Reproducing the microXCT observations of air-water distribution in porous media by revised pore morphology method

This study presents a novel and simple morphology approach to generate two-dimensional air-water distribution in porous media considering the cavitation mechanism (Or and Tuller 2002). The connectedness condition for the non-wetting phase is replaced by the Laplace equation. An algorithm is developed to detect the ruptured water spaces that are incorrectly formed in the throat by morphology approach but cannot exist in real thermodynamic equilibrium system. The distributions of soil moisture, water retention curve and air-liquid interface area at different saturations predicted by this method is in a good quantitative agreement with the experimental observations on glass beads and Ottawa sand from Micro X-ray Computed Tomography (microXCT). Comparing to the Monte Carlo Lattice-Gas approach (Lu et al. 2010), another computational method to generate the soil moisture distribution, the proposed approach provides better results with significantly less computational power.