Modeling condensation heat transfer on a horizontal finned tube in the presence of noncondensable gases

European designs for the next generation of nuclear reactors incorporate in novative passive systems in their containments to enhance heat removal by c ondensation under postulated accident conditions. These systems consist of several units of cross-flow finned tube bundles internally cooled with wate r. So far most of the studies that have been addressed to the issue of heat transfer onto finned surfaces under condensing conditions have involved re frigerants and pure vapor conditions. This study presents a model (HTCFIN) capable of predicting condensation of a cross-flow air-steam mixture onto a single horizontal finned tube. The comparison of HTCFIN predictions to the available databases shows its acceptable accuracy in a wide range of condi tions and allows an interpretation of the influence of major variables acti ng on the scenario. As a consequence, HTCFIN model represents a step forwar d in the present theoretical capability to estimate heat transfer within co ntainments of next generation of European reactors in the case of a hypothe tical accident. (C) 2000 Elsevier Science S.A. All rights reserved.