JPH06207724A - Ice heat storage apparatus - Google Patents

Abstract

PURPOSE:To improve a filling rate of ice in an ice heat storage tank by injecting a fluid in the heat storage tank, a temperature of which fluid is lower than a solidifica tion point of a heat storage medium and which has a greater specific gravity than the heat storage medium and is not dissolvable in the heat storage medium, into the heat storage medium in the ice heat storage tank, and releasing an overcooled state of the fluid. CONSTITUTION:An ice heat storage tank 1 is filled with water M being a heat storage medium and with a refrigerant R being a nonaqueous fluid, a temperature of which is less than a solidification point of the heat storage medium, i.e., less than 0 deg.C and which has a greater specific gravity than the water M. To the lower end of a refrigerant storage part 3 there is connected one end of a refrigerant piping 5 for recovering the refrigerant R in the refrigerant storage part 3. The other end of the refrigerant piping 5 is connected with a lower side wall of the ice heat storage tank 1 and a nozzle 11 for injecting the refrigerant R into the ice heat storage tank 1 is attached to the tip end of the piping 5. At a location opposite to the nozzle 11 there is mounted on an ultrasonic vibrator 13 serving to release an overcooled state of the refrigerant injected from the nozzle 11. Thereby, heat exchange of the fluid with the heat storage medium is promoted and hence a portion where a distance required for the heat exchange is shortened can be extended as an ice storage region.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice heat storage system for freezing and ice-making a heat storage medium by direct contact between the heat storage medium and a liquid which is below the freezing point of the heat storage medium and does not dissolve in the heat storage medium, and utilizes the heat absorbing action of this ice-making product. Regarding the device.

[0002]

2. Description of the Related Art An air conditioning system equipped with an ice heat storage device is capable of leveling electric power by shifting a part of the electric power demand for cooling concentrated during the daytime in summer to nighttime. In other words, low-cost nighttime electricity is used to store cold heat, and by using this cold heat for air conditioning in the daytime, users can obtain air conditioning with low running costs, while electric power companies can install equipment by peak shifting power demand. The operating rate is improved.

The methods of making ice in the ice heat storage device are roughly classified into a static type in which ice accretion / thawing is performed on the ice making heat exchanger and a dynamic type in which ice is not made to accrete on the ice making heat exchanger.

Generally, the static type has a simple structure, but on the other hand, the heat transfer resistance increases as the ice grows.
While the cooling temperature for ice making has to be gradually lowered, which has the essential drawback of lowering efficiency,
Since the dynamic type can raise the cooling temperature of the refrigerant higher than the static type, the coefficient of performance of the refrigerator is good and there is no need to arrange a heat exchanger in the ice heat storage tank and the filling rate of ice (IPF: Ice Packing Factor)
Also improves.

There are various types in the dynamic type,
At the same time, it is a non-water-soluble liquid (refrigerant) that has a specific gravity of 1 or more at low temperature.
There is a method to make ice by direct contact with water. this is,
The water-insoluble liquid existing at the bottom of the heat storage tank is cooled to 0 ° C. or less and jetted into water through a nozzle arranged in the heat storage tank. Due to the circulation of the cooled water-soluble liquid, sherbet-like ice (ice particles) is generated in the heat storage tank, and this ice rises due to buoyancy and is stored from the upper portion of the heat storage tank and floats. Then, if necessary, the endothermic action when the ice is melted is used for the cooling operation of the air conditioner.

[0006]

However, in the dynamic ice heat storage system as described above, the sherbet-like ice that is generated and floats has almost no compression between the ices, so that the volume ratio of the ice is low. , The IPF was low. The heat exchange between the water-insoluble liquid and the water is performed while the water-insoluble liquid ejected from the nozzle into the water falls in the water.Therefore, the nozzle must be arranged for heat exchange from the bottom of the ice storage tank. Must be a certain distance above. Usually, this fall distance is required to be about 1 m. That is, the area below the nozzle up to about 1 m is the ice making area, and the area above the nozzle is the ice storage area. In this case, the area lower than the nozzle in the ice heat storage tank becomes a dead space, and it is not possible to store ice,
It is a cause of low IPF. If it is attempted to make ice together with ice storage in a region below the nozzle, the nozzle freezes during ice making, and the ejection holes are clogged, making it impossible to supply the refrigerant.

Therefore, an object of the present invention is to further improve the filling rate of ice in the ice heat storage tank.

