CN204923503U - Take through type single tube solar of semiellipse glass lid - Google Patents

Abstract

The utility model discloses a straight-through single-tube solar absorber with a semi-elliptical glass cover, which comprises an absorbing tube and a glass cover below the absorbing tube. The absorbing tube is a straight-through metal round tube. The absorbing tube The upper half of the circumference is covered with a layer of annular insulation layer with a broken gap in the lower part. The insulation layer coincides with the center of the absorption pipe, and the lower half circumference of the absorption pipe is exposed to the insulation layer. The glass cover is a hollow half An ellipse cover, the glass cover buckles the insulation layer from the side of the absorption tube exposed to the insulation layer. The absorber uses the refraction of the semi-elliptical glass cover to increase the concentration of reflected light, and at the same time reduce the amount of light projected on the insulation layer, greatly improving the efficiency of solar heat utilization.

Description

Straight-through monotube solar absorber with semi-elliptical glass cover

technical field

The utility model relates to solar light and heat absorbing equipment, in particular to a straight-through single-tube solar absorber with a semi-elliptical glass cover.

Background technique

With the increasingly serious problems of energy consumption, population increase, and environmental damage, solar energy is an inexhaustible clean energy, and solar thermal utilization has gradually become a hot research topic. Concentrating heat collectors have a higher operating temperature and higher conversion efficiency. With the advancement of technology, the cost needs to be further reduced, and it has great potential.

The absorber is a very important part of the concentrating heat collector. Most of the glass covers of the existing cavity-type absorbers are flat plates, and the light can only be projected on the designed absorption surface after passing through the flat glass cover. When refracting twice, the light shifts outward for a certain distance, reducing the light received on the absorbing surface. In addition, a large part of the light is lost due to being projected on the insulation cotton, which reduces the optical efficiency.

Utility model content

The purpose of this utility model is to provide a straight-through single-tube solar absorber with a semi-elliptical glass cover. The absorber uses the refraction of the semi-elliptical glass cover to increase the concentration of reflected light, and at the same time reduce the amount of light projected on the insulation layer. The amount of light greatly improves the efficiency of solar heat utilization.

The above purpose of the utility model is achieved through the following technical solutions: a straight-through single-tube solar absorber with a semi-elliptical glass cover, including an absorbing tube and a glass cover located below the absorbing tube, characterized in that: the absorbing tube It is a straight-through metal round tube. The upper half circumference of the absorption tube is covered with a circular insulating layer with a cutout in the lower part. The thermal insulation layer coincides with the center of the absorption tube. The lower half circumference of the absorption tube The glass cover is a hollow semi-elliptical cover, and the glass cover is buckled on the side of the insulation layer exposed from the absorption tube to the insulation layer.

In the present utility model, the material of the absorption pipe is steel or stainless steel.

In the utility model, the material of the thermal insulation layer is slag wool or glass wool or microporous calcium silicate.

In the utility model, the exposed lower half circumference of the absorbing tube is coated with an absorbing coating, which can absorb as much heat flow as possible in the short-wave band of solar radiation, and suppress the long-wave band heat radiation emitted by itself to the environment, thereby reducing heat loss .

In the utility model, the ratio of the long axis to the short axis of the glass cover is 6:5, the ratio of the long axis of the glass cover to the inner diameter of the absorption tube is 3:1, and the long axis of the glass cover to the outer diameter of the insulation layer The diameter ratio is 1.1:1.

In the utility model, the gap of the thermal insulation layer is a fan-shaped gap, and the thermal insulation layer has an inner arc surface and an outer arc surface, and the central angle corresponding to the outer arc surface is 227.4°.

In the utility model, the glass cover adopts ultra-clear glass with a light transmittance above 91.5%.

In the present utility model, the outer diameter of the absorption pipe is 204 mm, and the inner diameter of the pipe is 200 mm.

Compared with the prior art, the absorber of the present invention adopts a semi-elliptical glass cover, on the one hand, it can reduce the flow of air inside and outside the cavity, restrain the convective heat exchange between the absorber and the outside air, and make the heat flow evenly distributed; , the semi-elliptical cross-section used can play the role of gathering reflected light, so that most of the light is gathered on the lower half circumference of the absorbing tube, effectively reducing the solar heat loss caused by the light falling on the insulation layer.

Description of drawings

The utility model will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Fig. 1 is the working state schematic diagram of the utility model absorber;

Fig. 2 is a schematic diagram of the overall structure of the absorber of the present invention.

Explanation of reference signs

1. Absorbing tube; 2. Absorbing coating; 3. Glass cover; 4. Refracting light; 5. Reflector;

6. Incident light; 7. Reflected light; 8. Insulation layer;

Detailed ways

The straight-through single-tube solar absorber with a semi-elliptical glass cover as shown in Figure 1 and Figure 2 includes an absorber tube 1 and a glass cover 3 below the absorber tube 1, and the absorber tube 1 is a straight-through metal round tube , the specific material is steel, and stainless steel can also be used. The outer diameter of the absorption pipe 1 is 204mm, and the inner diameter of the pipe is 200mm. That is, the upper half circumference of the absorption pipe 1 is wrapped by an insulating layer, and the lower half circumference of the absorption pipe 1 is not wrapped by an insulating layer. The insulation layer 8 coincides with the center of the absorption pipe 1. The thickness of the insulation layer 8 is 163mm. The insulation layer 8 has an inner arc surface and an outer arc surface. The inner arc surface is close to the upper half circumference of the absorption tube 1. The central angle corresponding to the face is 227.4°.

