Two-phase flow in a quasi-2D porous medium: investigation of boundary effects in the measurement of pressure-saturation relationships
Marcel Moura, Ph.D student in the Condensed Matter Physics group, will present his work on "Two-phase flow in a quasi-2D porous medium: investigation of boundary effects in the measurement of pressure-saturation relationships"
(top) Final stage of the experiment: air flows from right to left displacing part of the fluid in the medium and leaving some clusters of trapped fluid behind. (bottom) Close-up of a typical pore invasion event. The diameter of the beads is about 1 mm.
We have performed two-phase flow experiments to analyze the primary drainage from a quasi-2D artificial porous medium. The medium is transparent, which allows for the direct visualization of the invasion pattern during the flow. Pressure measurements and pictures of the flow are recorded and the pressure-saturation relationship is computed. This relationship is important for the closure of the partial-flow Darcy equations, frequently used in the simulations of flow in porous media. The effects of the system’s boundaries on this curve are investigated and we propose a simplified description for the pressure-saturation relationship for the regions of the system in which the boundary effects are negligible. Additionally, the use of a high-resolution camera allows us to analyze the images down to the pore scale. We can directly obtain a distribution of pore-throat sizes in the model and divide it into distributions of invaded / non-invaded pores. By measuring these separate distributions dynamically, we can show how they evolve with the invasion process.