[0008]

In order to achieve the above object, the present invention provides a heat storage medium and a liquid having a liquid temperature below the freezing point of the heat storage medium and having a specific gravity larger than that of the heat storage medium and not dissolved in the ice. Stored in a heat storage tank, the bottom of this ice storage tank is connected to one end of a liquid recovery pipe that recovers the liquid and has a cooling means in the middle, and the other end of the liquid recovery pipe is filled with the liquid in the ice storage tank. A jetting means for jetting is provided, and a supercooling releasing means for releasing the supercooled state of the liquid jetted from the jetting means is provided in the ice heat storage tank.

The supercooling releasing means may be integrated with the jetting means.

[0010]

According to the ice heat storage device having such a configuration, the liquid staying at the bottom of the ice heat storage tank is recovered from the liquid recovery pipe and cooled by the cooling means, and then ejected from the ejection means into the ice heat storage tank. The heat is exchanged by directly contacting the heat storage medium. When the supercooling releasing means is operated in this state, the supercooled state of the liquid ejected from the ejecting means is released, heat exchange is promoted, and ice making is rapidly performed.

Further, when the supercooling releasing means integrated with the jetting means is operated, it becomes difficult for the jetting holes of the jetting means to be iced, and when the ice is iced, it is peeled off.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the overall structure of a dynamic ice heat storage device according to the first embodiment of the present invention. The ice heat storage tank 1 is filled with water M, which is a heat storage medium, and a refrigerant R, which is a non-water-soluble liquid having a specific gravity not higher than the freezing point of the heat storage medium, that is, a liquid temperature of 0 ° C. or less and a specific gravity higher than that of the water M. . A refrigerant reservoir 3 protruding downward is provided at the bottom of the ice heat storage tank 1, and the refrigerant R, which has a larger specific gravity than the water M, is separated from the water M and mostly exists in the refrigerant reservoir 3. It will be.

One end of a refrigerant pipe 5 as a liquid recovery pipe for recovering the refrigerant R in the refrigerant reservoir 3 is connected to the lower end of the refrigerant reservoir 3. The refrigerant pipe 5 has a refrigerant reservoir 3
A refrigerant pump 7 that circulates the refrigerant R and a refrigerator 9 that serves as a cooling unit that cools the refrigerant sent from the refrigerant pump 7 are sequentially provided from the side. The other end of the refrigerant pipe 5 is connected to the lower side wall of the ice heat storage tank 1, and a nozzle 11 as a jetting means for jetting the refrigerant R into the ice heat storage tank 1 is attached to the tip thereof.

The nozzle 11 on the inner wall of the lower side of the ice heat storage tank 1
An ultrasonic transducer 13 as a supercooling canceling unit that cancels the supercooled state of the refrigerant R ejected from the nozzle 11 and promotes heat exchange with the water M is mounted at a position opposed to. A plurality of ultrasonic transducers 13 are arranged so that the ultrasonic waves are radiated toward the region where the refrigerant R and the water M come into contact with each other to produce ice, and each ultrasonic transducer 13 generates a high voltage at a high frequency. Connected to the oscillator circuit 15 and driven by the oscillator circuit 15.

In the ice heat storage device having such a structure, when the pump 7 is driven, the refrigerant R in the refrigerant storage portion 3 is cooled to an arbitrary temperature by the refrigerator 9 and the water in the ice heat storage tank 1 is supplied from the nozzle 11 to the water. It is ejected as fine particles into M. The refrigerant R jetted into the water M directly contacts the water M to perform heat exchange, falls to the bottom of the ice heat storage tank 1 while cooling the water M, and is guided to the refrigerant reservoir 3. Then, this process is repeated, and when the temperature of the water M reaches 0 ° C., the refrigerant R and the water M come into contact with each other to start producing ice.

Here, the ultrasonic transducer 13 arranged in the ice heat storage tank 1 is driven to irradiate the heat exchange region between the water M and the refrigerant R with ultrasonic waves. The ice making at this time is due to the particles of the refrigerant R supercooled, and the generated ice becomes ice particles (sherbet-like ice) K, but the supercooled state of the refrigerant R is rapidly changed by the irradiation of ultrasonic waves. As it is released, the production of ice is accelerated. The generated ice particles K rise in the water M due to buoyancy and float above the ice heat storage tank 1, and if this state is continued, they are gradually stored from the upper part to the lower part of the ice heat storage tank 1. Become.

Since the generation of ice is accelerated by the irradiation of ultrasonic waves, the distance required for heat exchange until the refrigerant R is ejected from the nozzle 11 and reaches the bottom of the heat storage tank 1 is shortened. Therefore, the nozzle 11 can be arranged at a lower position in the ice heat storage tank 1, the ice storage area in the ice heat storage tank 1 can be expanded downward, and the ice filling rate is improved.

