Mesh Generation for Modeling and Simulation of Carbon Sequestration Process.

Recently, randomly close-packed Voronoi meshes have been proposed for simulating pervasive fracture processes in materials and structures by allowing fractures to grow only at the interelement faces of the polyhedral cells. The polyhedral cells are formulated as finite elements. A new meshing tool is presented here for creating randomly close-packed Voronoi meshes in nonconvex domains with internal surfaces. Applications using these meshes include blast and impact response of engineered structures as well as hydraulic fracturing in geostructures and the design of CO2 sequestration processes to maintain the integrity of a reservoir caprock that contains preexisting fractures and joints. Our meshing approach is based on creating a random cloud of n points whose locations are determined by solving a maximal Poisson-disk sampling problem over nonconvex domains with internal surfaces, required points, and multiple regions in contact. A novel constrained Delaunay algorithm is then utilized to generate Poisson-disk triangulations using O(n) time and memory. The required Voronoi mesh is constructed by retrieving the dual of the triangular mesh. Each phase (sampling, triangulation, Voronoi meshing) of our algorithm utilizes local operations th facilitate parallel implementations. An example of the use of this meshing tool for a fracture simulation is given.