Design curves for conventional solar air heaters

The objective of this work is to assess the combined effects of fixed pressure drop and specific air mass flow rate on duct dimensions (length and depth) of single-pass-with-bare-plate, single-cover and double-cover solar air heaters, and to obtain the resultant system efficiency that corresponds to a pre-fixed pumping cost and a minimum material cost per unit area of the system. The design selection methodology adopted in this paper will make it feasible for an air-heater designer to construct efficient and economical solar air heaters.