DOI: 10.1615/ICHMT.2004.CHT-04
ISBN Print: 978-1-56700-174-7
ISSN: 2578-5486
EVALUATION OF AN APPROXIMATE METHOD FOR PREDICTING THE U-VALUE OF A WINDOW WITH A BETWEEN-PANES LOUVERED SHADE
ABSTRAKT
A numerical model has been developed of the conjugate convection, conduction and radiation heat transfer in a double glazed window with a between-panes venetian-type blind. The two-dimensional finite-volume model has been validated for a range of slat angles using U-Value measurements from the open literature. This "Full CFD Model" has been used to show that the thermal performance of the window/blind enclosure can be closely approximated using a much simpler model. The "Simplified Model" combines data from a convection-only CFD solution with a six-surface radiation model. For both standard (high-e) and low-e windows, it has been shown that the Simplified Model can predicted the U-Value of the window/blind enclosure to within 1.5 percent, compared to the Full CFD Model. It has also been shown that the Simplified Model can account for geometric effects, such as the blind being located off the centre line of the gas-filled enclosure. Air was the fill gas in all calculations.