CN204478530U - A kind of Dual-layer optical window structure solar heat absorber - Google Patents

Abstract

The utility model discloses a kind of Dual-layer optical window structure solar heat absorber, comprise heat-insulation layer and housing, described hull outside is enclosed with heat-insulation layer, and described case inside is high temperature endothermic surface; Described shell nozzle place is inlaid with the quartz-optical window reducing heat loss, described quartz-optical window innermost insert has the sapphire optical window preventing quartz-optical window from breaking, described sapphire optical window and housing form the heat-absorbing chamber sealed, and form the heat-insulation chamber of sealing between quartz-optical window and sapphire optical window.The utility model takes into account the heat dump thermal efficiency and functional reliability, improves the practical generalization of solar heat absorber.

Description

A double-layer optical window structure solar heat absorber

technical field

The utility model relates to a solar heat absorber, in particular to a solar heat absorber with a double-layer optical window structure.

Background technique

The heat-absorbing surface temperature of solar high-temperature heat conversion is high, and the loss of radiation and convection heat dissipation is large. The use of optical windows to separate the heat-absorbing surface from the surrounding atmosphere to form a volumetric solar heat absorption and eliminate the convective heat dissipation loss of the heat-absorbing surface is a key technical approach to improve the high-temperature heat conversion efficiency of solar energy. Quartz and sapphire are two important high-temperature optical window materials for solar energy. Quartz windows are characterized by high sunlight transmittance (about 90%), but they are brittle and easy to break, and their working temperature is not high (devitrification temperature is about 1000°C). . According to our previous experiments, the optical window is easy to break during the extrusion sealing process before the experiment. Under the high temperature condition of solar radiation, the optical window is more likely to be broken due to the high temperature deformation of the supporting flange, resulting in the quartz optical window. work reliability is poor. The sapphire optical window has a high melting point (about 3500°C), no devitrification phenomenon, excellent high-temperature mechanical properties, stable chemical properties but slightly low solar light transmittance (about 80%).

At present, the focus of existing heat sinks is on the internal structure design of the heat sink, and little attention has been paid to the optical window of the heat sink. For example, patent 201110233330.1 discloses a solar heat absorber with a convex cylindrical cavity on the bottom surface of the bottom surface of the heat absorber shell in a V-shaped structure; A single-sided multi-longitudinal vortex enhanced heat exchange focusing trough solar heat absorber with raised or recessed discontinuous multi-longitudinal vortex generators; patent 201110255144.8 discloses a spherical cavity solar heat absorber with a concave glass cover, It is mainly composed of heat exchange coil, inner concave glass cover, outer shell, inner shell, vacuum layer, reflective windshield and heat transfer fluid. Patent 201210056836.4 discloses a cylindrical and conical composite cavity type solar heat absorber in which the inner cavity of the shell is a cylindrical and conical composite cavity. Patent 201310041996.6 discloses a high-efficiency solar heat absorber based on a light-heat absorption cone configuration with a pyramid-shaped structure and each plane can be manufactured separately. Patent 201220412104.X discloses a serpentine corrugated tube solar heat absorber in which a metal corrugated inner tube is bent into a serpentine shape by a single metal corrugated tube. Patent 201220612985.X discloses a cavity-type solar heat absorber whose bottom of the shell is a curved hemisphere.

Utility model content

In view of the above-mentioned present situation, the utility model combines the characteristics of high sunlight transmittance of quartz optical windows and firm texture of sapphire optical windows, and proposes a solar heat absorber with double-layer optical window structure of quartz optics and sapphire optics, which takes into account the thermal efficiency of the heat absorber and the The work reliability is improved, and the practical popularization of the solar heat absorber is improved.

For realizing the above object, the technical scheme of the utility model is:

A solar heat absorber with a double-layer optical window structure, including an insulation layer and a casing, the outside of the casing is wrapped with an insulation layer, and the inside of the casing is a high-temperature heat-absorbing surface; the opening of the casing is inlaid with a heat-reducing Lost quartz optical window, the inner side of the quartz optical window is inlaid with a sapphire optical window to prevent the quartz optical window from breaking, the sapphire optical window forms a sealed heat-absorbing cavity with the housing, and a seal is formed between the quartz optical window and the sapphire optical window insulation cavity.

In a further technical solution, the thickness of the quartz optical window is 1-2 mm, and the thickness of the sapphire optical window is 2-5 mm.

