Fully implicit method for simulation of flows with interfaces

Abstract

This paper is concerned with simulation of flows with interface between two incompressible and immiscible fluids on a fixed grid using what is called the single fluid formalism. This formalism views flow of two fluids as that of a single fluid whose density and viscosity change abruptly at the interface. The location of the interface is apriori not known but is to be discovered as part of the solution. Problems of these types are typically solved using two main approaches: a) Interface Capturing and b) Interface Tracking. The present contribution is of a former variety. The governing Navier-Stokes equations in primitive variables are solved on collocated grids with a specially derived smoothing pressure correction that satisfies volume conservation whereas superficial density is determined from mass conservation equation. It is shown that the latter equation can be cast in the form of a well known volume fraction equation. The convective terms are represented by a TVD scheme. The overall methodology is tested against few problems for which experimental data and/or numerical predictions are available.