Experimental study on the thermal performance and pressure drop of a solar air collector based on flat micro-heat pipe arrays

• Published in: Energy conversion and management 2015-04, Vol.94, p.447-457
• Main Authors: Zhu, Ting-ting, Diao, Yan-hua, Zhao, Yao-hua, Deng, Yue-chao
• Format: Article
• Language: English
• Subjects: Accumulators; Airflow; Arrays; Collectors; Flat micro-heat pipe arrays; Pipe; Pressure drop; Solar air collector; Thermal efficiency; Thermal properties
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2015.01.052

•A new type of solar air collector by using flat micro-heat pipe arrays is proposed.•Thermal efficiency rates in summer and winter are approximately 73% and 56%.•The pressure loss is below 25Pa when the volume flow rate is less than 201.6m3/h. A new solar air collector that combines the use of flat micro-heat pipe arrays (FMHPA) and evacuated tube is developed and investigated. Using FMHPA as the central transporting component in a solar air collector is an effective approach to improve the collector’s thermal properties and reduce its pressure drop. The thermal properties and pressure drop of the FMHPA solar air collector are analyzed in detail. The main objective of this paper is to report test results of the FMHPA solar air collectors which includes the effects of different seasons and airflow rates on the thermal efficiency and the pressure drop of the air collector. In summer, the thermal efficiency of the collector reaches 73% under stable operation. In the testing airflow range condition, the pressure drop is less than 25Pa when the flow rate is below 201.6m3/h. The relative uncertainty of thermal efficiency is approximately 7.73%.