The main features of compositional modeling algorithms of modern reservoir flow simulators

Abstract

Modern industrial reservoir flow simulators are integrated software products consisting of several packages. Modeling of gas injection with various compositions, or hydrocarbon recovery from gas-condensate and oil-gas-condensate reservoirs, or thermal recovery methods requires a detailed account for composition of the fluid system. In these cases, compositional (multi-component) flow simulation is used to calculate component distribution between the coexisting phases, the number and the fractions of the phases, together with the flow equations for fluid components.. For this purpose, the flow simulator solves the thermodynamic subproblem using basic methods and algorithms analogous to the fluid modeling (PVT modeling) packages. The paper describes the main principles and specific features of implementation of the compositional modeling algorithms in several modern reservoir flow simulators. Keywords: compositional modeling; multicomponent flow model; reservoir flow simulator; isothermal and non-isothermal compositional modeling.