In a further technical solution, the quartz optical window and the sapphire optical window are planar structures. The utility model has the following advantages:

1. Due to the high-temperature melting point of sapphire (about 3500°C) and excellent mechanical properties, a high-pressure, high-temperature heat-absorbing cavity is formed by using the inner sapphire optical window and the high-temperature heat-absorbing wall surface, and the system has high safety and reliability;

2. The high-temperature sapphire window is separated from the surrounding atmospheric environment through the outer quartz optical window, which is beneficial to reduce the convection and radiation heat loss of the sapphire optical window and improve the thermal efficiency of the system; the sealed isolation formed between the quartz optical window and the sapphire optical window Thermal cavity further reduces heat loss;

3. Fully consider the characteristics of high sunlight transmittance of quartz optical windows, but brittle and easy to break. Through the double-layer optical window design, the outer quartz optical window does not bear any pressure, which has better safety and reliability.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described:

Fig. 1 is a schematic diagram of an embodiment of the utility model.

Among them: 1. Insulation layer; 2. Housing; 3. Quartz optical window; 4. Sapphire optical window; 5. Heat absorption chamber; 6. Heat insulation chamber.

Detailed ways:

Example

A solar heat absorber with a double-layer optical window structure as shown in Figure 1, including an insulation layer 1 and a casing 2, the outside of the casing 2 is wrapped with an insulation layer 1, and the inside of the casing 2 is a high-temperature heat-absorbing surface The opening of the housing 2 is inlaid with a quartz optical window 3 that reduces heat loss, and the inside of the quartz optical window 3 is inlaid with a sapphire optical window 4 that prevents the quartz optical window 3 from breaking, and the sapphire optical window 4 and the housing 2 A sealed heat-absorbing chamber 5 is formed, and a sealed heat-insulating chamber 6 is formed between the quartz optical window 3 and the sapphire optical window 4 .

The quartz optical window 3 has a thickness of 1-2 mm, and the sapphire optical window 4 has a thickness of 2-5 mm, both of which are planar structures.

Its working process is shown in Figure 1. At the sunlight entrance of the heat absorber, there are two layers of optical windows, quartz optical window 3 glass and sapphire optical window 4, arranged in sequence. The concentrated sunlight passes through the quartz optical window 3 and the sapphire optical window 4 in sequence, and finally enters the heat-absorbing cavity 5 to complete the light-to-heat conversion. The sapphire optical window 4 is extruded and sealed with the housing 2 to form a high-pressure, high-temperature heat-absorbing cavity 5 . The sapphire optical window 4 bears the high-pressure stress and high-temperature infrared radiation of the heat-absorbing cavity 5 , and thus bears high heating thermal stress and high working temperature. The quartz optical window 3 is arranged outside the sapphire optical window 4 to form a thermal insulation cavity 6 to isolate the sapphire optical window 4 from the external atmosphere, reducing the radiation and convection heat loss of the high temperature sapphire optical window 4 .

Through the double-layer optical window design, the outer quartz optical window 3 does not bear any pressure and has better safety and reliability. If only one layer of sapphire optical window 4 is used, its thermal efficiency is not as good as that of a double-layer optical window structure heat absorber; if only one layer of quartz optical window 3 is used, its safety and reliability is not as good as that of a double-layer optical window structure heat absorber.

The above-mentioned embodiments are only described as preferred implementation modes of the utility model, and are not intended to limit the scope of the utility model. Under the premise of not departing from the design spirit of the utility model, technical solutions of the utility model are made by those of ordinary skill in the art. Various modifications and improvements should fall within the protection scope determined by the claims of the present utility model.

Claims (3)

1. a Dual-layer optical window structure solar heat absorber, comprise heat-insulation layer (1) and housing (2), it is characterized in that, described housing (2) outside is enclosed with heat-insulation layer (1), and described housing (2) inner side is high temperature endothermic surface; Described housing (2) opening part is inlaid with the quartz-optical window (3) reducing heat loss, described quartz-optical window (3) innermost insert has the sapphire optical window (4) preventing quartz-optical window (3) from breaking, described sapphire optical window (4) and housing (2) form the heat-absorbing chamber (5) sealed, and form the heat-insulation chamber (6) of sealing between quartz-optical window (3) and sapphire optical window (4).

2. Dual-layer optical window structure solar heat absorber as claimed in claim 1, it is characterized in that, quartz-optical window (3) thickness is 1-2mm, and sapphire optical window (4) thickness is 2-5mm.

3. Dual-layer optical window structure solar heat absorber as claimed in claim 1, it is characterized in that, quartz-optical window (3) and sapphire optical window (4) are planar structure.