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arXiv · 1611.04210

Critical behavior in porous media flow

Marcel Moura·Knut Jørgen Måløy·Renaud Toussaint
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Abstract

The intermittent burst dynamics during the slow drainage of a porous medium is studied experimentally. We have shown that this system satisfies a set of conditions known to be true for critical systems, such as intermittent activity with bursts extending over several time and length scales, self-similar macroscopic fractal structure and $1/f^\alpha$ power spectrum. Additionally, we have verified a theoretically predicted scaling for the burst size distribution, previously assessed via numerical simulations. The observation of $1/f^\alpha$ power spectra is new for porous media flows and, for specific boundary conditions, we notice the occurrence of a transition from $1/f$ to $1/f^2$ scaling. An analytically integrable mathematical framework was employed to explain this behavior.

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Marcel Moura, Knut Jørgen Måløy, Renaud Toussaint. 2016-11-13. Critical behavior in porous media flow. https://doi.org/10.1209/0295-5075/118/14004

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