CFD-XDEM FOR PREDICTING MULTIPHASE FLOW BEHAVIOR THROUGH POROUS MEDIA

An accurate description of fluid flow through porous media is very important to predict, design and optimize
many industrial phenomena principally in condition where experimental studies are difficult to perform. In
these kind of problems numerical simulations can help to gain a better process understanding. During last
decades many numerical approaches mainly Finite Volume Method (FVM) were applied to model different
multiphase flows containing gas, liquid and solid phases. The solid phase may treat by continuous or discrete
frameworks. In the former method which is based on Eulerian framework the solid phase is considered as a
continuous phase like other fluid phases while in the second method which is based on Lagrangian
framework, the solid phase is considered as separate particles.
In this study, the flow behavior of several incompressible isotherm phases through solid particles was
modelled. The model describes the motion of fluid flows such as gas and liquid phases using continuum
approach by applying Computational Fluid Dynamics (CFD) as a numerical method and the solid particles
by Lagrangian framework using so-called eXtended Discrete Element Method (XDEM). XDEM is a
numerical simulation framework based on classical Discrete Element Methods (DEM) extended by
consideration of thermophysical states. A combination of the two numerical methods was performed through
momentum and mass exchange between fluid and solid phases which is called combined continuum discrete
approach. The solid phase is considered as packed solid particles.
The model results demonstrate enormous effect of solid particles on deviation of fluid phases while passing
through particles by testing different drag force models. This model was applied to the dripping zone of blast
furnace where the liquid phases of liquid iron and slag flow downward through coke particles and gas phase
ascends upwards through the shaft which is classified as a counter-current multiphase packed bed reactor.
The main goal of this project is to provide a solver which is able to treat several fluid phases through porous
media using combined Eulerian-Lagrangian framework by exchanging data between this two approaches.