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Title: Temporal Evolution of Erosion in Pore Networks: From Homogenization to Instability
We study the dynamics of ow-networks in porous media using a pore-network model. First, we consider a class of erosion dynamics assuming a constitutive law depending on ow rate, local velocities, or shear stress at the walls. We show that depending on the erosion law, the ow may become uniform and homogenized or become unstable and develop channels. By de ning an order parameter capturing these di erent behaviors we show that a phase transition occurs depending on the erosion dynamics. Using a simple model, we identify quantitative criteria to distinguish these regimes and correctly predict the fate of the network, and discuss the experimental relevance of our results.  more » « less
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Physical Review Letters
Medium: X
Sponsoring Org:
National Science Foundation
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