摘要
由于对太阳能集热器面积定义的不统一,当用不同的面积进行计算时,造成了同一台集热器得到不同瞬时效率方程的结果,因此,不能真实地反映集热器热性能的优劣,甚至会引起用户误解。文章以全玻璃真空管集热器和U型管CPC集热器的测试为基础,对测试数据进行了效率和能量方程的拟合与计算,每台集热器只得到唯一的能量方程和曲线;并且,能量方程仅与太阳总辐照度G和集热器进口温度与环境温度之差(ti-ta)有关,与集热器面积无关,避免了计算面积对集热器性能曲线的影响。用能量方程来表示集热器的热性能更合理,建议将其纳入相关标准中,以准确表征集热器的热性能。
The instantaneous efficiency equation of the solar collector could be expressed in different ways that depends on different presentation of collector area. As a resultl the thermal performance of the solar collector could not be reflected actually, meanwhile, the users are usually misguided. In order to solve the problem, in this paper, another expression for reflecting the thermal performance of the solar collector is proposed and is verified by testing the thermal performance of the vacuum glass tube solar collectors and the U-tubular vacuum tube CPC solar collectors. According to the test data, the Least Squares Fitting for the instantaneous efficiency and energy equation of collector are calcu- lated. The calculation results show that energy equation and energy curve of each collector are unique. The influence factors of energy equation are just the gross solar irradiance and the differential temper- ature of the inlet temperature and the ambient temperature, there is no any influence from the collec- tor area. Therefore, it is proposed that the power equation and the power curve should be adopted in interrelated standards to reflect the thermal performance of solar collector accurately.
出处
《可再生能源》
CAS
北大核心
2010年第5期15-18,共4页
Renewable Energy Resources
关键词
太阳能集热器
瞬时效率
能量方程
能量曲线
solar collector
instantaneous efficiency
power equation
power curve
