The quantification of trapped non-wetting phase saturation and distribution in petroleum reservoirs is essential to understand hydrocarbon recovery efficiency. Laboratory experiments on core samples are regarded industry best practice to estimate hydrocarbon trapping. To implement entrapment characteristics in reservoir modeling, empirical correlations between initial saturation and respective residual non-wetting phase saturation (trapping curves) are commonly used.

To overcome long lead times for setting up reservoir models due to time-consuming laboratory workflows, pore-scale simulations of fluid flow on digital representation of the pore space - so called digital twins - imaged by micro computed tomography have been considered a viable alternative to estimate hydrocarbon entrapment. In this study, we compare simulation results for water/gas capillary dominated imbibition in a sandstone reservoir. So far, digital rock simulations could not predict representative trapped phase saturation levels with the classical morphological approach. This was the motivation to adapt the simulation concepts by inclusion of sub-resolution wetting-phase layers to the pore-structure. As a result, it was possible to simulate representative spatial distribution of the trapped non-wetting phase in the pore-space and to estimate realistic residual saturations. For verification purposes, the simulated results have been compared to the trapping model by Land (1968) .