Upgrading the performance of a solar air collector with flexible aluminum air ducts and graphene nanoplatelet-enhanced absorber coating

• Published in: Thermal science and engineering progress Vol. 40; p. 101760
• Main Authors: Öztürk, Murat, Çiftçi, Erdem
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2023
• Subjects: Flexible air ducts; Graphene nanoplatelet; Performance enhancement; Solar air collector; Sustainability index; Waste exergy ratio; Graphene nanoplatelet; Performance enhancement; Sustainability index; Flexible air ducts; Solar air collector; Waste exergy ratio
• ISSN: 2451-9049; 2451-9049
• DOI: 10.1016/j.tsep.2023.101760

Solar air collectors (SAC) have had great importance nowadays as far as clean energy production is concerned. In this study, the novel double flow solar air collectors were designed and their performance was investigated. This study aims to illustrate how affect the thermal performance and sustainability indicators of a newly-designed solar air heater with nano-enhanced aluminum air ducts instead of conventional sheet metal absorber plate. Two double flow solar air collectors, the former of which includes flexible aluminum air ducts coated by black matte paint (DSAC/FAD), whereas the latter one includes sheet metal plate coated by black matte paint (DSAC) were studied under the same environmental conditions. Moreover, the effect of nanoparticles on performance was investigated by adding nanoparticles into the paint. For this purpose, a set of experiments were simultaneously performed utilizing solar air collector with flexible aluminum air ducts coated with black matte paint (DSAC/FAD) and the double flow solar air collector with flexible aluminum air ducts coated with graphene nanoplatelet-included black matte paint (DSAC/NFAD). The experiments were conducted with the same fans of 40 W power. The energy, exergy and such sustainability indicators as waste exergy ratio (WER) and sustainability index (SI) were examined for each design. In the second part of experiments, the maximum thermal efficiency was obtained as 73.94% for the (DSAC/NFAD). The COP values for DSAC (Day 1), DSAC/FAD (Day 1), DSAC/FAD (Day 2), and DSAC/NFAD (Day 2) were found as 4.82, 4.52, 4.56, and 5.22, respectively. Similarly, the mean exergy efficiency of the (DSAC/NFAD) was calculated as 37.73%, whilst DSAC had the mean exergy rate of 17.93%. For the sustainability indicators, the best results of WER and SI were achieved in the experiments conducted on DSAC/NFAD. It was concluded that the double flow solar air collector with flexible aluminum air ducts can be utilized for thermal performance enhancement. Moreover, it is predicted that the outcomes of this study enlightened the new research topics to be emerged.