Refrigerant forced-convection condensation inside horizontal tubes

Condensing heat transfer rates inside a horizontal tube were investigated-for large quality changes across the tube. The proposed correlation is a modification of the work of Rohsenow, Webber and Ling [29]. The result of the investigation is modified through new variables which include the effect of the true axial pressure gradient in a tube. Experimental data are presented for a range of flow conditions. A 0.493 in. ID, 19.75 ft. long nickel tube was used for condensing Refrigerant-12. The saturation temperature was varied from 84.6*F to 118*F and flow rates of vapor-liquid mixture ranged from 151,000 lbm/ft 2hr to 555,000 lbm/ft 2hr. The inlet quality was essentially 100 % at saturation and exit qualities ranged from 50 % to zero and subcooled liquid. The test results for average heat transfer coefficient ware correlated by the analysis within 15%