Heat transfer coefficients for Freon-12 condensing within a horizontal tube

Abstract

The purpose of this investigation was to continue the study begun by Crosser (5) of heat transfer coefficients for condensing vapors in a horizontal tube. Condensing heat transfer coefficients for Freon-12 were measured over a wide range of vapor velocities, fluid properties, and temperature differences. Using an analogy to one-phase flow, the following equation was derived for the region where the film of condensed liquid is annular and turbulent: [formula handwritten] It was found that the data could be correlated over the entire range of vapor velocity if the group [handwritten text] were plotted versus the Reynolds. number, [handwritten text]. The slope of the line through the data varied from approximately .2 at low Reynolds number to the .8 value at Reynolds numbers above 2 x 104. The excellent agreement of data from different pressures and temperature differences indicate that the density ratios [handwritten text] adequately expresses the effect of liquid loading.