In porous media, fluid transport typically occurs through an interconnected network of pore bodies and throats, referred to here as the primary network. During drainage, when a non-wetting phase displaces a wetting phase (e.g., air displacing water in a porous rock), thin films of the wetting phase often remain adhered to grain surfaces. Under certain conditions, these residual films can merge...
Moving contact lines in microchannels play a central role in many porous-media and microfluidic processes, yet they remain challenging to simulate accurately due to the stringent requirements on curvature and surface-tension evaluation near solid boundaries. We investigate contact-line dynamics in microchannels using direct numerical simulations within a volume-of-fluid (VOF) framework. To...
We investigate the flow of yield-stress fluid using a pore-network model, a simplified representation of porous media. Dynamic two-phase flows are considered, where a Newtonian fluid is injected into a medium initially saturated with a yield-stress fluid. In this system, yield stress competes with both capillarity and viscous forces, leading to the appearance of multiple new flow regimes.
A...
Wetting of a single pore by a liquid phase is a fundamental process in multiphase flow through porous media, and is relevant for many natural and industrial processes. While static wetting is well understood, the dynamic wetting behavior in pores still poses challenges for both experiments and numerical simulations. One major difficulty arises at the contact line, where the fluid interface...
The resistivity index (RI) is a key parameter that describes how a rock’s electrical resistivity varies with changes in fluid saturation. Electrical conduction within porous media is primarily controlled by the presence and distribution of conductive fluids such as water. When non-conductive fluids like oil or gas occupy the pore spaces, these conduction pathways are disrupted and, as water...
The deformation of fluid elements plays a central role in solute by steepening concentration gradients, increasing interfacial area for diffusive mass transfer, and enhancing encounter rates between solutes and reactive surfaces (e.g. Borgman et al. 2023, Izumoto et al. 2023, Aquino et al. 2023, Le Borgne and Heyman 2025). In three-dimensional porous media, fluid deformation at the pore scale...
Natural convection in porous materials governs heat transport across scales ranging from planetary subsurface convective systems to engineered cooling systems in micro-electronics.
While the onset of buoyancy-driven flow in such systems is well captured by linear stability analysis within a porous-continuum framework, the subsequent transition toward inertia-dominated and ultimately free...
This study investigates a velocity PDF-based stochastic model for predicting particle dispersion in flow through porous media. Modeling dispersion involves an inherent trade-off: Pore-resolved simulations provide high resolution and accuracy but require substantial computational effort, whereas reduced-order models improve efficiency at the cost of physical detail. The model investigated here...
Fluid flow and solute transport in microvascular networks plays a central role in oxygen delivery and metabolic waste clearance in the brain [1]. The distribution of blood travel times, the times needed for blood to flow from one arteriolar end to a venular end, has been identified as a key property for the extraction of oxygen by brain tissue [2]. Broad travel time distributions can...
This work, carried out within the GeoSafe consortium, combines laboratory measurements, imaging, and numerical modelling to demonstrate how pore-scale simulations can constrain upscaling parameters - particularly dispersivity - for continuum-scale reactive transport models. The Digital Rock Physics (DRP)-informed workflow, implemented in our open-source code GeoChemFoam...
A theoretical approach to estimating stable drainage front widths in three-dimensional (3D) random porous media under gravitational and capillary effects is presented. Based on the frontier of the infinite cluster in gradient percolation, we propose an expression for the 3D front width dependent on the pore-network topology, the distribution of capillary-pressure thresholds for the pore...
The water percolation threshold in porous media represents the critical saturation where fluid transitions from isolated clusters to a connected network, which is vital for transport in porous media. Traditional approaches to determine this threshold rely on laboratory experiments and empirical fitting. Percolation theory offers a theoretical foundation for locating this threshold in an ideal,...
Polymer fluids, a blend of polymers in water, provide a cost-effective and environmentally sustainable solution for supporting deep underground excavations. Their support mechanism stems from the drag force exerted at the grain scale. However, as non-Newtonian fluids, their full potential in construction applications remains untapped due to limited understanding of their behavior. In this...
When modelling fluid flow in porous media, invasion percolation is a widely employed approach to determine how two immiscible fluids distribute in the pore structure of the medium. In the invasion percolation model, an invading fluid (e.g. water) displaces the defending fluid (e.g. oil or air) when its capillary pressure exceeds the pores’ threshold capillary pressure. This approach is often...
Mineral precipitation reshapes pore geometry, connectivity, and interfacial structure, with direct consequences for diffusive and advective transport in variably saturated porous media. While it is well established that classical laws such as Kozeny-Carman and Archie’s law break down in fully saturated reactive systems, analogous saturation-based closures-such as Millington-Quirk-type...
The dynamic behavior of nucleation and precipitation of minerals in porous media during underground fluid injection has significant impact on many engineering applications such as shale gas extraction and CO₂ sequestration. Traditional large-scale models usually overlook the role that mineral nucleation plays in this reactive flow process by assuming precipitation occurs once the solution is...
