A study of internal forced convective boiling heat transfer for binary mixtures

Over 1,100 data points for internal forced convective boiling heat transfer are reported. Most of these data were taken in the annular flow regimes. The fluids tested were distilled water, ethylene glycol and aqueous mixtures of ethylene glycol. The experimental data indicates the following: (1) a previously unrecognized Prandtl number effect for both pure components and mixtures; (2) a mixture effect associated with the microscopic heat transfer mechanism; and (3) a mixture effect associated with the macroscopic heat transfer mechanism. An expression is developed which correlates the experimental data to within a mean deviation of 14.9%. A modified Reynolds analogy is used which accounts for the Prandtl number effect. It is postulated that the mixture effects observed for this study are due to local composition profiles in the liquid, near the evaporating layer.