Numerical Study of Enhanced Heat Transfer and Flow of Water-glycol Mixture in Transversely Ribbed Circular Tubes

摘要

The enhanced heat transfer and flow of water-glycol mixture in transversely ribbed circular tubes was numerically investigated with a 2D axisymmetric model. A pitch long section was chosen and periodic flow with isothermal surface condition within this tube section was computed with Fluent 6.2. The mean friction factor and heat transfer data are obtained. The influence of different rib height and rib pitch on the enhanced heat transfer and flow behavior was studied. The friction factor was well correlated with e/d, p/d and Re with one equation. No critical e/d, which exists for air, was found and the correlation of Nusselt number with Re, e/d, p/d cannot be correlated with similar equations used for air. This could be due to the uncertainty in computation and further experiments are needed to examine this.