JPS58156151A - Heat accumulating tank - Google Patents

Abstract

PURPOSE:To lessen the stress in a piping and to increase the amount of radiation thereby increasing the utilization efficiency as a whole, by providing a liquid heat accumulating layer in the heat accumulating tank so that the parts of heat exchange pipes in the heat accumulating tank may not be in direct contact with a heat accumulating material. CONSTITUTION:A liquid heat accumulating tank 12 is formed wherein a liquid heat accumulating material 11 (e.g. water) as a thermal and mechanical buffering part is confined so that the part of the heat exchange pipe 3 for heat accumulation and the part of the heat exchange pipe 4 for heat radiation in the heat accumulating tank 2 may not be in direct contact with the latent heat accumulating material 7 (e.g. hydrated inorganic salts). That is, the heat accumulation to the liquid heat accumulating material 11 or the heat radiation from the heat accumulating material 11 are carried out through the pipes 3, 4. An outer heat accumulating tank 2 containing a latent heat accumulating material 1 is formed outside of the tank 12 so that the heat accumulating tank is formed to have a double wall structure as a whole. As a result, the stress to the piping due to the change in the volume of the heat accumulating material is lessened, and the difference in conditions for heat transfer when heat accumulation or heat radiation is effected is minimized, so that the amount of heat radiation is increased thereby the utilization efficiency as a whole can be increased.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention, @, relates to a thermal storage tank for cooling and heating that utilizes solar heat, and
The present invention relates to a latent heat storage tank whose phase has changed to l#.

C41,, IKsW 2 y Hibiki 11dl Heat lumps include, for example, as shown in Figure 1, heat storage 2 with heat storage material 1 sK heat storage heat exchange pipe 3 and heat radiation heat exchange pipe 4
Most of them are equipped with .

When actually designing an eccentric heating and cooling system using solar heat, the required heat storage capacity is large, and a To6 heat storage tank requires a large space. In order to store a large amount of heat per rounded unit volume, it is common to use latent heat storage materials that utilize phase change.

There are two major problems when using latent SM heat storage materials:

One is that the change in solid phase and liquid phase is accompanied by a change in volume. For example, approximately SS for inorganic hydrated salts.

For paraffinic mixtures there is a change of about 10-.

Furthermore, in general, solidification and melting of the heat storage material do not proceed uniformly, and a liquid phase portion and a solid phase portion coexist.

Therefore, stress may be generated due to the expansion and contraction of the heat storage material during phase change, and there is a large risk of damage to the heat exchange pipe. In particular, heat exchange pipes are coiled pipes in order to increase the contact area with the heat storage material9, and even if they are straight pipes, they have many branch pipes and have a complex structure, so they are susceptible to stress from the heat storage material. is particularly weak.

Secondly, the phase change of the heat storage material occurs from the contact surface with the heat exchange pipe, so during heat dissipation, the area around the heat exchange pipe first becomes Kalt.
This prevents heat transfer within the heat storage material after it hardens.

In other words, when a low-temperature fluid is flowed through the heat exchange pipe 4 for heat dissipation, the area around the heat exchange pipe is covered with a solid phase, and the thermal conductivity of this precipitated and growing solid phase is low, so the thermal resistance of the entire system is large. Become. For this reason, the specific heat energy stored in the material is difficult to utilize effectively, making it difficult for the latent heat storage material to exhibit its high heat storage density.

[Purpose of the invention]

The purpose of the present invention is to alleviate the stress on piping caused by changes in the volume of heat storage material, reduce the difference in heat transfer conditions during heat storage and heat radiation, increase the amount of heat radiation, and improve overall utilization efficiency. It is about providing.

[Summary of the invention]

The feature of the present invention is that, for the above-mentioned purpose, as shown in FIG. 9. A space 12 for enclosing a liquid heat storage material "11" is formed as a mechanical buffer part.

[Embodiments of the invention]

The embodiment of the present invention is shown in detail in FIG. 2 regarding #i.

A liquid heat storage tank 12 containing a liquid heat storage material 11 that utilizes 11iIII heat is formed. There is a heat exchange pipe 3ν for heat storage in the tank.
and a heat exchange pipe 4 for heat dissipation pass through, and heat is stored in the liquid heat storage material 11 or heat is radiated from the liquid heat storage material 11, respectively. Furthermore, an external heat storage tank 2 containing latent heat storage 1lt1 is formed outside the liquid storage tank 12, and the overall structure is a double-structured heat storage tank.

As mentioned above, the cross-sectional shape of the liquid heat storage tank 12 of the nenai-en can be freely selected, for example, circular as shown in Fig. 3, rectangular as shown in Fig. 4, or other shapes according to the usage conditions and purpose. . Depending on the design conditions of the heat exchange pipe, it is possible to divide the liquid heat storage tank 12 into two parts, the heat storage side and the radiation side. Choice is possible. The liquid heat storage tank 12 is made of a material that does not increase the thermal resistance between the latent heat storage material 1 and the liquid heat storage material 11.

It goes without saying that it must have a good structure and be chemically stable with the heat storage material.

〔Effect of the invention〕

According to the present invention, the volume change accompanying the melting and solidification of the heat storage material 1 does not directly apply stress to the heat exchange pipes 3 and 4, and the risk of breakage is extremely small. Furthermore, water is essentially used as the liquid heat storage material 11.

Glycols, oils, etc. are limited9, and the selection of corrosion-resistant materials has a high degree of freedom. The liquid coming out of the heat storage material 11 that comes into contact with the heat exchange pipe is heat storage.

Thermal conditions remain constant regardless of heat radiation, resulting in a highly reliable heat storage tank. Similarly, the thermal uniformity inside the liquid heat storage-12 allows the heat transfer between the heat bud and the heat material l to proceed smoothly. Furthermore, the quasi-body thermal material 11 is connected to the heat exchange pipes 3, 4 and IW.
By interposing the liquid heat storage material 11 between the liquid heat storage material 11 and the latent heat storage material 11, mild conditions are set according to the specific heat and thermal conductivity of the liquid heat storage material 11 to avoid rapid heat exchange between the heat source or load side and the latent heat storage material 1. be able to. This can prevent the precipitation and growth of the solid phase due to rapid heat exchange bending, especially during heat dissipation, and contributes to improving the utilization rate of the latent heat storage material 1. Thermal 9 A liquid heat storage material with a mechanical slowing effect is interposed between the heat exchange pipe and the latent heat storage material, which can reduce the effects of stress and corrosion on the pipes, and also reduce the effects of stress and corrosion on the heat exchange surface. It has the effect of being able to prevent the formation of a barrier against heat conduction.It is also possible to fill in an inert gas and attach fins to assist heat conduction, etc., so that it can be used regularly inside the SaraKm heat storage tank 2. As shown in FIG. 5, a plurality of liquid heat storages 412 may be installed in the latent heat storage tank 2.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a conventional heat storage tank, FIG. 2 is a cross-sectional view of the heat storage tank of the present invention, and FIGS. 3, 4, and 5 are cross-sectional views of other examples of the $invention heat storage tank. be. l..Latent heat storage material 2..Latent heat storage tank 11..Liquid heat storage material 12..Body heat storage 3..Heat exchange pipe for heat storage 4.Heat exchange vibrator for heat radiation (7317) Representative Patent Attorney Chika Nori Yu Maro (and 1 other person) Figure I Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] A heat storage tank characterized in that a part of a heat exchange pipe related to the inside of the heat storage tank is not brought into direct contact with the heat storage material, but a layer of heat storage material is interposed therebetween.