DE-13-004 -- An Assessment of Some Predictive Methods for In-tube Condensation Heat Transfer of Refrigerant Mixtures PDF

Condensation heat transfer coefficient of non-azeotropic mixtures is significantly lower than that of single-component fluids due to mass transfer resistances. Several correction factors have been proposed for modifying the predictions of single fluid correlations for use with multicomponent refrigerant mixtures. A comprehensive study evaluating these correction factors against a wide range of experimental data has not been undertaken previously. This research aims at presenting an assessment of such predictive methods to fulfill this need in industry and academia. Analyzable data for miscible mixtures condensing in plain tubes were compared with the predictions of the general correlation of Shah (2009) modified by correction factors proposed by three researchers. The data included 529 test points for 36 refrigerant mixtures from 22 studies in horizontal and vertical tubes and included temperature glides up to 35.5°C (63.9 °F). These were predicted with a mean deviation of 18% using the correction factors of Bell and Ghaly (1973) and McNaught (1979).