JPS58117937A - Coldness heat accumulator - Google Patents

Abstract

PURPOSE:To enhance coldness heat-accumulating efficiency, by a method wherein a cooler is provided in a coldness heat-accumulating water tank, and the temperature of a refrigerant supplied is repeatedly changed over between an ice- making temperature and a defreezing temperature, in a coldness heat-accumulating water tank for heat-pump air conditioning with water used as a heat source. CONSTITUTION:When supplying a refrigerant to the cooler 2 by a pump 11, three-way valves 7, 8 are changed over to cyclically provide a low-temperature refrigerant circuit and a high-temperature refrigerant circuit with a predetermined period, wherein the low-temperature refrigerant circuit is comprised of a low- temperature refrigerant tank 3 pipes (a), (b) the cooler 2 pipes (c), (d) a high-temperature refrigerant tank 4, while the high-temperature refrigerant circuit is comprised of the tank 4 pipes (e), (b) the cooler 2 pipes (c), (f) the tank 3. With this constitution, freezing and defreezing take place repeatedly on the surface of the cooler 2, so that ice is released from the cooler 2 and is floated in cooling water. Accordingly, the cold heat-accumulating efficiency can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat storage water tank used in air conditioning equipment using a water heat source heat pump, and more particularly to a cold heat storage device useful for storing cold heat for use in air conditioning.

When storing cold heat in a heat storage water tank, a large amount of cold heat can be stored in a small water tank by converting a portion of the cold water into ice and storing the cold in the form of sensible heat and latent heat by making water and ice coexist. In this case, it is convenient to install a cooler such as a cooling pipe or a cooler in the heat storage water tank, and to flow a refrigerant below the freezing point into the cooler to make ice on the surface of the cooler Ic.

However, when making VC ice on the surface of the cooler, the growth rate of the ice is fast at the beginning of cooling, but gradually slows down as the ice grows, and the ice formed on the surface of the cooler becomes thicker. As the temperature increases, heat transfer resistance increases and ice making efficiency decreases. As a result, both the heat storage efficiency and the refrigerator efficiency are reduced by V.

The present invention was made with the aim of solving this problem, and has developed a cold heat storage device t that can store cold heat extremely efficiently.

The device of the present invention will be explained according to the drawings. FIG.
This is a device in which a cooler 2 is installed in a heat storage water tank 1, and a part of the cold water is made into ice on the surface of the cooler 10, and the temperature of the refrigerant supplied to this cooler 11L is the ice-making temperature. This figure systematically shows the arrangement of the cold heat storage device according to the present invention in which the temperature and the melting temperature are alternately repeated.

In FIG. 1, 3 is a low temperature refrigerant tank, 4 is a high temperature refrigerant tank, 5 is a refrigerator, 6 is a cooler, and 7 and 8 are 60,000 valves. The low-temperature refrigerant tank 5 and the high-temperature refrigerant tank 4 contain the same refrigerant, for example, a 40-thiethylene glycol aqueous solution, and the low-temperature refrigerant tank 3Vc contains the refrigerator brine l'
(A heat exchanger 9 is installed to maintain the refrigerant temperature at approximately -20 to -5 ar:vc, and the other high-temperature refrigerant tank 4 is a heat exchanger through which chiller cooling water (high temperature side) flows. 10 is installed so that the refrigerant temperature is maintained at about 3 ocvc.Hereinafter, the former low-temperature refrigerant will be referred to as the low-temperature refrigerant, and the latter high-temperature refrigerant will be referred to as the high-temperature refrigerant.

The device of the present invention alternately supplies this low-temperature refrigerant and high-temperature refrigerant to the cooler 2.
It is characterized by the fact that it allows liquid to flow through it, which significantly increases ice-making efficiency. That is, when supplying refrigerant to the cooler 2 by opening the port 11, by switching the three-way valves 7 and 8, the low temperature refrigerant tank 6, - Pipe A - Pipe S - Cooler 3 - Pipe C - Pipe d - A low temperature refrigerant circuit that passes through the route of high temperature refrigerant tank 4, and a route of high temperature refrigerant tank 4 - Pipe e - Pipe 2 - Cooler 2 - Pipe C - Pipe f - Low temperature refrigerant tank 6. The high-temperature refrigerant circuit and the high-temperature refrigerant circuit are switched under a predetermined time cycle, and ice of a predetermined thickness is formed on the surface of the cooler 2 by operating the low-temperature refrigerant circuit for a predetermined time (for example, 5 minutes). By operating the high-temperature refrigerant circuit, part of the ice adhering to the surface of the cooler 2 is melted, thereby cutting the edge between the cooler 2 and the ice, and the edge is cut and the nine pieces of ice are suspended in the cold water. The cycle of doing so is repeated. If the cooler 2 is installed below the heat storage water tank 1, ice will float to the top of the tank due to the difference in specific gravity during this ice-melting operation. The operation time of the high-temperature refrigerant circuit can be made equal to the operation time of the low-temperature refrigerant circuit, but the operation time may be longer or shorter depending on the equipment used. The setting and switching of this operating time can be done by the timer 15VC.

