Modeling Multiphase Flow Within and Around Deformable Porous Materials:
A Darcy-Brinkman-Biot Approach
Abstract
We present a new computational fluid dynamics approach to simulating
two-phase flow in hybrid systems containing solid-free regions and
deformable porous matrices. Our approach is based on the derivation of a
unique set of volume-averaged partial differential equations that
asymptotically approach the Navier-Stokes Volume-of-Fluid equations in
solid-free-regions and multiphase Biot Theory in porous regions. The
resulting equations extend our recently developed Darcy-Brinkman-Biot
framework to multiphase flow. Through careful consideration of
interfacial dynamics (relative permeability and capillary effects) and
extensive benchmarking, we show that the resulting model accurately
captures the strong two-way coupling that is often exhibited between
multiple fluids and deformable porous media. Thus, it can be used to
represent flow-induced material deformation (swelling, compression) and
failure (cracking, fracturing). The model’s open-source numerical
implementation, hybridBiotInterFoam, effectively marks the
extension of computational fluid mechanics into modeling multiscale
multiphase flow in deformable porous systems. The versatility of the
solver is illustrated through applications related to material failure
in poroelastic coastal barriers and surface deformation due to fluid
injection in poroplastic systems.