In-situ capillary pressure and wettability in natural porous media: Multi-scale experimentation and automated characterization using X-ray images

Carbonated Water Injection in Oil-Wet Carbonate Rock Samples: A Pore-Scale Experimental Investigation of the Effect of Brine Composition

“…First, the oil–brine interface was extracted from the segmented image containing the oil and brine labels. Extraction was implemented by a marching cubes algorithm that generates a polygonal mesh of the interface. , Thereafter, the surface mesh was optimally smoothed (10 iterations) by implementing an implicit fairing algorithm. , The magnitude and directions of the principal curvatures at each vertex were then estimated from the eigenvalues and eigenvectors of the curvature tensor. , The total curvatures were calculated as the sum of the two principal curvatures at each vertex. Finally, a representative average curvature value for the entire interface was then calculated using arithmetic averaging of the per-vertex total curvatures and substituted in the Young–Laplace equation to estimate the capillary pressure in the three-dimensional volume of interest.…”

“…We have implemented a curvature and capillary pressure analysis to further evaluate the impressive performance of the CLSSW flood. The methodology for this analysis is elaborately described in the work by Zankoor and co-workers; 54 hence, only a short description is given here. First, the oil−brine interface was extracted from the segmented image containing the oil and brine labels.…”

“…Extraction was implemented by a marching cubes algorithm that generates a polygonal mesh of the interface. 54,107 Thereafter, the surface mesh was optimally smoothed (10 iterations) by implementing an implicit fairing algorithm. 108,109 The magnitude and directions of the principal curvatures at each vertex were then estimated from the eigenvalues and eigenvectors of the curvature tensor.…”

“…108,109 The magnitude and directions of the principal curvatures at each vertex were then estimated from the eigenvalues and eigenvectors of the curvature tensor. 54,110 The total curvatures were calculated as the sum of the two principal curvatures at each vertex. Finally, a representative average curvature value for the entire interface was then calculated using arithmetic averaging of the per-vertex total curvatures and substituted in the Young−Laplace equation to estimate the capillary pressure in the three-dimensional volume of interest.…”

“…Wettability was characterized using in situ contact angles measured at the three-phase (oil, brine, and rock) contact points within selected pore elements captured on high-resolution X-ray images. Interfacial curvature and capillary pressure determination were based on the work by Zankoor et al 54…”