Coupled dissolution and precipitation governs many geophysical processes and applications. For example, carbon mineralization is a promising strategy for long-term CO₂ sequestration that involves dissolution and precipitation. During CO₂ mineralization, dissolution of primary minerals can lead to the precipitation of secondary minerals that could clog preferential flow paths, limiting the...
Keywords: Salt precipitation, Porous media, Permeability reduction, X-ray tomography
Salt crystallization is a well-known issue during subsurface gas injection and production operations, particularly in the context of CO₂ storage in saline aquifers, where salt precipitation can significantly impair permeability and injectivity. Experimental studies have reported permeability reductions...
Mineral dendrites are an example of ramified patterns that form in rocks infiltrated by Mn-rich hydrothermal fluids. Interaction of these fluids with oxygenated environments within the rock matrix leads to the formation of manganese oxide, which subsequently precipitates and forms intricate patterns. Manganese-oxidizing bacteria are known to catalyze Mn oxidation reactions by several orders of...
Chemical gradients are ubiquitous in porous and confined environments, arising from localized solute release, dissolution, and reactive boundaries. Yet pore-scale transport models often treat colloids as passive tracers whose spreading is set by advection, diffusion, and geometric trapping. Here we show that even weak gradients can qualitatively reshape colloid dispersion through...
Preferential flow in heterogeneous porous media leads to highly uneven transport and limits the efficiency of many natural and engineering processes. Although shear-thinning polymer solutions are widely used to modify flow behavior, their rheology often amplifies flow heterogeneity under strong permeability contrasts. Here we show that shear-thinning suspensions of cross-linked polymer...
Particle transport and retention in porous media are governed by a complex interplay between fluid dynamics, particle properties, and pore geometry, leading to inherently stochastic clogging behaviors. In particular, hydrodynamic particle bridging---where suspended particles form stable arches that block pore constrictions---remains poorly captured by conventional pore-network models. In this...
Salt precipitation during CO₂ injection into saline reservoirs is widely recognized as a critical challenge for maintaining injectivity and ensuring long-term storage security. Precipitation-induced pore blockage can significantly impair multiphase flow, yet the pore-scale mechanisms governing salt formation, growth, and spatial distribution during brine-CO₂ displacement remain poorly...
The numerical characterisation of microstructures is of paramount interest in a wide range of applications, such as battery manufacturing, which relates to porous materials. Extracting reliable and relevant features that accurately describe the multi-scale morphology of materials is a delicate task. Tortuosity [1], a multifaceted concept, is one of the key structural characteristics of...
Conventional pore-scale approaches face a trade-off between accuracy and computational efficiency. While direct numerical simulation (DNS) explicitly resolves fluid-solid interfaces, it typically requires boundary-conforming meshes, limiting its applicability to complex geometries and large image-based rock samples. Single-domain micro-continuum models based on the Darcy-Brinkman-Stokes (DBS)...
Dissolution of solid mineral in porous media due to the introduction of reactive fluids is of utmost importance for a wide range of subsurface applications, including CO2 storage, geothermal systems, hydrogen technology, and enhanced oil recovery. The conditions of the injection process as well as the mineral properties strongly influence the resulting dissolution pattern, leading to compact,...
Technical textiles can be described as complex porous media whose performance is governed by coupled air, moisture and heat transport mechanisms across multiple length scales. These transport properties play a critical role in determining thermal comfort, functional efficiency and, in specific applications, user safety. However, their experimental characterisation remains challenging due to...
The movement of multiple fluids through porous media is commonly described through phenomenological extension of Darcy's law for single phase flow, assuming the different fluids follow distinct and stable pathways. However, experimental studies have shown that this is frequently violated: fluids can undergo intermittent rearrangements. These rapid events promote phase fragmentation and can...
In this work we introduce a new pore-scale model for investigating particulate transport in porous media. This model is able to capture particle-particle interactions that has a big impact on the particulate motion in dense suspensions. Fines and colloidal particles including clay, iron oxides and bacteria are ubiquitous in subsurface flow. These elements have numerous applications, for...
At a fundamental level, the macroscopic response of granular media depends on the spatial organization of contact forces between grains—the so-called ‘force chains.’ Despite their critical importance, force chains in granular media have been characterized and analyzed almost exclusively in 2D systems. To address this knowledge gap, we recently developed a new approach: a tomographic imaging...
In depleted gas fields considered for CO₂ storage, rapid pressure drops and Joule–Thomson cooling can shift near-well conditions into the hydrate stability region, where hydrate may influence injectivity. Predicting hydrate impacts remains challenging because nucleation, growth, and dissociation depend on pore-scale two-phase morphology, contact-line physics, and coupled transport processes...
Porous media performance is governed by three-dimensional microstructure, while engineering decisions aimed at improving performance require robust and reproducible links between structure, transport properties, and mechanical response. Addressing this challenge calls for integrated, physics-based workflows that consistently connect pore-scale structure to macroscopic behavior.
This...
Predictive modelling of relative permeabilities in representative carbonate samples remains a challenging problem in the Digital Rock Physics (DRP) community. Traditional DRP workflow, comprising of image acquisition and pore network model (PNM) extraction and simulation [1] is verified against homogeneous rock samples, fails to capture sub-micron porosity, prominent in carbonates. Recent...
