Application of smoothed particle hydrodynamics (SPH) and pore morphologic model 2 to predict saturated water conductivity from X-ray CT imaging in a silty loam Cambisol

Abstract : 20 This study aims to estimate saturated hydraulic conductivity in a silty loam soil and compare modelled data with 21 experimental ones. The flow characteristics of twelve undisturbed soil cores (5 cm in diameter × 6 cm high) were 22 measured in the laboratory after performing X-ray computed microtomography (microCT) analysis. MicroCT 3D 23 imaging was integrated with an existing pore morphologic model and a numerical simulation based on mesh-24 free smoothed particle hydrodynamics (SPH) to calculate the water flow through the macropore network 25 (pores N 40 μm). Results showed that the proposed SPH method was able to predict hydraulic conductivity of 26 large-sized samples as falling in the range of the experimental ones. By contrast the morphologic model generally 27 underestimated the water flow and was slightly affected by the pore shape. Increasing microCT imaging resolu-28 tion and expanding the variability with other soil types will improve the understanding of the role of micropore 29 size and morphology on water conductivity. 30