AN ANALYTICAL MODEL FOR LOCAL HEAT-TRANSFER COEFFICIENTS FOR FORCED CONVECTIVE CONDENSATION INSIDE SMOOTH HORIZONTAL TUBES

An analytical model based on annular flow is proposed for predicting the local heat transfer coefficient for forced convective condensation inside smooth horizontal tubes. The Prandtl mixing length theory, Van-Dreist's hypothesis and Reynolds analogy are used for the analysis. Experiments are conducted by condensing R-22 inside an 8.001 mm (0.315 in.) i.d. copper tube for a wide range of mass flux rates and condensing temperatures. The analytical results, compared with the experimental data and four other correlations reported in the literature indicate that 80% of the predictions are within +/-25% of the experimental data, with a mean deviation of 15.3%.