Journal
JOURNAL OF FLUID MECHANICS
Volume 942, Issue -, Pages -Publisher
CAMBRIDGE UNIV PRESS
DOI: 10.1017/jfm.2022.386
Keywords
porous media; microfluidics
Categories
Funding
- National Key Research and Development Program of China [2019YFA0708704]
- National Science Foundation (NSF) of China [U1837602]
Ask authors/readers for more resources
This study reports the non-monotonic wettability effects on displacement efficiency in porous structures. Experiments show that there exists a critical wettability in porous matrix structures with preferential flow pathways to achieve the highest displacement efficiency. The distribution of phases in porous structures also varies under different wettability conditions. Pore-scale mechanisms are identified to explain the formation of this non-monotonic wettability rule.
We report non-monotonic wettability effects on displacement efficiency in heterogeneous porous structures at the post-breakthrough stage, in contrast to the monotonic ones in homogeneous porous structures. Experiments on designed microfluidic chips show that there exists a critical wettability to attain the highest efficiency of displacement in the porous matrix structure combined with a preferential flow pathway, while a stronger wettability of the displacing fluid leads to a higher displacement efficiency on the same matrix structure only. The porous structure with or without a preferential flow pathway results in totally different topological characteristics of phase distribution during displacement. Pore-scale mechanisms are identified to elucidate the formation of this non-monotonic wettability rule: cooperative pore filling under weakly water-wet conditions yields the best displacement; corner flow under strongly water-wet conditions and Haines events under strongly oil-wet conditions decrease the displacement efficiency. The pore-scale findings may provide unique insights into the joint effects of both wettability and flow heterogeneity on fluid displacement in porous media.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available