High-speed micro-PIV measurements of multiphase flow of water and supercritical CO₂ in a 2D circular porous micromodel

Multiphase flow in porous media is relevant to a range of applications in the energy and environmental sectors such as oil recovery. Recently, the interest has been renewed by geological storage of CO₂ within saline aquifers. While it is critical to predict the fidelity of candidate sites pre-injection of CO₂ and its post-injection migration, it is increasingly recognized that those macroscopic flow behaviors are largely controlled by pore-scale physics down to the micrometer scale. Moreover, recent evidence shows that transient flow events such as Haines jumps, occur on the time scale of milliseconds, and the dynamic effects, e.g. inertia, can greatly affect the accuracy of prediction if not accounted for properly in predictive models. To this end, the pore-scale flow of water and CO₂ is quantified using high-speed micro-PIV in a 2D heterogeneous micromodel under reservoir-relevant conditions. The high resolutions both in time and space allow us to achieve temporally- and spatially-resolved data, which is indispensable to advance our understanding of the pore-scale flow dynamics. In addition, both drainage and imbibition cases are investigated through effective alteration of the porous media wettability.