JPH0816571B2 - Heat storage state detection device for ice heat storage equipment - Google Patents

Description

The present invention relates to an ice heat storage facility for storing a refrigerant in a solid-liquid mixed phase sherbet state in an ice heat storage tank as a cold heat source for cooling, etc. The present invention relates to a device for detecting the heat storage state of an ice heat storage tank.

[Conventional technology]

In the type of ice heat storage in which ice is grown and accumulated around the cooling coil in the heat storage tank, the heat storage state (heat storage amount, etc.) can be determined by detecting the thickness of the growing ice. Since it is not possible in the type of ice heat storage that is stored in the mixed phase sherbet state,
Conventionally, similar to cold water heat storage, the heat storage state is determined based on the temperature detection of the stored refrigerant, or the presence of ice particles in the stored refrigerant is detected based on the liquid level detection of the heat storage tank using the volume expansion accompanying the cooling and solidification of the refrigerant. The heat storage state was judged by obtaining the ratio (the literature cannot be shown).

[Problems to be solved by the invention]

However, since the so-called ice heat storage originally stores heat using solidified latent heat, it is not possible to accurately determine the heat storage state by sensible heat determination based on temperature detection. In addition, since the liquid level detection itself has many disturbance elements such as a wave level on the liquid surface and a large detection error, there is also a problem that it is difficult to stably and accurately determine the heat storage state.

An object of the present invention is to make it possible to stably and accurately determine the heat storage state of an ice heat storage tank by rational means adapted to a state where the refrigerant is in a solid-liquid mixed phase sherbet state.

[Means for solving problems]

The characteristic configuration of the heat storage state detection device in the ice heat storage equipment according to the present invention detects the ultrasonic transmittance of the stored refrigerant as information for determining the heat storage state in the ice heat storage tank that stores the refrigerant in a solid-liquid mixed phase sherbet state. There is a plurality of ultrasonic transmittance detecting means provided in the vertical direction of the ice heat storage tank, and the operation and effect thereof are as follows.

[Work]

In other words, when the abundance of ice particles in the stored refrigerant changes, the ultrasonic transmittance of the refrigerant changes accordingly, so by observing the ultrasonic transmittance of the stored refrigerant, the ice existing state in the refrigerant can be grasped. Thus, the heat storage state in the ice heat storage tank can be determined.

Further, in the ice heat storage tank for storing the solid-liquid mixed phase refrigerant in the sherbet state, ice is usually stored from the upper part. Therefore, by comparing the detection results of the ultrasonic transmittance detection means adjacent to each other in the vertical direction in the heat storage tank, it is possible to specify the boundary position between the layer containing ice and the layer containing only water,
It is possible to more accurately determine the ice storage state.

〔The invention's effect〕

That is, first, since the heat storage state is determined based on the correlation with the existence rate of ice particles, the heat storage state can be determined totally including the latent heat.

Further, since the boundary height between the existence layer of ice and the existence layer of only water can be recognized, it is possible to judge the approximate amount of ice with respect to the total capacity of the heat storage tank. Therefore, together with the determination result based on the abundance ratio of the ice particles, it becomes possible to stably and accurately determine the heat storage state of the ice heat storage tank by being well adapted to the ice heat storage in the solid-liquid mixed phase sherbet state, and eventually , It has become an extremely useful and practical heat storage state detection device in operation control of a cooling system using this type of ice heat storage.

〔Example〕

 Next, embodiments of the present invention will be described with reference to the drawings.

The basic heat pump used in the present invention comprises a compressor, a condenser, an expansion valve, and a heat pump circuit consisting of an ice maker as an evaporator, and circulates a primary refrigerant in this order, and an ice maker and an ice heat storage tank. (6) is connected to the circulation path of the secondary refrigerant so that the circulation secondary refrigerant is put into a solid-liquid mixed phase sherbet state in the ice making machine by the operation of the heat pump circuit, and the sherbet-shaped secondary refrigerant is stored with ice heat. The heat is stored in the tank (6) to store cold heat for the purpose of cooling or the like.

