2020/11/27 by B. Chencarek, Marisa Nascimento, Chencarek, B. +11
Engineering · Medicine · Physics and Astronomy · #Advanced Neuroimaging Techniques and Applications #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Geophysics (physics.geo-ph) #Heat and Mass Transfer in Porous Media #NMR spectroscopy and applications #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.2011.13703
openalex publication_date 2020/11/27 · openalex created_date 2020/12/07 · openalex updated_date 2026/07/28
In this work, we present a characterization of phase configuration in water-saturated sintered glass bead samples after oil injection, through the analysis of time-dependent diffusion coefficients obtained from sets of one-dimensional pulsed field gradient nuclear magnetic resonance (PFG NMR) measurements, pre and post drainage. Estimates of samples surface-to-volume ratio and permeability from pre drainage PFG measurements in a water-saturated sample were compared with analytical and reported values, respectively, and a fair agreement was found in both cases. Short-time analysis of diffusion coefficients extracted from PFG measurements was used to quantify the increase in surface-to-volume ratio probed by the wetting phase after drainage. Analysis of water and oil diffusion coefficients from post drainage PFG experiments were carried out using a bi-Gaussian model, and two distinct scenarios were considered to describe fluids conformation within pores. For the case where non-wetting phase was considered to exhibit a poorly connected geometry, an analysis assuming the formation of oi-in-water droplets within pores was performed, and a Gaussian distribution of droplets radii was determined.