Lattice Boltzmann pseudopotential multiphase modeling of transcritical CO₂ flow using a crossover formulation

This report summarizes our recent implementation of a crossover formulation in the lattice Boltzmann method and its application in modeling transcritical CO₂ sequestration in water-saturated porous media. A crossover enhancement of the Peng-Robinson equation of state increases the accuracy in predicting fluid properties in transcritical conditions, which is relevant in modeling CO₂ sequestration. The crossover formulation leads to the prediction of liquid-vapor coexistence curves closer to experimental data. The formulation was validated with several tests and applied to model the displacement of H₂ O with CO₂ in a homogeneous porous medium in multiple conditions. This investigation provides a promising strategy for improving the accuracy of the lattice Boltzmann method in modeling transcritical CO₂ sequestration in aquifers using realistic transcritical conditions.