In the ice heat storage tank (6) of the present invention, as shown in FIG.
A plurality of ultrasonic transmissivity detecting means consisting of an ultrasonic transmitter (8) and a receiver (9) are vertically arranged side by side with respect to the main body of the ice heat storage tank (6), thereby providing a heat pump circuit. The heat storage state of the ice heat storage tank (6) is determined stepwise for the purpose of, for example, capacity control.

As for one set of the ultrasonic transmittance detecting means, the stored refrigerant inside the ice heat storage tank (6) is directly irradiated with ultrasonic waves by the ultrasonic transmitter (8) and the receiver ( 9), the ultrasonic transmittance is obtained, and the heat storage state in the ice heat storage tank (6) is determined based on the detection result.

That is, since ice and water have different ultrasonic wave transmittances, the ice heat storage amount is determined by utilizing the fact that the modulated sound wave transmittance also changes according to changes in the ice presence rate.

Originally, if a set of ultrasonic transmittance detecting means is provided at a predetermined height position of the ice heat storage tank (6), the sherbet-like ice layer will be stored from the upper part. The ice heat storage state can be grasped by detecting that the ice has increased to the position of the sound wave transmittance detecting means.

However, ultrasonic waves are reflected on the ice surface, or ultrasonic transmittance is affected by minute bubbles in water, so there is a limit to detection accuracy with only a single ultrasonic transmittance detection means. .

Therefore, in this embodiment, ultrasonic transmittance detecting means are provided at a plurality of positions in the vertical direction of the ice heat storage tank (6),
Improves the accuracy of ice heat storage detection.

That is, since the detection result in the ice existing layer above the ice heat storage tank (6) and the detection result in the ice existing layer below the ice heat storage tank (6) are clearly different, both detection results are obtained. By comparing the above, it is possible to roughly recognize the boundary height between the existence layer of ice and the existence layer of only water.

Therefore, the amount of ice with respect to the total capacity of the heat storage tank can be accurately determined together with the determination result based on the presence rate of the ice particles.

Then, according to this determination result, the operation of the compressor or the like is controlled via an automatic operation control device provided separately.

[Another embodiment]

 Next, another embodiment of the present invention will be described.

In the said Example, the structure which irradiates an ultrasonic wave over the whole ice heat storage tank (6) was shown. However, as shown in FIG. 2, a circulation path (13) is provided at a predetermined position in the vertical direction of the ice heat storage tank (6), and the refrigerant is branched and circulated in the circulation path (13) so that the circulation of the circulation refrigerant is increased. The heat storage state of the ice heat storage tank (6) may be determined by detecting the sound wave transmittance.

With such a configuration, the ice heat storage amount can be detected even by the ultrasonic transmittance detecting means having a small output.

In the ultrasonic transmittance detection means, various improvements can be made in the specific transmittance detection mode and its structure.

The control performed based on the detected ultrasonic transmittance is not limited to the start and stop of the compressor.For example, the control on the consumption side of the stored cold heat is performed based on the detected ultrasonic transmittance. The detected ultrasonic wave transmissivity can be applied as information for various controls related to the heat storage state in (6), or the detected ultrasonic wave transmissivity may be used simply for displaying the heat storage state. .

The refrigerant is not limited to water and various aqueous solutions,
Other various liquid agents may be used.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention. FIG. 2 is a structural diagram showing another embodiment of the present invention. (6) ... Ice heat storage tank, (8), (9) ... Ultrasonic transmittance detecting means.

Claims (1)

[Claims] 1. An ice heat storage facility for storing a refrigerant in a solid-liquid mixed phase sherbet state in an ice heat storage tank (6), wherein the information of the stored refrigerant is used as information for determining the heat storage state in the ice heat storage tank (6). A heat storage state detecting device for an ice heat storage facility, wherein a plurality of ultrasonic wave transmittance detecting means (8), (9) for detecting a sound wave transmittance are provided side by side in the vertical direction of the ice heat storage tank (6).