An extension of the multiple marker algorithm for study of phase separation problems at the mesoscale

Overview

This technical paper extends the multiple marker algorithm to improve the numerical study of phase separation phenomena at the meso-scale. The work focuses on dispersed multiphase systems, addressing challenges related to interface tracking and phase interaction.

The proposed formulation enhances the robustness and applicability of the method for complex multiphase flow problems relevant to engineering and industrial processes.

Abstract

Multiphase fluid flow is an active field of research in numerous branches of science and technology. An interesting subset of multiphase flow problems involves the dispersion of one phase into another in the form of many small bubbles or droplets, and their subsequent separation back into bulk phases after this has occurred. Phase dispersion may be a desirable eect, for example in the production of emulsions of otherwise immiscible liquids or to increase interfacial surface area for chemical reactions, or an undesirable one, for example in the intermixing of waste and product phases during processing or the generation of foams preventing gas-liquid decoupling.

The present paper describes a computational fluid dynamics method based on the multiple marker front-capturing algorithm – itself an extension of the volume-of-fluids method for multiphase flow – which is capable of scaling to mesoscale systems involving thousands of droplets or bubbles. The method includes sub-grid models for solution of the Reynolds equation to account for thin film dynamics and rupture.

The method is demonstrated with an implementation in the OpenFOAM computational mechanics framework. Comparisons against empirical data are presented, together with a performance benchmarking study and example applications.

What This Paper Covers

• Extension of the multiple marker algorithm
• Numerical modelling of phase separation phenomena
• Meso-scale multiphase flow analysis
• Interface tracking and phase interaction
• Application to dispersed phase systems