Numerical Simulation of Multiphase and Multicomponent Fluid Flow in Petroleum Reservoirs Using a Fully Implicit Formulation

Resumo

Of the many techniques and tools used for estimating oil and gas production in the recovery processes,
compositional simulation model is important for problems with complex phase behavior, as in the application of
Enhanced Oil Recovery (EOR) methods. The solution of the compositional model involves spatial and time
discretization schemes and approaches for handling the coupling of fluid flow and phase behavior. Several solution
algorithms arise from combining the different selection of primary variables and decoupling techniques. In this
work, we present a Fully Implicit (FI) formulation using cartesian grids for the compositional reservoir simulation
based on Equation of State. For the diffusive terms of the equations that describe the mathematical model, we
discretize by the Two-Point Flux Approximation (TPFA) finite volume method, while in the advective terms, we

apply the first-order upstream weighting. So far, the implemented model considers isothermal flow, up to three-
phase flow, and that there is no mass transfer between water and hydrocarbon phases. Physical dispersion and

capillary pressure effects are neglected. Our FI formulation is evaluated by solving a benchmark problem found
in literature and the results are promising, providing a basis for future implementation of a non-isothermal model
to simulate EOR problems, such as steam injection.