The scaling exponent of residual nonwetting phase cluster size distributions in porous media

摘要: During an imbibition process in two-phase subsurface flow the imbibing phase can displace non-wetting up to endpoint at which a residual saturation is reached (which cannot be reduced further by additional wetting due complex pore network of rock and associated strong capillary forces trap phase). The split into many disconnected clusters different sizes. This size distribution key importance, for instance context hydrocarbon recovery, contaminant transport or CO2 geo-storage; it well established that this follows power-law. However, there significant uncertainty with exact value exponent τ, mathematically describes distribution. To reduce better constrain we analysed representative experimental dataset rigorous methods, demonstrate τ substantially smaller (≈1.1) than previously suggested. raises increasing doubt simple percolation models accurately predict fluid behavior; has serious consequences processes: recovery easier predicted, but geo-storage dissolution trapping capacities are significantly potential re-mobilisation more likely believed.