Simulating anomalous dispersion in porous media using the unstructured lattice Boltzmann method

Abstract

Flow in porous media is a significant challenge to many computational fluid dynamics methods because of the complex boundaries separating pore fluid and host medium. However, the rapid development of the lattice Boltzmann methods and experimental imaging techniques now allow us to efficiently and robustly simulate flows in the pore space of porous rocks. Here we study the flow and dispersion in the pore space of limestone samples using the unstructured, characteristic based off-lattice Boltzmann method. We use the method to investigate the anomalous dispersion of particles in the pore space. We further show that the complex pore network limits the effectivity by which pollutants in the pore space can be removed by continuous flushing. In the smallest pores, diffusive transport dominates over advective transport and therefore cycles of flushing and no flushing, respectively, might be a more efficient strategy for pollutant removal.

Evaluation of the finite element lattice Boltzmann method for binary fluid flows

“…The validity and grid convergence is This work establishes a promising venue for simulations of multiphase flows in non-trivial geometries such as real porous media, e.g., by invoking the boundary treatment developed in [18,25].…”

Phenomenological Model of Nonlinear Dynamics and Deterministic Chaotic Gas Migration in Bentonite: Experimental Evidence and Diagnostic Parameters

“…Cushman and O'Malley (2015) stated that "…the occurrence of Fickian dispersion in geophysical settings is a rare event and consequently should be labeled as anomalous." Misztal et al (2015) simulated anomalous dispersion in porous media using the unstructured lattice Boltzmann method. Ruspini et al (2014) reported the results of experiments demonstrating two-phase flow instabilities.…”

Intermittent Dynamics of Slow Drainage Experiments in Porous Media: Characterization Under Different Boundary Conditions

“…Scientists have studied the morphology and dynamics of porous media flows and proposed a set of numerical schemes able to reproduce the observed macroscopic patterns [2,3,5,7,10,[45][46][47][48][49][50][51][52] and relevant pore-scale mechanisms [6,9,26,27,47,[53][54][55]. These studies have led to a deeper understanding of the pore-scale forces that are ultimately responsible for the macroscopic flow properties and finally to the possible upscaling of the results [6,8,48].…”