Differential exergy investigation and environ-economic assessment of a dimpled plate and flat plate solar air heater under turbulent conditions

The current investigation explores the performance of a spherical dimple solar air heater (D-SAH) within the framework of the Second Law of Thermodynamics under turbulent conditions. This analysis considers component -wise exergy potential losses, their differentials, and the overall exergy efficiency (?Ex). Given the inherently entropic nature of turbulent flow, an evaluation is conducted to determine the limiting mass flow rate (MFR). To ensure long-term adaptability and a comprehensive understanding of the designed solar air heater (SAH), various matrices, including economic, environmental, environ-economic, exergo-economic, and energy, are assessed across four service life scenarios. The obtained results are benchmarked against those of a flat plate solar air heater (F-SAH). Exergetic analysis is conducted for six different MFRs on different days, revealing absorption losses as the most influential exergy losses. D-SAH incurs 3.99% higher absorption losses, leading to a lower ?Ex. The design is deemed suitable for MFR 0.028 kg/s. The impact of higher Reynolds number (Re) and the temperature rise parameter (TRP) results in a decrease in ?Ex for both SAHs. Specifically, D-SAH shows a 71% reduction in ?Ex as Re increases from 5684 to 10,352. However, D-SAH exhibits promising performance in terms of CO2 mitigation and carbon credits earned, surpassing F-SAH by 27.89% to 23.38%. Furthermore, these performance metrics increase by 50% when extending the service life from 20 years to 30 years. Statistical correlation and the coefficient of determination authenticate these findings.