Unstructured PEBI-grids Adapting to Geological Features in Subsurface Reservoirs

Abstract

Extensive research has been done on the generation of unstructured grids in reservoir simulation, with the aim of better representing the geology. We introduce UPR (Unstructured PEBI-grids for Reservoirs), a free, open source module for the Matlab Reservoir Simulation Toolbox. This module automates the generation of grids that conform to structures in subsurface reservoirs. The module implements the new methods presented in this thesis. These methods generate PEBI-grids that conform to wells and faults. The grids honor faults exactly. By using our novel method for treating intersections, it handles several hard cases robustly, including, intersection of multiple faults, intersections of wells and faults, and faults intersecting at sharp angles. We have also generalized our method to three dimensions, and present how one can create unstructured 3D PEBI-grids that conform exactly to faults.