The insulation layer 8 is made of slag wool, and glass wool or microporous calcium silicate can also be used. The broken fan-shaped annular gap provided at the bottom of the insulation layer 8 makes the lower half circumference of the absorption pipe 1 exposed to the insulation layer 8, reducing the projection The quantity of light on the insulation layer 8 is also to make the lower half circumference of the absorbing tube 1 directly exposed to the sunlight, and the absorbing tube 1 is coated with a selective absorbing coating 2 on the exposed lower half circumference to enhance the protection against the sun. light absorption efficiency.

The glass cover 3 is a hollow semi-elliptical cover. The glass cover 3 is made of ultra-clear glass with a light transmittance of more than 91.5% and a refractive index of 1.544. The major axis of the glass cover 3 is 600 mm, and the minor axis is 500 mm. The ratio of the long axis of the glass cover 3 to the inner diameter of the absorption tube 1 is 3:1, the outer diameter of the insulation layer 8 is 273mm, and the ratio between the long axis of the glass cover 3 and the outer diameter of the The ratio is 2.2:1, the glass cover 3 is exposed from the absorption tube 1 to the side of the insulation layer 8, and the insulation layer 8 is buckled. The space surrounded by the layer 8 constitutes the absorption chamber of the absorber, and the sunlight enters the absorption chamber after being refracted by the semi-elliptical glass cover, and then enters the lower half circumference of the absorption tube 1 .

The glass cover 3 can reduce the flow of air inside and outside the cavity, inhibit the convective heat transfer between the absorber and the outside air, and make the heat flow evenly distributed. At the same time, the glass cover 3 adopts a semi-elliptical shape, which can increase the concentration of reflected light through refraction, thereby reducing projection The light on the thermal insulation cotton plays a role in improving the optical efficiency.

When the absorber of this embodiment is used in a linear Fresnel reflector concentrator, the absorber 1 is a longitudinally extending pipe, and the heat transfer medium flows in from one end of the absorber 1 and flows out from the other end, and the longitudinally extending linear Fresnel The Neel reflector concentrator gathers the heat flow of solar radiation to the exposed lower half circumference of the absorber 1, the working fluid flows in the absorber 1, the incident light 6 is reflected by the reflector 5 to the surface of the glass cover 3, and enters the glass cover 3 The refracted light 4 is formed, and the refracted light 4 is emitted from the other side of the glass cover 3 and refracted again, and gathers on the lower half circumference of the absorption tube 1. After the working fluid absorbs heat, it acts as a heat carrier to bring heat to the heat exchange device. The incident light 6 is reflected by the mirror 5 and refracted and absorbed by the elliptical glass cover. Most of the light can reach the tube surface of the lower half circumference of the absorber 1 coated with the selective absorbing coating 2 to be absorbed.

The above-mentioned embodiments of the utility model are not limiting the protection scope of the utility model, and the implementation manner of the utility model is not limited thereto. On the premise of not departing from the above-mentioned basic technical idea of the present utility model, other modifications, replacements or changes made to the above-mentioned structure of the present utility model in various forms shall fall within the protection scope of the present utility model.

Claims (8)

1. A straight-through single-tube solar absorber with a semi-elliptical glass cover, comprising an absorbing tube and a glass cover positioned below the absorbing tube, characterized in that: the absorbing tube is a straight-through metal circular tube, and the absorbing tube The upper half circumference of the tube is covered with a layer of circular insulating layer with a broken gap in the lower part, the insulating layer coincides with the center of the absorbing tube, the lower half of the absorbing tube is exposed to the insulating layer, and the glass cover is hollow A semi-elliptical cover, the glass cover buckles the insulation layer from the side of the absorption tube exposed to the insulation layer. 2. The straight-through single-tube solar absorber with a semi-elliptical glass cover according to claim 1, characterized in that: the absorber is made of steel or stainless steel. 3. The straight-through single-tube solar absorber with a semi-elliptical glass cover according to claim 1, characterized in that: the material of the thermal insulation layer is slag wool or glass wool or microporous calcium silicate. 4. The straight-through single-tube solar absorber with a semi-elliptical glass cover according to claim 1, characterized in that: the exposed lower half circumference of the absorber tube is coated with an absorbing coating. 5. The straight-through single-tube solar absorber with a semi-elliptical glass cover according to claim 1, characterized in that: the ratio of the major axis to the minor axis of the glass cover is 6:5, the major axis of the glass cover and The ratio of the inner diameter of the absorption tube is 3:1, and the ratio of the long axis of the glass cover to the outer diameter of the insulation layer is 1.1:1. 6. The straight-through single-tube solar absorber with a semi-elliptical glass cover according to claim 1, characterized in that: the gap of the thermal insulation layer is a fan-shaped gap, and the thermal insulation layer has an inner arc surface and an outer arc surface, The central angle corresponding to the outer arc surface is 227.4°. 7. The straight-through single-tube solar absorber with a semi-elliptical glass cover according to claim 1, wherein the glass cover is made of ultra-clear glass with a light transmittance above 91.5%. 8. The straight-through single-tube solar absorber with a semi-elliptical glass cover according to claim 1, characterized in that: the outer diameter of the absorber tube is 204 mm, and the inner diameter of the tube is 200 mm.