JPS58145850A - Heat collection and storage capsule - Google Patents

Abstract

PURPOSE:To contrive to reduce the radiation loss from the outside surface of a closed vessel and to improve the heat collection efficiency by a structure wherein heat storage material by latent heat is packed in the closed vessel formed out of light-transmitting material and yet a tubular absorber with blackened surface is attached in the closed vessel. CONSTITUTION:The heat storage material by latent heat 2 such as polyethylene glycol is packed in the closed vessel 1 formed out of light-transmitting material such as polymethyl methacrylate-type resin and yet the tubular absorber 3 such as copper with blackened surface is attached in the closed vessel 1. Accordingly, light transmits the wall of the vessel 1 and the heat storage material 2 and then is absorbed by the absorber 3 in order to collect heat. Consequently, the temperature of the absorber 3 becomes high, resulting in melting the heat storage material 2 and at the same time producing the distribution of temperature which gradually lowers from the absorber 3 inside the vessel 1 toward the wall of the vessel 1. As a result, the radiation loss from the outside surface of the vessel 1 is reduced, resulting in improving the heat collection efficiency. Furthermore, because of the tubular absorber 3, fluid can be past inside the absorber 3, resulting in facilitating the recovery of the heat.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat collection/storage capsule, and more particularly to a solar energy heat collection/storage capsule with less heat radiation loss to the outside and high heat collection efficiency.

Conventionally, when directly collecting and storing heat from sunlight, a container with a black surface is filled with a latent heat storage material to form a heat collection and storage capsule. In such a heat collection and storage capsule, when the container is cylindrical, the black container (141 The vessel wall becomes the hottest,
The temperature distribution is such that the temperature decreases towards the inside of the container.

Therefore, even if heat is collected on the black surface, the amount of heat released outward from the black surface is large, so the heat cannot be efficiently stored in the latent heat storage material inside the container, and the heat collection efficiency is low as a heat collection and storage capsule. I had no choice but to do so.

The present invention has been made in view of the above points.

Therefore, the present invention has a method in which a latent heat storage material (2) is filled in a closed container (1) made of a material that can transmit light, and a tubular heat collector (3) with a black surface is installed inside. This is a unique heat collection and storage capsule.

The present invention will be described below with reference to embodiments shown in the drawings. Second
Figure ta+ is a schematic sectional view showing one embodiment of a heat collection and storage capsule according to the present invention. In Figure 2 (al), (1) is an airtight container, and this airtight container (1) is made of a material that can transmit light. (2) is a latent heat storage material, and (3) is a tubular material with a black surface. The heat collector, (4) is an end plate, and (5) is a screw stopper that is screwed into the latent heat storage material inlet drilled in the end plate to seal the container. )
The end plate (4) and the heat collector (3) are firmly adhered to each other.
) is also strongly bonded.

In this way, the latent heat storage material (2) is sealed so as not to leak from the closed container (1).

In addition, in the heat collection and storage capsule illustrated in FIG. Airtight container (1)
Since it is connected to the outside of the tubular heat collector (3), the fluid can pass through the inside of the tubular heat collector (3). Also, Fig. 2 1b
) as in the tubular heat collector (3), and the plate-like heat collector (
It is also possible to combine 3). The heat collection/storage capsule shown in Figure 2-) has a tubular heat collector (3) as shown in Figure 3.
The projecting portion from the end plate (4) may be closed with a closing member (6), and the latent heat storage material (2) may be further filled in the closing member (6). In addition, as shown in Figure 4, a tubular heat collector (
It can also be used in a form in which the inside of the heat collector (3) is filled with air and the openings at both ends of the heat collector (3) are closed with closing members (6). Also, connect the openings at both ends of the tubular heat collector (3) to a closed container (
2) The present invention also includes a case where there is no passage with the outside. Fifth
The figure is a sectional view showing an example of a fixing protrusion for holding and fixing.

