CN210892197U

CN210892197U - Vacuum heat collecting tube for solar hot air system

Info

Publication number: CN210892197U
Application number: CN201921720620.7U
Authority: CN
Inventors: 朱晓东; 孟祥�; 丁伟; 许国; 崔巍; 许星
Original assignee: Zhejiang Yulu New Energy Technology Co ltd
Current assignee: Zhejiang Yulu New Energy Technology Co ltd
Priority date: 2019-10-14
Filing date: 2019-10-14
Publication date: 2020-06-30
Anticipated expiration: 2029-10-14

Abstract

The utility model provides a solar thermal energy air-collecting system uses evacuated collector tube, includes glass inner tube and glass outer tube, and the glass inner tube is including air inlet section, spiral coil pipe section, changeover portion, the heavy-calibre heat transfer section that links together in proper order, and air inlet section outer end and the sealed butt fusion of glass outer tube, the outer end and the sealed butt fusion of glass outer tube of heavy-calibre heat transfer section, air inlet section and the coincidence of the central line of heavy-calibre heat transfer section, changeover portion and glass outer tube inboard bottom scribbles reflective coating. The spiral coil pipe section is arranged, so that the air flow which just enters the glass inner pipe can be preheated, and the phenomenon that the temperature difference between the air flow and the glass inner pipe is large to cause pipe explosion is prevented; the spiral coil pipe section has elasticity, and can offset stress generated by temperature difference.

Description

Vacuum heat collecting tube for solar hot air system

Technical Field

The utility model belongs to the technical field of solar collector, a vacuum heat collecting tube for solar hot-air system is related to.

Background

Most of solar hot air vacuum heat collecting tubes in the prior art are in one-way conduction, namely, the upper end of an outer tube is sealed with the upper end of an inner tube, the lower ends of the inner tube and the outer tube are both sealed, and a cavity formed between the inner tube and the outer tube is used for pumping and exhausting air to form vacuum. The water accumulated in the inner pipe can not be discharged when the water-saving water dispenser is used, so that the water can deteriorate after long-term use, a large amount of pollutants are accumulated in the pipe, the water quality is poor, and the water-saving water dispenser is unsanitary. For changing quality of water, people have designed the thermal-collecting tube of inside and outside, upper and lower through connection, but because the difference in temperature is very big between inside and outside pipe during the use, when vacuum thermal-collecting tube heaies up to more than 100 ℃, the inner tube can be heated the inflation, and the outer tube does not expand simultaneously to the power that the inner tube inflation made the pipe produce extends to the outer tube: the upper end and the lower end of the inner pipe and the outer pipe are connected together, so that the pipe is fried.

For example, the application document with the Chinese patent application number of 200820170566.9 discloses a straight-through solar vacuum heat collecting tube, which comprises an outer tube, an inner tube, a fixing clip, a degassing sheet, a vacuumizing tail tube and a corrugated tube made of metal, wherein one end of the corrugated tube is welded with the outer tube, and the other end of the corrugated tube is welded with the inner tube. The utility model has the advantages of reasonable design, can overcome the stress that inner tube and outer tube junction produced to evacuated collector tube fried pipe that bursts because of stress has been avoided. However, when the air inlet temperature of the vacuum heat collecting tube with the built-in corrugated tube is low, the air speed is too high, so that the heat exchange tube at the rear end is easy to contact low-temperature air, and the tube explosion caused by large temperature difference is caused.

SUMMERY OF THE UTILITY MODEL

The utility model aims at having the above-mentioned problem to current technique, provided a solar thermal energy is evacuated collector tube for air-conditioning system, set up the spiral coil section and preheat the air current, can prevent effectively that the difference in temperature is big and the booster in the heavy-calibre heat transfer section.

