Research Council - backup mandate Bram Huygens: Understanding and Suppressing Axial Dispersion in porous media

The axial mixing or dispersion in flows through porous media is an important problem for many technological applications, ranging from oil recovery to chemical reactors. However, and despite the advanced mathematical techniques that have already been applied to the problem, a definitive theory describing the link between the geometrical descriptors of the porous medium and the ensuing axial dispersion is still lacking. Focusing on laminar flow systems, the present project aims at resolving two important shortcomings in the existing theories, as these do not account for i) the occurrence of long-distance preferential flow paths, ii) the memory effect when species flow from one dispersion zone to another. For this purpose, so-called checkerboard media are proposed as a new means to study and model axial dispersion. These are idealized
models wherein the porous media are represented by a (regular) patchwork of different permeability zones. Dispersion measurements on 2D and 3D variants of these novel media will be made in silico via Computational Fluid Dynamics, as well as via microscopic video-recordings on microfluidic 2D-flow models. The insights from these observations will be used to adapt and extend the existing analytical dispersion models. Subsequently, the validity of the developed models will be applied to real chromatographic and geological media, as well as to a new type of pillar-reinforced monolithic packing that will be developed within the frame of the project.