Topological changes due to non-equilibrium effects by means of the statistical model of two-phase flow

TL;DR

This paper introduces a statistical model for two-phase flow that captures non-equilibrium effects in the intermittency region, revealing topological changes in flow structures not seen in traditional models.

Contribution

It presents the first application of a statistical approach to two-phase flow simulation, highlighting differences from deterministic models and potential to include previously neglected physical phenomena.

Findings

Differences between equilibrium and non-equilibrium solutions are demonstrated.

Statistical description captures non-equilibrium effects in the intermittency region.

Potential to improve two-phase flow simulations by accounting for additional physical phenomena.

Abstract

This paper presents the first results of the two-phase flow simulation obtained using recently introduced physical, mathematical and numerical model of the intermittency region between two-phases (Wac{\l}awczyk 2017, 2021). The statistical interpretation of the intermittency region evolution equations allows to account for the non-equilibrium effects in the domain separating two phases. The source of non-equilibrium are spatial variations in the ratio of work done by volume and interfacial forces governing its width. As the statistical description of the two-phase flow differs from the deterministic two-phase flow models known in the literature, in the present work we focus discussion of the results on these differences. To this goal, the rising two dimensional gas bubble is studied; differences between equilibrium and non-equilibrium solutions are investigated. It is argued the statistical description of the intermittency region has potential to account for physical phenomena not considered previously in the computer simulations of two-phase flow.