FIG. 2 shows a second embodiment of the present invention. In this embodiment, the nozzle 17 mounted on the side wall of the ice heat storage tank 1 is used.
In addition, the ultrasonic transducer 19 as the supercooling releasing means is integrated. The nozzle 17 has a so-called ultrasonic horn shape in which the portion to which the ultrasonic transducer 19 is attached is exposed outside the ice heat storage tank 1 as an enlarged portion 17a. An electrode 21 is provided on the ultrasonic transducer 19, and a heater 23 is mounted around the ejection hole 17b at the tip of the nozzle 17.

Also in this embodiment, the ultrasonic transducer 19
When is driven, ultrasonic waves are radiated from the tip of the nozzle 11 into the water M, the supercooled state of the refrigerant R is released, and the generation of ice is promoted. Therefore, the same effect as in the first embodiment can be obtained. .

Regarding ice accretion on the tip of the nozzle 17, not only when the ice particles K exist near the nozzle 17, but also when there is no ice particle K near the nozzle 17 and only water M is present. Even if there is, it may occur.

However, in this embodiment, the ultrasonic transducer 1
By driving 9, the area around the ejection hole 17b at the tip of the nozzle 11 is less likely to be iced, and even if iced, ice is detected by some means and the ultrasonic transducer 19 is driven. Alternatively, when the ultrasonic transducer 19 is driven at regular intervals, ultrasonic energy is concentrated on the tip of the nozzle 17 and the ice that has accumulated on the tip of the nozzle 17 can be separated. As a result, the freezing and clogging of the ejection holes 17b are prevented, and as a result, the refrigerant R can be continuously supplied, which makes it possible to make ice for a long time. When the heater 23 is energized together with the driving of the ultrasonic transducer 19, the effect of peeling off the iced ice is further improved.

Further, when the refrigerant R is ejected from the nozzle 17, it is possible to change the diameter of the fine particles of the refrigerant R ejected from the ejection holes 17b by changing the input level of the ultrasonic transducer 19. Therefore, it can be expected that ice will be generated in the optimum ice-making state.

The present invention is not limited to the ice making method in which the ice particles K are produced by the direct contact between the refrigerant R and the water M, and, for example, as shown in FIG. The refrigerant R is jetted into the heat transfer pipe 25 from the nozzle 11 below the heat pipe 25, and the ice particles K are generated by the refrigerant R flowing out from the upper end of the heat transfer pipe 25.
It is naturally applicable to the ice making method for producing the ice blocks L on the outer wall of the.

[0025]

As described above, according to the present invention, a liquid whose liquid temperature is lower than the freezing point of the heat storage medium and has a specific gravity higher than that of the heat storage medium and which is not dissolved in the heat storage medium is stored in the heat storage medium in the ice storage tank. Since the supercooled state of the liquid is ejected by the supercooling releasing means, heat exchange between the liquid and the heat storage medium is promoted, and the portion where the distance required for heat exchange is shortened is set as the ice storage area. It can be expanded and the filling rate of ice can be improved.

Further, the supercooling releasing means is integrated with the jetting means, so that icing on the jetting means can be prevented.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the overall configuration of an ice heat storage device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a main part showing a second embodiment of the present invention.

FIG. 3 is a sectional view showing the overall structure of an ice heat storage device according to a third embodiment of the present invention.

[Explanation of symbols]

 M Water (heat storage medium) R Refrigerant (liquid) 1 Ice heat storage tank 5 Refrigerant pipe (liquid recovery pipe) 9 Refrigerator (cooling means) 11 Nozzle (spouting means) 13,19 Ultrasonic transducer (supercooling releasing means)

Claims (3)

[Claims] 1. A heat storage medium and a liquid whose liquid temperature is below the freezing point of the heat storage medium and whose specific gravity is greater than that of the heat storage medium and does not dissolve in the heat storage medium are stored in an ice heat storage tank, and at the bottom of this ice heat storage tank,
The liquid recovery pipe is connected to one end of a liquid recovery pipe provided with a cooling means on the way, and the other end of the liquid recovery pipe is provided with a jetting device for jetting the liquid into the ice heat storage tank, and jetted from the jetting device. An ice heat storage device, characterized in that supercooling release means for releasing a supercooled state of a liquid is provided in the ice heat storage tank. 2. The ice heat storage device according to claim 1, wherein the supercooling releasing means is integrated with the ejection means. 3. The ice heat storage device according to claim 1, wherein the supercooling releasing means is an ultrasonic vibrator.