Mixing occurs when two miscible fluids are brought into contact. Dispersion is a homogenized manifestation of the mixing process, which averages velocity and concentration fluctuations that cannot be resolved at the scale of observation. Shear dispersion, the process of solute spreading in pipe flow, originates from the non-uniform velocity profile in a pore cross-section. Taylor dispersion is...
The interaction of fluids with different types of porous media plays an important role not only on our daily lives, but also understanding natural and industrial processes. Detailed studies of evaporation processes in porous materials are required not only to increase the fundamental understanding but also to enhance performance in engineering terms. The efficient design, operation and...
The efficient exploitation of coalbed methane (CBM) plays an important role in reducing outburst hazards, securing energy supply and reducing carbon footprint. Horizontal well cavity completion performs well in Zhengzhuang Block, China, with stable daily gas production of 10,000 m3, which was four times more than that of the adjacent fractured well. However, the stimulation mechanism of...
Optimal Bayesian Experimental Design is one of the methods for data acquisition system optimization that is frequently utilized in subsurface flow problems. In this method utility function that measures expected quality of the experiment is derived from the first principles of probability and statistics as a function of design parameters (aka sensor location). Therefore, the optimal...
Real-time subsurface flow simulation is desirable for managing groundwater resources, geothermal exploitation, carbon dioxide geological sequestration, or underground hydrogen storage. Data assimilation methods are developed to achieve this goal. However, assimilation models usually use mesh-based numerical methods. Remeshing is frequently required whenever new data to be integrated into the...
50 % waste (quarry sand) is generated during the production of ashlar. In this study, this waste material is used to produce biosandstone as new and sustainable construction material. The quarry sand used in this study is delivered by the local natural stone plant (Picard) in Krickenbach (Germany). Viewed globally, there is a high need to investigate new construction material as alternatives...
Hydrocarbon spills into the subsurface can lead to the formation of light non-aqueous phase liquids (LNAPL), i.e., a separate phase, immiscible with water, representing a long-term environmental threat. Traditionally, the presence of mobile LNAPL is evaluated by installing monitoring wells in the area of potential concern [1]. This approach, however, provides only qualitative evidence of the...
Nanofluids possess great application potential in enhanced oil recovery (EOR). However, the EOR effects and mechanisms of nanofluids with specific nanoparticles (NPs) are not clear. In the study, the molecular dynamics (MD) simulation is thus adopted to explore the displacement of trapped oil in the rough channel by various nanofluids. Our results indicate that nanofluids with hydrophilic NPs...
Understanding of heat transfer processes in subsurface fractured rocks is critical for the development of geothermal resources. One of the challenging tasks is to build models that can adequately represent the complexity of the formation geometry and subsurface processes without the extensive computation cost. Single porosity models with effective parameters are commonly used for this purpose....
Slow Sand Filters are the last step of producing drinking water in the Netherlands which play a crucial role in removing microorganisms. A biolayer formed on top few centimeters of the sand, called Schmutzdecke, plays an effective role in colloid removal. A multi scale study is performed to investigate removal efficiency of this layer and attachment mechanisms inside these filters. Pilot...
Inverse modeling plays a fundamental role in the subsurface characterization of aquifers, given the scarcity of available data. Several techniques have been proposed in the literature and tested using synthetic examples. However, one of the big criticisms of these techniques is the lack of demonstrations in real cases. In this context, this study presents the application of two of the most...
DeepAngle uses machine learning to determine contact angles between different phases in the tomography images of porous materials. The measurement of these angles in 3D can be inaccurate and time-consuming due to the discretized space of image voxels. A computationally intensive solution involves fitting and vectorizing all surfaces using an adaptable grid to measure angles between the desired...
For the performance assessment of nuclear waste repositories, a thorough analysis of the uncertainty and sensitivity of the underlying processes is necessary. Whereas a detailed experimental investigation of the final repository site is infeasible due to numerous reasons, the verification and validation of the numerical tools under realistic conditions using experimental data of underground...
The increase in plastic production is expected to exacerbate plastic waste disposal in terrestrial ecosystems. Soil represents a large reservoir for plastic wastes. Once disposed into the soil, plastic wastes interact with soil particles and biota and affect chemical, physical, and biological processes in soil (Jannesarahmadi et al., 2023). Microplastics (MPs) with distinct thermal and...
Hypothesis: in-situ recovery is an alternative to conventional mining, relying on the application of an electric potential to enhance the subsurface flow of ions. The governing physics of electrokinetic transport are electromigration and electroosmotic flow, which depend on the electric potential and excess charge adhered to mineral surfaces, respectively. Hence, mineral occurrence and its...
Understanding reactive solute transport in natural media is critical for many applications (e.g., groundwater remediation, carbon storage, and enhanced oil recovery). It has already been confirmed that solute mixing can be significantly enhanced when decreasing the saturation, which ultimately increases effective reactivity. Most studies have been conducted in steady state conditions, i.e.,...
