Condensation of steam in the presence of air in vertical tubes

Includes bibliographical references (pages 45-49)Experimentation was carried out to determine the effect of variations in the mass fraction of air present, the Reynolds number, and tube dimensions on condensation rates for downward laminar flow in vertical tubes. To generate data, an apparatus was built to meter air and superheated steam into short, cooled lengths of copper tube whose inner wall temperatures were measured by thermocouples. Condensate was collected from the tubes, and the amount collected was compared to the amount expected based on the classical relationship derived by Nusselt. These results were then compared to the results provided by finite difference solutions of the equations which govern this phenomenon. Mathematical relationships for the rate of condensation normalized to Nusselt's results were derived