An Analysis of Film Condensation, Film Evaporation, and Single-Phase Heat Transfer for Liquid Prandtl Numbers From 10−3 to 104

Abstract

Annular two-phase flow inside of circular tubes is analyzed for a wide range of film Reynolds and Prandtl numbers. This analysis is applied to the prediction of film heat transfer coefficients and film thicknesses for the cases of condensation and evaporation of pure substances inside tubes, two-component flow in tubes, and condensing falling films on vertical surfaces. The analysis is also extended to single-phase flow in tubes. Extensive comparisons are made with experimental and theoretical results of other investigators, indicating good agreement if consideration is given to liquid-vapor interfacial resistance to heat flow for cases involving phase transformation.