Tilted honeycombs for optimal collector covers
Geneigte Wabenstrukturen als optimale Kollektorabdeckung
Tilting honeycomb structures in principle provides a cheap way of improving as well heat resistance as solar transmittance of collector covers. Monthly average transmittance for different orientations may be increased when compared to vertical honeycombs VHC (Platzer, 1988 and Zhao, 1989). Other configurations achieve low transmittance during the summer combined with large winter transmittance (Platzer, 1989). From experimental values it could be shown, that the heat resistance increases with tilt angle due to the reduced radiation transport (Platzer, 1988). In this paper results from a theoretical model for solar transmittance and heat transport of tilted honeycombs THC are compared with experimental values. Although some simplifications are inherent in the models, the comparison is quite satisfactory.