Even though geologic carbon storage could reduce carbon emissions to the atmosphere and mitigate the impact of climate change, there are potential seismic risks and uncertainties associated with a GCS operation. Hence, we need to understand this process better before it becomes a reliable technology. However, the system of partial differential equations used to describe an induced seismicity...
Phase change materials (PCMs) can store and release heat at a relatively constant temperature. Incorporating PCMs into mixtures for backfill materials may improve their thermal energy density and thus contribute to the enhancement of borehole thermal energy storage and shallow geothermal energy systems. However, PCMs might reduce the overall heat transfer between the borehole and the...
Large-scale fracture network and fracturing fluid retention in shale reservoir will inevitably affect the stress sensitivity. We focused on different areas of shale gas flow, and design several stress sensitivity tests of matrix, unsupported fracture, supported fracture and water-bearing fracture cores. The influence of different types of fractures and fracture water content on permeability is...
The mechanical properties of highly porous materials are expressed by fabric tensors. But the structure of highly porous materials is complicated if it is not arranged periodically. In micro-mechanical schemes or homogenization, the Eshelby tensor is widely used to estimate porous materials' mechanical properties. However, the relationship between these two tensors is not known. The result...
Considerable experimental evidence in a variety of porous materials (concrete, ceramics, bones, rocks) that undergo infinitesimal deformations makes it clear that material moduli depend on the density (identified as density dependence of Young's modulus).
The phenomean of material damage is a consequence of the inhomogeneity of the body as material properties detieriorate with...
In the work of Lundström et al [1], a new concept of stormwater storage in sponge-like porous bodies (SPBs) is suggested: down-flow and up-flow SPB storage. The analytical and numerical results of the analysis based on the first principles argue that the studied up-flow model can capture and control the stormwater runoff for various conditions of Swedish design rainfalls. In the present...
In underground hydrogen storage, pore pressure cycling due to annual or more frequent gas production (depletion) and injection leads to changes in the stresses acting on the reservoir rock, which in turn lead to rock deformation. Although inelastic deformation has an important effect on the physical properties of the rock, its effect on rock mechanical and transport properties is not well...
In the current times, the protection of the environment is becoming more and more important in all sectors. This also includes agriculture, which has to overcome particularly large hurdles in this respect, since on the one hand the world population is steadily increasing and thus more people have to be fed, but on the other hand the usable land is limited. Therefore, the yield must be...
Nuclear energy will play a key role in the UK’s strategy to achieve net zero carbon by 2050. However, the high cost and intergenerational burden of decommissioning and waste management remains high and there is a need to reduce the costs of decommissioning and clean-up. Nuclear site decommissioning involves the retrieval and handling of various radioactive waste forms. Removal of particulate...
Redox flow batteries are a promising option for large-scale energy storage, but their stringent cost requirements hinder widespread deployment. One option to increase cost competitiveness is by improving the power density of the electrochemical cell by enhancing the performance of the porous electrode microstructure, which determines the available surface area for electrochemical reactions,...
With a share of about 8.6 % of anthropogenic CO2 emissions, concrete is a major contributor to global warming. Microbiologically induced calcium carbonate precipitation (MICP) offers the potential of a more sustainable alternative. During MICP calcium carbonate is formed by microbiological activity and can serve as a binder between mineral particles. This calcium carbonate can be an...
We focus on the evaluation of the adsorption energy (EAd) of 24 Iodinated contrast media agents (ICMs) on activated carbon through Density Functional Theory (DFT) in silico simulations. The study is motivated by the emergence of concerns related to the impact of pharmaceuticals on the environment and human health [1,2]. Iodinated contrast media agents are typically used in radiology, primarily...
As countries around the world are trying to transition away from fossil fuels to renewable energy sources, short- and long-term storage of an increasing, yet unsteady, renewable energy supply becomes a major challenge. Further, as provision of heat is a major part of industrialized countries’ energy needs, storing heat energy, in applications such as the capturing of excess heat from...
Despite being major contributors to global CO$_{2}$ emissions, fossil feedstocks are finite natural resources frequently used to produce high value goods including fuels and plastics. One alternative is to replace fossil feedstocks with renewable agricultural feedstocks due to their ability to sequester carbon during growth. While a promising alternative, the use of food crops as feedstocks...
In the context of climate change, studies of water transfer in bio-sourced materials are becoming essential in order to meet the multiple challenges of developing high-performance materials over the long term and preserving resources while limiting greenhouse gas emissions. One of the keys to supporting these studies is access to the "water status" in these porous materials [1]. However, the...
Controllable but realistic representation of subsurface gas storage scenarios are needed to assess the impacts that microbial processes could have on behaviour of stored gas in hydrogen storage. Current experimental approaches may misrepresent the type and magnitude of microbial activity as they do not consider the limited residual water available as habitats for microorganisms. Understanding...
