Abstract
Distribution of supercritical CO_2 injected into a packed bed of glass beads containing water is visualized directly by utilizing an MRI technique. After the CO_2 displaced much of the water, some water remained near the central axis, although there were several mm-sized, CO_2-rich channels running through this water-rich region. To better understand the results, we also used the lattice Boltzmann method (LBM), to numerically simulate this system. In a parallel channel with hydrophilic surfaces, a high velocity of water between the bubbles along the flow direction results in a high relative permeability at low water saturations. The effect of capillary contraction along the flow direction was also simulated. The flow through a narrow channel consisted of water and periodic passages of a CO_2 bubble. Channels with smaller cross-sectional areas have faster flow speeds, especially for a CO_2 bubble.