The purpose of the utility model can be realized by the following technical proposal: the utility model provides a solar thermal energy air-collecting system uses evacuated collector tube, includes glass inner tube and glass outer tube, its characterized in that, glass inner tube is including air inlet section, spiral coil section, changeover portion, the heavy-calibre heat transfer section that links together in proper order, and air inlet section outer end and the sealed butt fusion of glass outer tube, the outer end and the sealed butt fusion of glass outer tube of heavy-calibre heat transfer section, air inlet section and the central line coincidence of heavy-calibre heat transfer section, changeover portion and glass outer tube inboard bottom scribbles reflection of light coating.

The working principle of the evacuated collector tube is that solar energy can irradiate the heat absorber on the outer surface of the inner glass tube through the outer glass tube and is converted into heat energy, then the air flow in the inner glass tube is heated, and the heat loss to the surrounding environment is effectively reduced due to the fact that the interlayer is vacuumized, and the heat collection efficiency is improved. The air flow enters from the air inlet section, is preheated by the spiral coil pipe section and finally enters the large-caliber heat exchange section for heat exchange. The inner side of the glass outer tube is coated with the reflective coating, so that sunlight can be reflected to the glass inner tube, and the utilization rate of solar energy is further improved.

Furthermore, the diameters of the air inlet section and the spiral coil pipe section are 9-11 mm.

Furthermore, the diameter of the large-caliber heat exchange section is 45-48mm, and the diameter of the glass outer tube is 57-60 mm.

Furthermore, the length of the glass outer tube is 180cm, and the length of the large-caliber heat exchange section is 160 cm and 170 cm.

Further, the thickness of the outer glass tube and the inner glass tube is 1.5-1.8 mm.

Furthermore, the light reflecting coating is positioned below the large-caliber heat exchange section. The reflecting coating is preferably reflecting paint which is prepared by mixing acrylic resin serving as a base material and a certain proportion of directional reflecting materials in a solvent, and belongs to novel reflecting paint.

Furthermore, the welding position of the glass outer tube and the air inlet section is provided with an air exhaust tail end. And after the exhaust tail end is welded well between the glass outer tube and the glass inner tube, the internal gas is exhausted to form vacuum, and finally the glass inner tube is blocked.

Compared with the prior art, the vacuum heat collecting tube for the solar hot air system has the following advantages:

1. the heat exchanger has a large-diameter heat exchange section, a large heat exchange area and a good heat exchange effect;

2. the spiral coil pipe section is arranged, so that the air flow which just enters the glass inner pipe can be preheated, and the phenomenon that the temperature difference between the air flow and the glass inner pipe is large to cause pipe explosion is prevented; the spiral coil pipe section has elasticity, and can offset stress generated by temperature difference.

3. The inner wall of the glass outer tube is coated with a reflective coating, so that the solar energy utilization rate is improved.

4. The air inlet section is superposed with the central lines of the large-diameter heat exchange section, the transition section and the glass outer tube, and the sealing performance is good.

Drawings

Fig. 1 is a schematic structural view of the evacuated collector tube for a solar hot air system.

In the figure, 1, an outer glass tube; 11. exhausting the tail end of the gas; 2. an air inlet section; 3. a helical coil section; 4. a transition section; 5. a large-diameter heat exchange section; 6. a light reflecting coating.

Detailed Description

The following are specific embodiments of the present invention and the accompanying drawings are used to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

As shown in fig. 1, the vacuum heat collecting tube for the solar hot air system comprises a glass inner tube and a glass outer tube 1, and is characterized in that the glass inner tube comprises an air inlet section 2, a spiral coil section 3, a transition section 4 and a large-diameter heat exchange section 5 which are sequentially connected together, the outer end of the air inlet section 2 is hermetically welded with the glass outer tube 1, the outer end of the large-diameter heat exchange section 5 is hermetically welded with the glass outer tube 1, the air inlet section 2 is superposed with the central lines of the large-diameter heat exchange section 5, the transition section 4 and the glass outer tube 1, a reflective coating 6 is coated at the bottom of the inner side of the glass outer tube 1, and the reflective coating 6 is positioned below the large-diameter heat.