The light-transmissive material forming the closed container (1) preferably has a high light transmittance, and materials with a light transmittance of 06 or higher give good results, and those with a light transmittance of 08 to 1 are particularly preferred. Furthermore, since the latent heat storage material is filled, it is desirable to use a material that has excellent moisture and water vapor barrier properties. In addition, since heat collection and storage due to solar radiation is repeated, it is desirable to use a material with good light resistance.Furthermore, it is desirable to have a material that is strong enough to withstand changes in pressure or stress caused by the thermal history caused by repeated heat collection and heat radiation, and the accompanying expansion and contraction of the latent heat storage material. Materials that have the following are preferred. Examples of such materials include polymethyl methacrylate resins, acrylonitrile loose≠ren copolymer resins, polycarbonate resins, and copolymer resins obtained by copolymerizing methacrylic esters and monoalkenyl aromatic monomers. is preferably used.

Glass can also be used as a material for the closed container, but for the purposes of the present invention, glass of a grade that can withstand expansion and contraction is preferred. Furthermore, the airtight container (1) is made of a multilayered material in which one or more materials having various properties are laminated in addition to the above-mentioned materials in order to improve properties such as water barrier, secondary light, light transmittance, and strength. You can leave it there.

Further, as the tubular heat collector having a black surface in the present invention, for example, a metal surface whose surface is painted black by painting or the like is preferably used. As the metal, many metals such as copper, aluminum, stainless steel, and duralumin can be used. In this way, when metal is used as the material for the heat collector (3), the heat collected on the black surface is easily transferred to the back side, which is not exposed to light, which is preferable from the viewpoint of heat collection efficiency of the heat collection and storage capsule.

The black paint used in the painting process is preferably one with excellent light resistance, such as urethane resin paint,
Not only organic paints such as acrylic resin paints and fluororesin paints, but also inorganic paints such as composite silicates and composite phosphates can be suitably used. Among these types of paints, matte paints containing inorganic pigments such as carbon black and metal oxides such as iron oxide as black pigments are particularly preferred. Furthermore, plastics such as polyethylene kneaded with black pigments such as carbon black are also suitably used as the heat collector.

Further, as the latent heat storage material in the present invention, for example, one having a melting temperature of 10 to 80°C can be suitably used, and one having a melting temperature of 20 to 60°C is easily used. In addition, a material with good light transmittance is desired.

As such a latent heat storage material, for example, polyethylene glycol, sodium thiosulfate pentahydrate, sodium hydrogen phosphate dodecahydrate, calcium chloride hexahydrate, sodium sulfate decahydrate, etc. are suitably used. Moreover, eutectic products and mixtures of magnesium nitrate and ammonium nitrate can also be suitably used.

When the heat storage capsule shown in Figure 2 (al) is irradiated with sunlight, the light first passes through the wall of the closed container and the heat storage material, and then is absorbed and collected by the heat collector (3). The heat collector (3) becomes high temperature and melts the latent heat storage material (2).In this case, since the heat collector (3) is housed inside the airtight container (1), as shown in FIG. The temperature distribution is such that the highest temperature is near the heat collector (3), and the temperature becomes lower as it approaches the wall of the closed container (1). Heat radiation loss caused by this is prevented, and heat can be collected with high heat collection efficiency.

The closed container in the present invention is not limited to the cylindrical shape shown in FIGS. 2 to 6, but also has a triangular cross section [FIG. 8 (a+
Reference] It may be rectangular and cylindrical as shown in Figure 8 (see b+), or it may be a polygonal cylindrical shape such as pentagonal, hexagonal, hexagonal, etc., or an oval cylindrical cross-section. It may also have a shape such as a rectangular parallelepiped or a truncated truncated pyramid.
The tubular heat collector may not only have a circular cross section, but may also have a tubular shape such as an ellipse, a triangle, a square, and a pentagon, hexagon, hexagon, etc.

Further, a plurality of tubular heat collectors may be housed inside the closed container. In addition, the heat collector may be a combination of a tubular shape, a plate shape, and a rod shape. In other words, if a heat collector that is a combination of a tubular shape and a plate shape as shown in Fig. 2 (bl) is used, the solar radiation surface can be maximized. Since it can be used, the heat collection efficiency is further improved.

Further, in the present invention, a heat insulating material can be provided in contact with a portion other than the portion where light is condensed.