Figure 2 is a relationship diagram showing all the ice making speeds when using a flat plate cooler. For example, when the refrigerant temperature is -20C, the thickness of the ice increases rapidly for about 5 minutes after the start of ice making. However, after that, the growth rate decreases with the passage of time (7
, Even after continuing ice making operation for about 60 minutes, the ice thickness remains F'15 cm.
I can't stand it. Therefore, for example, if ice-making operation and ice-melting operation are performed alternately for 5 minutes each for a total of 60 minutes, each ice-making operation will produce ice with a thickness of approximately 0.8 to 0.9 cm. 9.6 to 10.12 times.
It is understood that ice having a thickness of 8 cIrL can be obtained in total, and that the apparatus t of the present invention can make more than three times as much ice as in the case of only ice-making operation. However, since the time for the ice-melting operation can be made shorter than the time for the ice-making operation, a larger amount of ice can actually be made.

The apparatus shown in FIG. 1 is equipped with an overflow pipe 14 in case the deicing operation is to be shortened. In other words, when the ice-making operation constitutes a longer cycle than the ice-melting operation, the amount of return refrigerant during the ice-making operation increases, and the amount of refrigerant 111 in the high-temperature refrigerant tank 4 increases, so the overflow pipe 14 This allows the overflow w to flow to the low temperature refrigerant tank 6 side. In addition, the apparatus of the present invention is capable of producing both low-temperature refrigerant and high-temperature refrigerant by operating the refrigerator, and for this reason, in particular, the cooling water on the outlet side of the refrigerator in the cooling water circuit of the refrigerator 5 is transferred to the high-temperature refrigerant tank 4. Cooling tower 6 after passing through heat exchanger 10Vc
This allows the high-temperature refrigerant necessary for ice melting to be obtained without any other heat source, and also reduces the load on the cooling tower.

Figure @3 shows a modification of the cooler 2 used in the apparatus of the present invention, in which projections 15 are provided on the surface of the cooler 2. When using a cooler 2f with many of these protrusions,
Can generate small pieces of ice. Floating small pieces of ice is advantageous because it can increase the rate of heat dissipation in the case of cooling operation of a heat storage water tank.

FIG. 4 shows an example in which partitions 16 are provided alternately to make the refrigerant flow in the cooler 2 in a zigzag shape so that the surface temperature is uniform when a flat cooler is used. show.

Note that the cooler 2 is not limited to the illustrated example, but may be a tubular type (σ), and its arrangement may be in a rammed arrangement such as horizontal arrangement, vertical arrangement, or inclined arrangement. The material of the cooler 2 is preferably a copper plate with high thermal conductivity, and its thickness is made as thin as possible. In particular, in the case of the device of the present invention, when the thickness of ice reaches a certain level, it peels off from the surface of the cooler (melting operation), which prevents the ice-making pressure from increasing and makes it possible to reduce the thickness of the surface plate of the cooler. It can improve the heat transfer efficiency.

As described above, the apparatus of the present invention can efficiently make ice by repeating the ice making operation and the ice melting operation when chilled water and ice are made to coexist to store cold heat. Both are significantly improved, and a large amount of cooling and heating can be performed in a small-scale heat storage tank in an energy-saving manner, which is very beneficial.

[Brief explanation of the drawing]

Fig. 1 is an equipment layout system diagram showing an embodiment of the device of the present invention, Fig. 2 is a diagram showing the relationship between ice making time and ice growth thickness, Fig. 3 is a side view showing an example of a cooler, and Fig. 4 is a flat plate. FIG. 2 is a transparent perspective view showing an example of a shaped cooler. 1... Heat storage water tank 2... Cooler 6... Low temperature refrigerant tank 4... High temperature refrigerant tank 5... Refrigerator 6... Cooling tower 7. 8... Three-way valve 9.10...Heat exchanger 11...Pump 13...Timer

Claims (1)

[Claims] A cold heat storage device in which a cooler is installed in a heat storage water tank and a portion of the cold water is concentrated on the surface of the cooler, and the temperature of the refrigerant supplied to the cooler is equal to the ice making temperature. A cold heat storage device characterized by alternating the ice temperature.