Evaluation of Particle Size Distribution Models in STAR-CCM+ and OpenFOAM for Dispersed Two-Phase Flows

Abstract

The Eulerian-Eulerian framework used in Multiphase Computational Fluid Dynamics (M-CFD) is becoming an increasingly valuable tool for the design and analysis of advanced Light Water Reactors and many other applications. To produce valuable results, the Eulerian framework requires a proper model for the total interfacial area available for mass, momentum, and energy transfer between the two phases. Particle Size Distribution (PSD) models are important to incorporate within this framework to properly characterize the distribution of the dispersed phase in two-phase flows. Within the field of M-CFD, various codes exist such as the commercial software STAR-CCM+ and the open-source software OpenFOAM. Likewise, various PSD models are available within each software thanks to the ability to introduce new models, specifically in open-source codes. The method of moments is a popular PSD modeling approach, with each variation taking different approaches and making different assumptions as to the shape of the distributions, leading to a lack of consensus on their applicability. To address this issue, a set of baseline closures was chosen to evaluate the performance of the various PSD models when applied to the TOPFLOW experimental database. Breakup and coalescence models of different complexities were also tested to assess their applicability and accuracy to different flow regimes. Satisfactory agreement was obtained with certain breakup and coalescence models with the S-Gamma PSD model in STAR-CCM+ while most models within OpenFOAM obtained good agreement when using the LogMoM PSD model.