A New Approach to Sub-grid Surface Tension for LES of Two-phase Flows

TL;DR

This paper introduces a novel sub-grid surface tension model for LES of two-phase flows, addressing previously neglected interface terms and demonstrating improved accuracy through DNS comparisons.

Contribution

It proposes the first model for sub-grid interface terms in LES of two-phase flows, using deconvolution and interface advection techniques.

Findings

Model accurately predicts interface behavior in LES.

Improved agreement with DNS results.

Addresses a gap in two-phase flow modeling.

Abstract

In two-phase flow, the presence of inter-phasal surface - the interface - causes additional terms to appear in LES formulation. Those terms were ignored in contemporary works, for the lack of model and because the authors expected them to be of negligible influence. However, it has been recently shown by a priori DNS simulations that the negligibility assumption can be challenged. In the present work, a model for one of the sub-grid two-phase specific terms is proposed, using deconvolution of the velocity field and advection of the interface using that field. Using the model, the term can be included into LES. A brief presentation of the model is followed by numerical tests that assess the model's performance by comparison with a priori DNS results