Pore-scale simulation of complex fluids through porous media

Flow of complex fluids through porous media is of great importance as it is the core aspect of many natural and engineering processes such as enhanced oil recovery. Although flow of Newtonian fluids at the pore-scale is well understood, pore-scale study of physical processes underpinning macroscopic flow behavior of complex fluids in porous media such as shear thickening above a critical Deborah number is lacking. In this work, using high resolution direct numerical simulations, we investigate the flow of complex fluids through random arrays of cylinders for a range of Deborah numbers and show that consistent with experimental observations, followed by a period of shear thinning at small Deborah numbers, there exists an onset of flow thickening. We show that in this regime, presence of large normal stresses in the form of filaments affect the velocity distribution and particle dispersion compared to those of Newtonian fluids.