A Decoupled Approach to the Simulation of Flow and Transport of Non-Aqueous Organic Phase Contaminants Through Porous Media

Publisher Summary This chapter describes a decoupled approach to the simulation of flow and transport of non-aqueous organic phase contaminants through porous media. The introduction and migration of slightly miscible non-aqueous organic fluids in the subsurface is an environmental problem that is receiving increasing attention. In the past several years, methods initially developed to model other types of multiphase flows in porous media (flow in petroleum reservoirs, for example) have been applied to this multiphase pollution problem. Several models have been presented in the literature, which investigates immiscible fluid flow. A decoupled modeling approach to the multiphase pollution problem is presented. This approach is similar in concept to that employed to model advanced oil recovery in the petroleum engineering literature. In order to fully describe the transport problem, the mass fractions for a species in each phase must be related. This model uses the familiar local equilibrium assumption to relate the mass fractions. The increased flexibility makes the decoupled technique desirable, and the smaller matrix equations resulting from this formulation lead to a more efficient numerical model.