Characterisation of fluid flow through porous media using three-dimensional microimaging and pulsed gradient stimulated echo NMR

Pulsed gradient stimulated echo (PGSTE) and microimaging nuclear magnetic resonance (NMR) are used to probe correlations between structure and flow in the void space of a model porous system formed from a packing of 1-mm diameter glass spheres. The pulsed gradient stimulated echo data determine the average propagator and permit the dispersion of the flow to be studied as a function of delay time. Microimaging yields structural information and, specifically, a reduced radial distribution function (rdf) for the structure of the void space. Transition to fully developed dispersive flow is shown to occur on a scale size for which no further correlations in the structure of the void space are observed.