Enhancing thermal efficiency of double-pass solar air collectors: A comparative study on the role of V-angled perforated fins

This study investigates the enhancement of thermal efficiency in double-pass solar air collectors (DPSACs) by incorporating V-angled perforated fins. It compares the performance of a finned model (FDPSAC) with a conventional smooth model, aiming to optimize thermal efficiency through improved heat transfer and air distribution. The experiments were conducted under three airflow rates: 0.00864 kg/s (Case I), 0.01143 kg/s (Case II), and 0.01317 kg/s (Case III). The findings indicated that the FDPSAC significantly outperformed the DPSAC, achieving higher outlet temperatures and demonstrating superior heat gain. The daily efficiency for the FDPSAC was 51.6 %, 54.7 %, and 59.2 %, exceeding the DPSAC, which were 49.4 %, 50.5 %, and 53.9 % for cases I, II, and III, respectively. The daily collector efficiency of the FDPSAC improved by approximately 4.45 %, 8.32 %, and 9.83 % relative to the DPSAC for the same case order. The results also showed that the FDPSAC maintained lower temperatures of the absorber plate, suggesting more effective heat dissipation and overall system efficiency. This study highlights the critical role of innovative fin design and optimal airflow management in enhancing solar collector performance. These improvements highlight the potential of the proposed fins to enhance solar air collector efficiency, providing key insights for optimizing thermal systems in sustainable energy.