The working principle of the evacuated collector tube is that solar energy can irradiate the heat absorber on the outer surface of the inner glass tube through the outer glass tube and is converted into heat energy, then the air flow in the inner glass tube is heated, and the heat loss to the surrounding environment is effectively reduced due to the fact that the interlayer is vacuumized, and the heat collection efficiency is improved. The air flow enters from the air inlet section 2, is preheated by the spiral coil pipe section 3 and finally enters the large-diameter heat exchange section 5 for heat exchange. The inner side of the glass outer tube 1 is coated with the reflective coating 6, so that sunlight can be reflected to the glass inner tube, and the utilization rate of solar energy is further improved.

The diameters of the air inlet section 2 and the spiral coil section 3 are 9-11mm, the diameter of the large-diameter heat exchange section 5 is 45-48mm, the diameter of the glass outer tube 1 is 57-60mm, the length of the glass outer tube 1 is 180cm, the length of the large-diameter heat exchange section 5 is 160-170cm, and the thicknesses of the glass outer tube 1 and the glass inner tube are 1.5-1.8 mm.

The spiral coil section 3 mainly has two functions: one, owing to receive the shining of sunlight, the difference in temperature of glass inner tube and glass outer tube 1 is very big, and the temperature of glass inner tube can reach more than 200 ℃ even when empty shining, and the glass inner tube at this moment just can be heated in its length direction and expand: due to the fact that the spiral coil pipe section 3 is arranged, the expansion amount of the glass inner pipe can be adjusted through the spiral coil pipe section 3, and therefore the vacuum heat collecting pipe is prevented from exploding due to stress generated by the temperature difference of the glass inner pipe and the glass outer pipe 1. Secondly, the air flow passing speed is reduced, so that a certain preheating effect can be provided for the air flow in the spiral coil pipe section 3, and if the spiral coil pipe section 3 is not available, the low-temperature air flow directly enters the high-temperature large-caliber heat exchange section 5 to explode.

And an exhaust tail end 11 is arranged at the welding position of the glass outer tube 1 and the air inlet section 2. And after the glass outer tube 1 and the glass inner tube are welded, the exhaust tail end 11 pumps out the internal gas to form vacuum, and finally, the glass inner tube is blocked.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Claims

1. The utility model provides a solar thermal energy air-collecting system uses evacuated collector tube, includes glass inner tube and glass outer tube, its characterized in that, glass inner tube is including air inlet section, spiral coil section, changeover portion, the heavy-calibre heat transfer section that links together in proper order, and air inlet section outer end and the sealed butt fusion of glass outer tube, the outer end and the sealed butt fusion of glass outer tube of heavy-calibre heat transfer section, air inlet section and the central line coincidence of heavy-calibre heat transfer section, changeover portion and glass outer tube inboard bottom scribbles reflection of light coating.

2. The evacuated collector tube for a solar thermal energy wind system according to claim 1, wherein the diameters of the air inlet section and the spiral coil section are 9-11 mm.

3. The evacuated collector tube for a solar thermal energy wind system according to claim 1, wherein the diameter of the large-caliber heat exchange section is 45-48mm, and the diameter of the glass outer tube is 57-60 mm.

4. The evacuated collector tube for a solar thermal air system as defined in claim 1, wherein the length of the glass outer tube is 180cm, and the length of the large-caliber heat exchange section is 160 and 170 cm.

5. The evacuated collector tube for a solar thermal energy wind system according to claim 1, wherein the thickness of the glass outer tube and the glass inner tube is 1.5-1.8 mm.

6. The evacuated collector tube for a solar thermal energy wind system according to claim 1, wherein the reflective coating is located below the large caliber heat exchange section.

7. The evacuated collector tube according to claim 1, wherein an exhaust tail end is provided at a welding position of the glass outer tube and the air inlet section.