High-emissivity low-stagnation-temperature all-glass evacuated collector tube

Abstract

The invention relates to a high-emissivity low-stagnation-temperature all-glass evacuated collector tube. The all-glass evacuated collector tube is made by concentrically connecting a cover glass tube 1 with an inner glass tube 2 to form a jacket and vacuumizing the jacket to form a vacuum heat-insulating layer 3. Ashady face of the outer surface of the inner glass tube 2 comprises an uncoated area 4 provided with a circumferential angle of about 140 degrees and represented by double lines. A film is deposited on the sunny face of the inner glass tube 2. The inner glass tube 2 extends outwards by a section and is sealed to make a heat tube. As shown in figure 1, a working principle is characterized in that sunlight penetrates the cover glass tube 1 to be converted into heat energy on the film of the inner glass tube 2, and the heat energy is outputted through a cold end 5; during normal heat collecting, heat energy radiated through the uncoated area 4 is little; during stagnation, the surface temperature of the inner glass tube 2 is very high, heat energy radiated through the uncoated area 4, with emissivity of 92%, namely, the surface of the inner glass tube 2 is increased, excessive rising of the stagnation temperature is limited, and steam pressure inside the heat tube cannot be too high.

Description

Technical field [0001] The invention relates to an all-glass vacuum heat collecting tube with high emissivity and low air temperature. Background technique [0002] Existing all-glass evacuated heat collection tubes, including heat pipe heat collection tubes made of integrated heat pipe and inner glass tube, have extremely high absorptivity and extremely low emissivity, and can achieve satisfactory heat collection performance and temperature At the same time, the air drying temperature can reach above 230℃. Such a high air temperature will cause the problem of excessively high vapor pressure of the integrated heat pipe working fluid. Summary of the invention [0003] The purpose of the present invention is to provide an all-glass vacuum heat collecting tube with high emissivity and low air temperature. [0004] The technical solution adopted by the present invention to solve the technical problem: the cover glass tube and the inner glass tube are concentrically sealed to form an ...

AI Technical Summary

Problems solved by technology

Such a high air drying temperature will cause the problem of excessive vapor pressure of the integrated heat pipe

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