A finite-volume/front-tracking method for computations of multiphase flows in complex geometries

Abstract

ABSTRACT* A finite- volume/front- tracking (FV/FT) method is developed for computations of mul tiphase flows in complex geometries. The method is based on the one field formulation of the flow equations and treating different phases as a single fluid with variable material properties. The FV method is based on the concept of dual time stepping and is combined with the front-tracking methodology. An alternating direction implicit scheme is used to integrate the flow equations in pseudo time and several convergence acceleration techniques such as preconditioning, local time-stepping and multigrid methods are used to accelerate the convergence of the sub-iterations in the FV algorithm. The interface is represented by connected Lagrangian marker points. A novel tracking algorithm is developed to track the position of front marker points in curvilinear grids and is found to be very robust and computationally efficient. The method is implemented to solve two-dimensional (plane or axisymmetric) dispersed multiphase flows and is validated for a vibrating drop problem, buoyancy-driven falling drops in a in a straight tube and the motion of buoyancy-driven drops in a periodically constricted tube. Keywords: A finite-volume/front-tracking method, Dual time-stepping, Dispersed mul tiphase flows, Complex geometries Submitted to Journal of Computational Physics IV