Intermittency effects in single- and multi-phase flows in porous media

Multi-phase flow and transport in porous media is prevalent in a wide range of challenging fluid mechanics problems in sustainability, energy, and the environment. Accurate prediction and understanding of the underlying flow physics is vital in addressing these problems, particularly the small- or pore-scale study of the flow's spatial and temporal evolution, which can impact flow behavior at system scales in a nontrivial manner. Intermittency is a phenomenon observable at the pore scale in both numerical and experimental studies of single-phase flow, but the case of multi-phase flow more commonly found in natural systems has yet to receive much attention due to the challenges faced in both simulations and experiments. We present results from a computational and experimental study of intermittent behavior over a range of flow regimes in single- and multi-phase flows in 2D homogeneous and heterogeneous micromodels. Lagrangian flow statistics are obtained by Lattice Boltzmann simulations and particle tracking velocimetry (PTV) measurements to draw comparisons between computational and experimental results. The results make note of the applicability of different modeling frameworks such as the correlated-continuous time random walk.