Numerical simulation of species transfer across fluid interfaces in free-surface flows using OpenFOAM

This paper presents the Continuous-Species-Transfer (CST) method, which enables interface capturing techniques – a group among Computational Multi-Fluid Dynamics (CMFD) methods that rely upon a smooth interface representation – to deal with species transfer. In this study we examine realistic species transfer across fluid interfaces, taking into account both the steep interfacial concentration gradients (at high Schmidt numbers) and the sharp interfacial concentration jump (at high Henry coefficients due to different species solubilities). Thus, the main objective is to establish the CST method for species transfer across fluid interfaces of arbitrary morphology in free-surface flows at high viscosity and density ratios.Detailed numerical simulations of single rising bubbles have been performed at high resolutions. Results were compared to experimental data and correlations derived thereof.

► Novel method – Continuous-Species-Transfer (CST) method. ► Set of governing equations consistent and valid throughout domain. ► Validation results in very good agreement with both detailed models and experiments. ► Applicability to realistic systems.