Experimental investigation of the mutual influence of micro- and macroscale processes on the displacement of viscous oil by water in a two-layer porous medium

Abstract

This paper presents the results of an experimental and theoretical study of the immissible displacement of high-viscosity model oil from the two-layer porous medium with different layers permeability. The experiments were performed using cylindrical model of the porous medium having the ratio of transverse size to length D/L equals to 0.05 and ratio of layers permeability equals to 0.46 during forced imbibition and drainage. It is shown that the alignment of a displacement front in the layers is caused by macroscale capillarity-driven flow arising from the curvature of the front. The conditions for stabilized motion of the displacement front for this case are determined using the analytical model and proved using experimental data on the recovery of displaced fluid. Microscale processes in pore level caused by the influence of the capillary forces are taken into account throw the relative phase permeability and capillary pressure curves.