Experimental Study of Non-Newtonian Behavior of Foam Flow in Highly Permeable Porous Media
Sagyn Omirbekov, Hossein Davarzani, Azita Ahmadi-Sénichault
Abstract
Foam-flow behavior in highly permeable porous media is still unclear. Two types of pregenerated foam using porous columns filled with fine sand and 1 mm glass beads were studied in different packs of glass beads with monodisperse bead size. Foam generated in fine sand had a sharp displacing front. However, the foam pregenerated using 1 mm glass beads had a transition zone front. We found that the transition foam-quality regime was independent of the porous medium grain size only when the bubbles are smaller than the pores. The apparent viscosity of foam was found to follow the Herschel–Bulkley model if the foam bubble sizes were smaller than the pore sizes. When the bubbles were of the same size as the pores, the foam behaved like a Newtonian fluid at low flow rates and, by increasing flow rates, exhibited shear-thinning fluid behavior. Furthermore, the apparent foam viscosity was found to increase with permeability.