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arXiv · 2001.04332

Onsager-Symmetry Obeyed in Athermal Mesoscopic Systems: Two-Phase Flow in Porous Media

Mathias Winkler·Magnus Aa. Gjennestad·Dick Bedeaux·Signe Kjelstrup·Raffaela Cabriolu·Alex Hansen
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Abstract

We compute the fluid flow time-correlation functions of incompressible, immiscible two-phase flow in porous media using a 2D network model. Given a properly chosen representative elementary volume, the flow rate distributions are Gaussian and the integrals of time correlation functions of the flows are found to converge to a finite value. The integrated cross-correlations become symmetric, obeying Onsager's reciprocal relations. These findings support the proposal of a non-equilibrium thermodynamic description for two-phase flow in porous media.

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Mathias Winkler, Magnus Aa. Gjennestad, Dick Bedeaux, Signe Kjelstrup, Raffaela Cabriolu, Alex Hansen. 2020-01-13. Onsager-Symmetry Obeyed in Athermal Mesoscopic Systems: Two-Phase Flow in Porous Media. https://arxiv.org/abs/2001.04332

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