For decades, multiple studies have focused on test methods to characterize the permeability of fabrics (in plane and transverse permeabilities), both numerically and experimentally [1], [2]. Experimental micro- and macro-models for the characterization of flow in porous media have also been widely studied by the geology community [3], with major applications in gas and petroleum extraction....
For the purpose of modeling the mechanics of granular materials, the Discrete Element Method (DEM) is a convenient computational approach thanks to its direct description of grain-scale phenomena. For the DEM to output a predictive mechanical behavior, a faithful shape description of the physical grains is logically necessary, unless the contact model between numerically-simplified spherical...
Evaporation of brine leads to salt precipitation, which can clog pores and affect further evaporation and reactions. The transport of vapor and liquid, reactions and the intricate feedback of these with change in transport properties are influenced by microstructural heterogeneity at the pore (micron to cm) scale, however their impact is felt at scales of meters and above. Evaporation-induced...
Crystallization Of Sodium Chloride In Microfluidic Pore Systems
Keywords: Microfluidics, Porous Media, Salt Crystallization, SEM
Salt crystallization in porous media induced by drying involves complex coupling between drying kinetics, wettability phenomena, pore size and salt structure 1. In this context,...
Carbon Capture and Storage (CCS) plays a vital role in mitigating adverse climate impacts. To enhance its economic viability, addressing technical challenges in CCS operations is essential. One significant challenge is salt precipitation near the injection wellbore, typically occurring within 1–2 years of CO₂ injection into deep saline aquifers [1]. The severity of this precipitation not only...
During CO₂ injection into saline aquifers, evaporation occurs at gas–brine interfaces, resulting in increased salinity and the potential for salt precipitation. At the pore scale, precipitated salt progressively reduces pore and throat radii, impairing permeability and injectivity during CO₂ storage.
We develop a pore-network modelling framework to investigate salt precipitation during CO₂...
Evaporation-driven salt transport and precipitation in porous media is a complex multiphysics process affecting numerous natural and engineered systems, including salt-affected agricultural soils, porous building material degradation, saline aquifer CO2 storage, and solar-driven interfacial desalination. Dynamic pore-network models (DPNMs) can resolve these processes but suffer from severe...
Pore-Network Models (PNM) provide a computationally efficient framework for simulating flow in porous media. However, many economically significant carbonate reservoirs exhibit multiscale porosity: a term identifying a pore space with sizes spanning multiple orders of magnitude. When using PNM approaches, two main challenges arise: imaging resolution and computational complexity. Resolution...
Microfluidic experiments in transparent, engineered micromodels that replicate porous media enable direct visualization of pore-scale processes and their connection to macroscopic behavior (Wu et al., 2020). Pore-scale simulations, in particular dynamic pore-network modeling, complement these experiments by including pore-scale interactions that are typically averaged out in continuum-scale...
Understanding immiscible two-phase flow in rough-walled fractures is essential for predicting subsurface fluid migration in fractured media, with direct relevance to applications such as CO$_2$ sequestration in depleted fractured reservoirs, where storage reliability must be ensured, and contaminant remediation in fractured aquifers, where safe and efficient injection, containment, and...
Pore-scale modeling of heterogeneous materials is challenging for a variety of reasons, many of them centered around maintaining accuracy over multiple scales. For direct computational methods (i.e., those that operate on underlying grids or meshes, rather than pore-network modeling for instance), the challenge includes efficient distribution of grid nodes – ensuring sufficient resolution in...
Low-salinity waterflooding (LSW) has emerged as a promising enhanced oil recovery method in carbonate reservoirs, yet the pore-scale mechanisms by which brine composition alters rock wettability and mobilizes trapped oil remain incompletely understood. In this work, we develop a pore-scale numerical framework that couples multiphase flow, solute transport, and surface-complexation-based...
A thorough understanding of how food matrices influence liquid permeation is essential for the optimization of filling and coating processes in food manufacturing. To this end, in this study, on the one hand, bread—widely consumed and commonly used as a carrier for sauces—is selected as a representative food matrix. On the other hand, power-law fluids—which can capture the rheological...
A volumetric lattice Boltzmann method implemented on a GPU-accelerated algorithm is employed to simulate conjugate heat transfer coupled with single-phase flow in porous media. By systematically varying the injection velocity, thermal diffusivity, and structural heterogeneity, the proposed model explicitly resolves local thermal non-equilibrium between the fluid and solid phases induced by...
Nanoporous thin materials are of central importance for membrane-based applications ranging from hydrogen fuel cells and desalination to CO2 separation and biomedical devices.[1,2] State-of-the-art micrometer-thick polymer membranes exhibit suboptimal performance due to low ionic conductivity, reactant crossover, and high production costs.[3,4] Because ionic conductivity scales inversely with...
Three-phase flow in porous media is encountered in several recovery and storage operations in subsurface reservoirs, including water-alternate-gas injections for improved oil recovery as well as permanent CO2 storage and seasonal gas storage in reservoirs containing residual oil. Such fluid injections are often slug-wise or cyclic, leading to multiple irreversible drainage and imbibition...
