Microtomography of multiphase flows in porous media
Multiphase flow in porous media occurs in many practical situations including carbon dioxide capture and storage, enhanced oil recovery, remediation of polluted ground, and soil science.
However, since porous media are optically opaque, there is only a limited knowledge of phenomenological descriptions of the average fluid properties over several pores.
Recent rapid improvements in X-ray computer tomography allow us to directly visualize fluid dynamical events at the pore scale.
Now, a team of energy engineers at Tokyo Tech is devising ways to adapt a microtomography scheme to visualize multiphase flows in porous media. A new tracer scheme was developed to visualize the flow field of multiphase flow in porous media on tomograms.
When oil was produced from reservoirs, a large fraction of the oil was trapped in pores. Water invaded into the throat of pores, and snapped off the oil blobs from the continuous oil. After that, the water surrounding the trapped oil blobs became stagnant. These findings are helpful to improve oil recovery from reservoirs.
The new visualization scheme could be used to produce visual information on transport in porous media.