关键词: 太阳能, 高温真空集热管, 真空性能, 老化, 热损

Abstract: This study aims at obtaining vacuum aging mechanism in the annulus of the receiver. Simulating the parabolic trough receiver operation environment, the receivers are heat-treated at 400 ℃ and 450 ℃ to get the variative regulation of the vacuum. The initial vacuum level of the receiver after the degassing process is 4.7×10^-4 Pa at room temperature. After 400 cycles at 400 ℃ and 450 ℃, the pressure of the receiver is 5×10^-3 Pa and 6×10^-2 Pa, respectively. At room temperature, when the normal emission ratio of the absorption coating is 0.08 and the vacuum degree is 10^-3 Pa, the heat loss of the receiver tube is 216 W/m at 400 ℃, showing good thermal performance. The life time of the receiver is about 25 years according to the accelerated aging experiment.

Key words: solar energy, parabolic trough receiver, vacuum property, aging, heat loss