A Numerical Study on Determination of the Optimal Hole Diameter and Pitch Value for the Unglazed Transpired Solar Collectors

This investigation is concerned with the unglazed transpired solar collector (solar wall) type. with this purpose, the optimum hole arrangement has been determined by investigating the effect of hole diameter and pitch on the thermal efficiency of the system for different environmental condition. a thermodynamic model is used to simulate the heating process within the system. as a result, for extremely small hole diameters or extremely large hole pitches, the system works as a trombe wall (glazed thermal storage wall) rather than an unglazed transpired solar collector because of the fact that there is not enough air flow through the absorber.