Computational Study for the Diameter Effect on Condensation Heat Transfer on Outer Surface of a Heat Exchanger Tube

PCCS (Passive Containment Cooling System) comprised of heat exchanger tubes were devised for iPOWER (innovative Power Reactor) concept design. To guarantee the cooling performance of the PCCS, the condensation heat transfer needs to be accurately calculated. The relation between diameter of PCCS heat exchanger and condensation heat transfer coefficient has been investigated in the present study and the heat exchanger design was selected based on the JNU (Jeju National University) experiment. A curvature effect correction factor was derived by Popiel and Dehbi used the parameter when proposing his generalized condensation heat transfer coefficient correlations. In this study, the condensation phenomena simulations were performed to derive the curvature effect correction factor applicable to the condensation phenomena. Based on the CFD analysis results, Bird correction factor was selected as a parameter for condensation phenomena. The fitting equation was introduced which shows good agreement with CFD results. The modified correlation can be expected to be applicable as a curvature effect correction factor when deriving generalized condensation heat transfer coefficient correlations. For the further works, as validation of modified curvature effect correction factor, quantitative comparison between the modified curvature effect correction factor and the experimental results of curvature effect on condensation will be conducted.