Closure proposals for the tracking of turbulence-agitated gas–liquid interfaces in stratified flows

The present work focuses on the formulation of new modelling approaches to ensemble-averaged equation for the interface tracking in stratified two-phase flow regime with separated gas and liquid layers. The model aims to represent the influence of the unresolved part of the surface. The modelling constants have been estimated based on the k–ϵ model and the empirical observations of Brocchini and Peregrine (2001a) for the air–water flows. The new modelling proposal was implemented numerically for the 1D case. Results of the simulations are presented in the paper.

► We investigate turbulent two-phase flows with the interface.
► We formulate new closure proposals for the interface tracking.
► The model accounts for the region where the pdf of the surface position is non-zero.
► Model constants are estimated based on experimental observations.
► We perform 1D numerical simulations with the new model.