A thermal performance comparative analysis of solar air heater with a flat absorber plate and fins addition is carried out. The total area of the absorber plate was increased by adding different geometric shapes: rectangular, triangular and cylindrical fins. Heat transfer was studied by free and forced convection with an air mass flow of 0.033 kg/s. The behavior of the air outlet temperature as a function of time in the flat absorber plate shows that the highest air outlet temperature values correspond to the solar collector cylindrical with fins, the Ts2 value highest was 73°C. The thermal performance of solar air heaters with flat absorber plate and fins, without forced air flow, recorded maximum values with cylindrical fins on the absorber plate, reaching results of ɳ2=35% for solar radiation values of . The thermal performance with the use of triangular fins achieves the lowest results, ɳ3=35%.
Enrique et al. (Fri,) studied this question.