If the sealed container is cylindrical, the back surface can be covered with a heat insulating material (9) as shown in FIGS. 6 and 9. In this case, the heat collector (
3) may be attached to the closed container with an adhesive or the like, or may be fixed by fitting both ends of the heat collector (3) between the fixing projections of the end plate.

If the sealed container (1) is in the shape of a rectangular parallelepiped, a heat insulating material (9) may be attached to the bottom side of the sealed container (1) as shown in Figure 10. It is better to do so.

Foam is preferably used as the heat insulating material. As the foam, for example, a foam made of synthetic resin such as polyethylene resin, polystyrene resin, urethane resin, etc. can be used.

The heat collection and storage capsule according to the present invention can be used in various ways. As shown in FIG. 11, a capsule installation shelf αD is provided on the inclined plate (10), and this capsule installation shelf (11
), a large number of heat storage capsules (AJ) are installed, the entire heat storage capsule is covered with a transparent cover (121), the air is trapped in the cover (121), and the wall of the airtight container (1) of the heat storage capsule is In addition, as a heat storage capsule (AJ), a tubular heat collector (3) is passed through the outside of the closed container (1) as shown in Figure 2, and the tubular heat collector A heat storage capsule (A
The heat accumulated in J can be transferred to the medium 0J and taken out.

As described above, in the heat collection and storage capsule of the present invention, a latent heat storage material is filled in a closed container made of a material that can transmit light, and a tubular heat collection body with a black surface is installed inside. Therefore, when light is irradiated, the light first passes through the wall surface of the material that can transmit light and the heat storage material that forms the closed container, and then is absorbed and collected by the heat collector, which causes heat collection. The temperature distribution can be such that the body becomes high temperature and melts the latent heat storage material, and the temperature decreases as it goes from the internal heat collector to the wall of the sealed container. In addition, since the heat collector is tubular, it is possible to create a passage between the inside of the heat collector tube and the outside of the closed container. A fluid can be passed through the inside of the heat collecting body, and heat can be recovered from the heat collection and storage capsule very easily by passing the fluid.

The present invention will be further explained below with reference to experimental examples.

Experimental Examples and Comparative Examples The performance (melting rate) of the heat collection and storage capsules shown in the "Target article column" in Table 1 was evaluated, and the results are shown in Table 1.

[Evaluation method - melting rate]

Place the capsule horizontally outdoors, collect and store 8 minutes of solar radiation while measuring the solar radiation with a pyranometer, and when the solar radiation disappears, open the capsule and check the amount of melting.
The melting rate was determined from the melting amount/total heat storage material amount. The amount of solar radiation on the day the melting rate was measured was 3000 Tki/m-Day.

According to the results in Table 1, the melting rate, that is, the heat collection and storage efficiency, is increased by 2 to 16 CX compared to the conventional black pipe with the heat collector installed.

In this heat collection and storage capsule, a latent heat storage material is filled in an airtight container made of a material that allows light to pass through, and a tubular heat collector with a black surface is installed. In addition, by passing a heat medium inside the tubular heat collecting body, the heat can be easily recovered from the heat collection and storage capsule.

[Brief explanation of the drawing]

Figure 1 shows the temperature distribution inside the heat collection and storage capsule when the heat collection and storage capsule, which is a conventional example in which a latent heat storage material is filled in a container with a black surface, collects heat from incident light in the direction of arrow a. 2(a) to 6 are schematic sectional views showing various embodiments of the heat collection and storage capsule of the present invention,
Figure 7 is an explanatory diagram showing the temperature distribution during heat collection of the heat collection and storage capsule of the present invention, Figures 8(a), (b), and 9.
10 and 10 are schematic sectional views showing other embodiments, and FIG.
The figure is a sectional view for explaining a heat storage tank using a heat collection and storage capsule according to the present invention. (1)・・・Airtight container, (2)・・・・・・
Latent heat storage material (3)...Heat collector. Applicant Asahi Dow Co., Ltd. Agent Yutaka 1) Yoshio Figure 1 Figure 6

Claims (1)

[Claims] (1) Heat collection and storage capsule 0 characterized in that a latent heat storage material is filled in a closed container made of a material that can transmit light, and a tubular heat collection body with a black surface is installed inside.