of heat transfer tubes in the tank is too large or the ice making rate is increased to 50% or more, the fluidity of the water in the tank deteriorates, causing problems such as the inability to extract cold heat. Therefore, in the conventional technology, the ice making rate was limited to 30%.

Problems to be Solved by the Invention An object of the present invention is to provide a highly efficient ice heat storage tank that is more compact than conventional ice storage tanks and consumes less power of the refrigerator.

Means for Solving Problems and Their Effects The above-mentioned object of the present invention is to store antifreeze in a tank having heat insulation properties, and to insert a cylindrical container filled with water into the tank filled with antifreeze. This is accomplished by an ice storage tank in which the water in the container can be energized using two electrodes connected to a power supply.

Preferably, two electrodes are inserted into the container, but it is also possible to make the container of a conductive material and insert only the first electrode into the water within the container, with the container itself serving as the second electrode. This simplifies the electrode configuration and reduces costs.

According to the above configuration, the antifreeze is cooled by the refrigerator, and the water in the container can be turned into ice to store cold.

Conventionally, when cooling water in such a container,
It was known that a supercooling phenomenon occurs and ice does not form even when the temperature drops to about 15°C. In the present invention, if the water temperature inside the container does not freeze even if it falls below 0°C, the supercooling state is canceled by turning on the power supply switch and energizing, and ice is forced into the container. The feature is that it is generated. In a container, plate-shaped ice forms all over the water as soon as electricity is applied, and the ice continues to grow from the outside of the tube toward the center, resulting in excellent heat transfer properties, and the water inside the container almost completely turns into ice. Since the antifreeze flows through the gaps outside the container, there is no decrease in fluidity due to ice growth, and the evaporation temperature of the refrigerator can be maintained higher than that of conventional ice storage tanks, reducing the power consumption of the refrigerator. less. Since the container may be a simple cylindrical shape, it is possible to insert a large number of containers into the heat storage tank to increase the packing density and increase the ice making rate. Therefore, the heat storage tank can be made even more compact. Since the shape of the container is simple and it is sufficient to mass-produce containers of the same shape, there is no cost problem.

Other characteristics and advantages of the invention will become apparent from the following description with reference to the embodiments of the accompanying drawings.

Embodiment FIG. 1 shows an example of an air conditioning system including an ice heat storage tank 10 according to the present invention. Inside the tank 12 is a bottomed cylindrical container 1 containing water as a cold storage agent.
6 are inserted vertically and fixed to a cover (not shown) of the tank 12. In this embodiment, the circuit for the antifreeze 14 is an open circuit, and the mouth of the container 16 projects above the level of the antifreeze. One rod-shaped electrode 18 is inserted into the water in each container, divided into three systems depending on the flow direction of the antifreeze in the tank, and connected to a power supply device 24 via a switch 22. The container 16 itself made of conductive material constitutes the second electrode 20 and is connected to the ground side of the power supply 24 .

The antifreeze liquid 14 is sent to the refrigerator 28 by the operation of the pump 26, and after being cooled, it is returned to the tank.

The refrigerator 28 includes a compressor a1 a condenser b1 an expansion valve C1 an evaporator d
Contains.

The air conditioner 30 and other loads are connected to the secondary circuit of the air conditioning system, and the antifreeze cooled in the water heat storage tank is pumped to the pump 32.
It is circulated by the air to perform a cooling effect.

The air conditioning system including the ice heat storage tank 10 according to the present invention is configured as described above, and the antifreeze 14 cooled by the action of the refrigerator 28 cools the container 16.
The water inside 6 is cooled from the outside and when it reaches OoC, it starts to freeze or becomes supercooled and the water temperature further decreases. If it becomes supercooled, turn the switch 22 to O.
Turn on N and energize the water to release the supercooled state. As a result, the water in the container 16 begins to freeze, and eventually becomes completely frozen. Even if the water in the container completely freezes, it does not affect the fluidity of the antifreeze, so it can start flowing to the secondary side.

It is preferable that the switch 22 divides the electrodes into a plurality of systems depending on the flow direction of the antifreeze and the electric capacity, and performs ON-OFF operation. The power source can be either alternating current or direct current.

In Figure 2, the antifreeze 14 circuit is a closed circuit.

The figure shows an embodiment in which a number of containers 16 containing water extend below the bottom of the tank 12. Two rod-shaped electrodes 40.degree. 42 are inserted into each container 16. As a modified example, a water tank 4 is placed below the container 16.
4, and the bottom of each container can be connected to a water tank 44 for communication. By providing such a communicating water tank 44, the height of the water surface inside the container can be kept constant.
An advantage is that there is no need to adjust the amount of water in each container.

In the example shown in FIG. 2, a heat exchanger 46 is inserted into the secondary circuit, and water is circulated to the air conditioner 30 by operation of a pump 48.

Generally, heat storage tanks are installed underground in buildings and are operated at night, so it is not easy to confirm whether supercooling is occurring inside the container. Therefore,
A sensor detects the water temperature in the container or in the antifreeze liquid, and when the water temperature falls below 00C, it is assumed that the water in the container is in a supercooled state, and the switch 22 is automatically turned off intermittently.
It is preferable to carry out automatic control such that the N-OFF operation is performed.

The effects when the ice heat storage tank according to the present invention is applied to an actual building are as follows. If a heat storage tank is installed in a building with a total floor area of 10,000 m2 and a maximum cooling load of 300 refrigeration tons, and the chiller capacity is reduced to 150 refrigeration tons, the required volume of the heat storage tank will be as follows.

1) Ice production rate of 60% using ice heat storage tank (this invention) 54m32
) Ice production rate 30% with ice heat storage tank (conventional) 100m33)
For water heat storage tank: 6oOm3 volume: 54
The annual operating cost of the refrigerator when a water heat storage tank of m is installed is 100 without a heat storage tank, and the ice making rate is 30% (
It is 86% in the case of the conventional method and 75% in the case of the ice making ratio of 60% (the present invention). This is because you can take advantage of cheaper electricity rates at night.

Effects of the Invention As explained in detail above, according to the present invention, the ice making rate can be increased compared to the conventional method, the water heat storage tank becomes compact, and the amount of heat escaping to the surroundings is reduced, so that the occlusion efficiency is increased. Since the liquid in the tank always maintains fluidity, the evaporation temperature of the refrigerator can be maintained higher than before, and the power consumption of the refrigerator is reduced, which is extremely effective. There is something.

[Brief explanation of drawings]

FIG. 1 is a system diagram of an air conditioning system including an ice heat storage tank according to the present invention, and FIG. 2 is a system diagram showing another embodiment of the air conditioning system and water heat storage tank.

Claims (1)

[Claims] 1. Antifreeze is stored in a tank with heat insulation properties, a cylindrical container filled with water is inserted into the tank filled with antifreeze, and two electrodes connected to a power supply are used. An ice heat storage tank characterized in that the water in the container can be energized by the water in the container. 2. The ice heat storage tank according to claim 1, wherein two electrodes are inserted into the water in the container. 3. The ice storage tank according to claim 1, wherein the container is made of a conductive material, the first electrode is inserted into the water within the container, and the second electrode is the container itself.