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

• Water conductivity with SPH was similar to that experimentally measured at saturation.
• Pore morphology had only a marginal role in water flow prediction.
• The macropore network was composed of a massive singular pore within the soil core.
• The increase of scanning resolution will improve water flow prediction.

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