Pore-scale modelling of immiscible displacement of ScCO2-brine in a homogeneous porous network using direct numerical method

In this work, the pore-scale dynamics of immiscible displacement of ScCO2-brine in a homogeneous pore network is studied using the volume of fluid method. The simulation results are verified with the theoretical equation and literature experimental data. First, the pore-space filling is performed in a unit pore cell having an equal and unequal pore throat for both drainage and spontaneous imbibition. It is observed that the pore-space filling sequence for drainage follows the rules described by the Young-Laplace equation whereas the filling sequence did not follow the rule for spontaneous imbibition. Secondly, the simulation is performed for a homogeneous pore network. It is found that the transverse average volume fraction of ScCO2 from the simulation matches with the experimental data for intermediate and higher capillary numbers. Further, the present simulation is extended to study the flow regime identification and viscosity ratio and contact angle effects on ScCO2 volume fraction profile.