Dynamic permeability reduction and scaling of flow in porous media

Precipitation of minerals, adsorption of nanoparticles and trapping of immiscible fluids in porous media result in changes in the available flow paths and modify the permeability of the medium. We use confocal microscopy and bulk transport measurements to probe the local flow and permeability of the medium in 3D porous micromodels. Our experimental measurements show that depending on the time allowed for changes in the structure and response from the flow, the structure of the medium self-regulates. Nevertheless, the probability distribution of fluid velocities retain the same shape. We find that at a constant volumetric flow rate, the self-regulated media have an intrinsic length-scale that can be estimated from the bulk permeability of the medium.