Evaporation of refrigerant 113 flowing inside smooth tubes

Heat transfer coefficients were experimentally measured for R-113 evaporating inside uniformly heated smooth tubes and then compared with six different correlations from the literature. Experiments were performed on 4-m lengths of two different size tubes: an 8.71-mm-I.D. and a 10.92-mm-I.D. The inlet state was subcooled approximately 18/sup 0/C, while the outlet state was at a quality of approximately 0.8. Local heat transfer coefficients along the test tube were obtained from wall temperatures, fluid temperatures (inferred from saturation pressures), and electrical energy input to the fluid. Data were obtained for a range of flow rates and heat fluxes. The experimental results are compared with six of the more commonly used, in-tube evaporation, heat transfer correlations available in the literature. Interestingly, these correlations produced widely differing results. In addition, the agreement with experimental data varied with the quality range in which the comparison was being performed.