Flow morphology and heat transfer analysis for high-pressure steam condensation in an inclined tube part II: Numerical investigations

Abstract

In this part of the paper, we introduce and discuss the numerical investigation of two-phase flow and heat transfer during steam condensation inside an inclined tube. For that we developed and employed a three-dimensional two-phase computational fluid dynamics model in ANSYS CFX which comprises wall condensation and direct contact condensation. Wall condensation is covered by a new subgrid model for the thin liquid film. For modelling of the heat transfer on the steam-liquid interface, three different heat transfer correlations have been implemented to check their performance. Simulation results were compared with experimental data of the COSMEA facility, which has been documented in part I of this paper. Particular focus was given to the development of the liquid film inside the tube and its effects on the wall heat transfer. Moreover, we compared the CFD simulations with system code simulations performed with the ATHLET submodule of AC2.