Efficiency Analysis in Solar Air Heaters with Attached Internal Fins

Abstract

In this study, an original solar air collector model, those of flow environment was fixed with fins for three different angles at the flow channel's height, was designed. Fixing fins in the flow environment lengthens the flow channel since the fins prevent boundary layer formation in a flow cannel. Apart from this, enlarged surface effect exists along with the effects of the fins, the air temperature at the outlet rises. The effects of fixed fins,for 30°, 45° and 60° angles, on the efficiency of collector were investigated. The collectors were made as standard collectors sets with measurements 0.93x1.93 m2 the flow channels of which have been modified. With the help of results obtained from the experiments, efficiency, Nusselt number, Reynold number values were calculated; and they were compared to each other along with the literature. In the collectors designed for this study, it was observed that the heat transfer increased with the decrease of the fins angles.

Keywords

• Solar air heater
• Exergy loss
• Efficiency
• Heat transfer

References

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