CFD analysis of solar air collector equipped with flexible ribs

In this paper a new concept via the use of flexible ribs to control flow and heat transfer inside the air duct of a solar air collector is proposed. The new model uses flexible ribs instead of conventional fixed ribs, to improve the control efficiency and, therefore, to seek better energy extraction performance. The effect of flow mass rates on flow and heat transfer behavior has been investigated. It is apparent that the turbulence generated by flexible ribs provides a greater increase in heat transfer over the air duct. Results show also that the thermal enhancement factor tends to increase with the rise of Reynolds number where the highest value of this factor is registered for the flexible ribs configuration.