CO2 FLOW PATTERNS UNDER MULTIPHASE FLOW - HETEROGENEOUS FIELD-SCALE CONDITIONS

A finite-difference, equation-of-state (EOS), compositional simulator has been used to study CO:! flooding. First, unstable first-contact-mi scible (FCM) displacements were simulated with a fine mesh to investig ate the transition from gravity override to viscous fingering. Next, a direct comparison was made for FCM and multiple-contact-miscible (MCM ) displacements under the same conditions to investigate effects of ph ase behavior on the growth of viscous fingers. Then, the effects of gr avity, physical dispersion, capillary pressure, phase behavior, and he terogeneity were combined and simulated for CO2 flooding on a field sc ale with stochastic permeability fields.