Numerical modeling of fluid flow during geologic carbon storage

In this chapter we discuss the different numerical modeling tools available for simulation of fluid flow induced by geologic carbon storage (GCS) operations. The governing equations of multiphase flow are introduced and common solution approaches are discussed for different spatial scales (e.g., basin-wide pressure perturbation, flow along concentrated leakage pathways). The main focus of this chapter is on three-dimensional and vertically integrated approaches. In three-dimensional approaches, the governing equations are discretized in the three spatial dimensions for numerical solution, while for vertically integrated approaches the governing equations are integrated over the thickness of a formation and the resulting two-dimensional system is solved numerically. Recent developments relating to vertically integrated approaches-such as inclusion of vertical dynamics-are also presented. We also discuss the applicability of different GCS modeling approaches to three different spatial scales: well-scale, site-scale, and basin-scale.