A COMPONENT-BASED EULERIAN-LAGRANGIAN FORMULATION FOR MULTICOMPONENT MULTIPHASE COMPOSITIONAL FLOW AND TRANSPORT IN POROUS MEDIA

We derive a Eulerian-Lagrangian formulation for multicomponent multiphase compositional flow and transport in porous media, by utilizing momentum balance to define a barycentric component velocity for each component based on phase velocities and the relative presence of the component in each phase. This weighted velocity obviates the need for tracking multiple phases without losing the ability to handle the nonlinear complexity of the problem. The formulation can be combined with different types of pressure solvers in solving the coupled systems of compositional models. A full thermodynamic flash calculation is carried out to determine phase stability and composition. Numerical experiments are presented to investigate the performance of the method, compared with widely used explicit and implicit upwind methods in the context of a two-phase, three component compositional flow and transport process. These results demonstrate that the Eulerian-Lagrangian formulation not only represents the solutions properly, but also has obvious computational benefits compared to the widely used traditional explicit and implicit upwind methods.