Pore Scale Simulation of Two-Phase Fluid Flow in Berea Sandstone Core Using Lattice Boltzmann Method

Study of flow through porous media has been an area of major interest due to its application in diverse areas like Enhanced Oil Recovery. In order to gain a better understanding of the physical processes taking place inside a porous structure, a large number of attempts have been made to computationally simulate multiphase fluid flow at pore-scale. Recently, application of Lattice Boltzmann Method has gained popularity for this very purpose, considering its relative superiority in dealing with complex boundaries and multiphase flow. However, in order that such a numerical analysis is successful, a proper understanding of the geometry of the pore structure at the microscale is required. This paper uses a Micro-CT scan image of a Berea Sandstone core, which displays a two dimensional representation of pore network inside the scanned sample. The processed image has been imported and simulation of an immiscible two-phase flow has been carried out by using a Lattice Boltzmann program. The resident fluid (oil) has been displaced by the invading fluid (water) due to application of a pressure gradient. The pore surfaces have been treated as solid boundaries and bounce back scheme has been implemented on them to account for the no-slip condition. The ability of the code to import an arbitrary porous geometry and perform numerical analysis of fluid flow has been demonstrated.