Optimization analysis of the length of baffles for solar air heaters based on CFD

Incorporating baffles was demonstrably efficacious in augmenting the functionality of solar air heaters (SAHs). A duly validated mathematical model is formulated for SAHs with baffles, aimed at the optimization of baffle length (L-b). Our findings demonstrated that with air velocity (v) spanning from 0.5 to 3.0 m center dot s(-1) and baffle length (L-b) varying between 150 and 750 mm, a discernible rise in pressure loss ensued. This phenomenon is ascribed to the extension of baffles, resulting in escalated air velocity and heightened vortex intensity. In the range of v = 0.5 similar to 3.0 m center dot s(-1), the collection efficiency evinced a marked surge by 4.61% to 11.32% when L-b traversed from 150 to 450 mm, while the collection efficiency tended to be constant as L-b exceeded 450 mm. A holistic evaluation of both pressure loss and heat collection efficiency culminates in the deduction that the pinnacle of operational effectiveness, measuring 60.78%, was attained at Lb = 600 mm and v = 3.0 m center dot s(-1). The economic scrutiny of baffled SAHs unveiled a Coefficient of Useful Energy (Cue) of a mere 0.057y center dot kwh(-1), notably inferior to that resultingensuing from the incineration of fossil fuels under the conditions of v = 3.0 m center dot s(-1) and Lb = 600 mm.