Influence of pentagonal corrugated absorber sheet on heat transfer behavior of solar air collector: numerical analysis with optimized corrugation dimensions

A 2D numerical analysis was executed using ANSYS Fluent 16.0 to optimize the dimensions of pentagonal corrugations (corrugation pitch p and angle α) in the absorber plate of a solar air collector of an indirect solar dryer. Initially, α and corrugation height (e) were kept constant and varied the p from 50 to 175 mm, and optimized p was found. Hence, there are 36 sets of results (part-A). This optimized p was used in the second set of simulations where α is varied from 10° to 37.5° with an increment of 2.5°. It has 72 sets of results (part-B). The performance parameters such as Nusselt number (Nu), friction factor (f), Nu ratio, f ratio and thermohydraulic performance parameter (T_hp) were determined for both sets. Nu ratio was from 1.81 to 3.126, which implied that the heat transfer was enriched up to 3.126 times. The maximum T_hp was 1.748 at p = 150 mm. Hence, p = 150 mm is proposed from part-A simulations. In the part-B simulations, the maximum of T_hp was noticed at α = 35° and 37.5°. Considering the material requirement, dimensions of p = 150 mm and α = 37.5° are proposed.