Stochastic simulation of the motion, breakup and stranding of oil ganglia in water‐wet granular porous media during immiscible displacement

The problem of immiscible displacement of oil ganglia arises in connection with oil bank formation and attrition during enhanced oil recovery with flooding. A stochastic simulation method is developed here, which enables prediction of the fate of solitary ganglia during immiscible displacement in water‐wet unconsolidated granular porous media. This method takes into account the local topology of the porous medium; the initial size, shape and orientation of the oil ganglion and the capillary number. For each ganglion size, hundreds of realizations are performed with random ganglion shapes for a 100 × 200 sandpack. These results are averaged to obtain probabilities of mobilization, breakup and stranding as functions of capillary number and ganglion size. Axial and lateral dispersion coefficients are obtained as functions of the average ganglion velocity. The results from the solitary ganglion analysis can be used with the ganglion population balance equations developed in a companion publication (Payatakes, Ng and Flumerfelt, 1980) to study the dynamics of oil bank formation.