Coupling of volume of fluid and level set methods in condensing heat transfer simulations

Abstract

Additive Manufacturing (AM) is a rapidly developing new technology which allows the manufacture of arbitrarily complex geometries, and which is likely to transform heat exchanger design. To drive this transformation we need to develop computer modelling techniques to model fluid flow, heat exchange and phase change in arbitrarily complex domains, such as can be manufactured using AM. The present work aims to develop a computational fluid dynamics (CFD) model for heat transfer and phase change, robust enough to model compact AM heat exchangers for automotive fuel cell application. The hydrodynamics of the two-phase flow is captured via the Volume Of Fluid (VOF) approach, coupled with a Level Set method in order to capture the sharp interface between liquid and vapour in laminar film condensation. The Stefan problem is used to show the improvement of the interface tracking with LS-VOF against VOF approach. The resulting complete condensation model is applied for the first time for a complex AM geometry and validated against experimental data.