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ISSN Online: 2377-424X

ISBN CD: 1-56700-226-9

ISBN Online: 1-56700-225-0

International Heat Transfer Conference 13
August, 13-18, 2006, Sydney, Australia

TURBULENCE MODEL HEAT TRANSFER PREDICTIONS IN AN AIR-FILLED SQUARE ENCLOSURE

Get access (open in a dialog) DOI: 10.1615/IHTC13.p6.280
12 pages

Résumé

This work extends previous work by James and Webb (2004) in which four two-equation turbulence models were used to predict heat transfer in a two-dimensional, air-filled square enclosure at a Rayleigh number of 1.58×109 . Predicted data were compared to experimental data of Ampofo and Karayiannis (2003). In general the average Nusselt numbers differed from experiment by about 20% and 5% on the active surfaces (side walls) and passive surfaces (top and bottom walls), respectively. The current work uses two additional turbulence models: Launder-Sharma (1974) low Re k-ε and a k-ε-ν2 (Durbin 1991) to model heat transfer and fluid flow in a square enclosure (x/L = y/L = 1, z/L = 2).
Results show that the low Re Launder-Sharma k-ε model performs worse than the two-equation turbulence models evaluated previously with larger differences in average Nu values on both the active and passive walls. In contrast to the previous models, the near wall velocity predictions were worse indicating that the damping functions are not “tuned” to buoyant flow predictions. The four-equation k-ε-ν2 model predicted average Nusselt values on the active walls to approximately 6% of the experimental values, but on the passive walls predictions were worse with average values about 22% different from experimental data.