Voronoi Meshing to Accurately Capture Geological Structure in Subsurface Simulations

Abstract Mesh generation lies at the interface of geological modeling and reservoir simulation. Highly skewed or very small grid cells may be necessary to accurately capture geometry features, but resulting poorly scaled can have a substantial negative impact on simulator accuracy speed. One way minimize numerical errors caused by gridding complex structures is simulate high-quality Voronoi meshes, which reduce orientation effects in fluid flow. This work presents complete methodology create simulation grids, model flow systems, visualize results. A recently developed meshing method that automatically generate provably good unstructured meshes conform input surfaces creating closed volumes used. Initially an analytical benchmark presented validate quality results demonstrate superiority using over flexed-hexahedral domain with internal features. Next, are created for test representing four most common features subsurface: layering, pinch-out, interior lens tapers zero thickness all sides fault offset. Two simulations run each structure. Finally, realistic example CO $$_2$$ 2 injection into anticline simulated. Three realizations mesh same resolution generated simulations. Each highly refined near wells coarse areas less interest. These three used plume subsurface as it migrates top structure then fills downward. Simulations randomly elements inside give slightly different fingering patterns viscous-unstable buoyant gas The this show promising step towards utilizing fully automated geology.