A numerical study of the critical gas saturation in a porous medium

We use pore-network simulations to study the dependence of the critical gas saturation in solution-gas drive processes on the geometric parameters of the porous medium. We show that for a variety of growth regimes (including global and local percolation, instantaneous and sequential nucleation, and mass-transfer driven processes), the critical gas saturation, S-gc, follows a power-law scaling with the final nucleation fraction (fraction of sites activated), f(q). For 3-D processes, this relation reads S-gc similar to f( q)(0.16), indicating a sensitive dependence of S-gc to f(q) at very small v alues of f(q).