Geothermal energy is a renewable resource that may help to provide a green energy supply, although the low rock permeability at the required depth prevents an energy-efficient use of this resource. Enhanced Geothermal Systems (EGS) allow to increase permeability by means of the hydraulic stimulation of the fractures of underground formations. However, it implies risks as, for instance, induced...
In this presentation we are interested in operational applications and new numerical approaches for modeling the heterogeneous mucus bio-film of human lungs for the monitoring of cystic fibrosis (CF) therapies. At an operational level, we aim at predicting whether a therapy has a significant impact of the mucociliary clearance or not, that is to say predicting the ability of the respiratory...
Fractured sorptive geomaterials (FSG) are ubiquitous in geological systems such as coal, shale and chalk. The solid matrix of FSG can adsorb species in gas or liquid form, the process of which is often accompanied by the deformation and micro- structural alternation of the matrix. Such coupling is further obscured by the presence of fracture network, introducing complex fracture–matrix...
Ion-exchange membranes(IEMs) have been widely used for desalinated and energy conversion processes. Since the IEMs determine the efficiency of the above process, it is necessary to develop them with impoved separation performance and durability. Novel composite-type anion- or cation- exchange membranes were prepared as follows; first, pore-filling of monomer mixtures (styrene/ divinylbenzene...
Quantitative characterization of pore structure and analysis of seepage characteristics of tight reservoir based on digital core and NMR
Meng Du1,2,3, Zhengming Yang*1,2,3, Weifeng Lv2,4, Xinliang Chen2,3, Wen Li2,4
1 University of Chinese Academy of Sciences, Beijing 100049, China;
2 Institute of Porous Flow & Fluid Mechanics, Chinese Academy of Sciences, Langfang 065007, China;
3...
Water in natural environments consists of many ions, which exert electric forces on each other. We discuss whether the coulombic effects are relevant in describing mixing and reaction processes in natural environments or laboratory experiments. A typical model for electric interactions in dilute aqueous solutions is the Nernst–Planck equation.
Using FEniCS (fenicsproject.org) and Reaktoro...
Over the past decade non-destructive imaging methods for materials have been increasingly advanced. Two most notable imaging methods include X-ray computed microtomography (μCT) that can image materials at sub-micron scale to millimeter scale resolutions and focused ion beam-scanning electron microscopy (FIB-SEM) that can image at a nano-meter scale. Hence, the segmentation of images obtained...
Aiming at the changes of temperature field and velocity field caused by high temperature and high pressure fluid injected into reservoir porous medium during heavy oil thermal recovery process, based on Darcy's law, thecoupled equation of heat flow in porous media was established by the finite volume method. Based on the REV-scale porous media model, the effect of permeability and volume...
Progress towards a net zero carbon economy involves subsurface activities, such as geothermal energy production and geological storage of carbon dioxide, hydrogen and radioactive waste, that disturb tectonic stresses in the Earth’s crust. Seismicity induced by such stress perturbations is associated with risk from damage due to ground motion, fluid leakage and pollution due to increased...
In the study of solute transport in porous media, it is common to rely on the Advection Dispersion Equation (ADE) model to interpret effluent breakthrough curves (BTCs) post unidirectional tracer laboratory tests. However, this approach is not suitable for porous rocks, as these are characterised by transport processes that occur over a wide range of length- and temporal scales. To deliver...
The risk of environmental pollution, particularly groundwater contamination, has increased over the last century as a result of the growth of industry. Light non-aqueous phase liquids (LNAPLs) are one of the most common contaminants and refined petroleum hydrocarbons (RPHs-diesel, gasoline, motor oil, etc.) are typical examples [1, 2]. Heterogeneity in the subsurface represents one of the main...
Abstract: There is still more residual oil in heterogeneous reservoirs after water injection, and it is difficult to recover them by further water flooding. As a common gas flooding medium, CO2 can further improve the recovery of heterogeneous reservoirs after water flooding, so it is of great significance to study the laws of CO2 miscible flooding under different...
Plume deformation and mixing determines the effective reaction in porous media
chracterised by internal heterogeneous reaction. Via pore-scale simulations, we show the dynamic of a passive scalar injected in a packed bed consisting of a mixture of chemically inert and reactive spherical particles (adorbers), to mimic, e.g., the contaminat uptake by a fraction of grains in the soil matrix...
With the recent COVID-19 pandemic, different viruses in the environment and their disastrous effects has drawn the sharp attention of researchers and scientists worldwide. In recent years, the release of viruses has been a serious concern around the globe.
This inspired us to investigate more about what happens once a virus is released. Deciphering how various virus species act in a system of...
Hierarchical porosities consist of small, often nano-scaled pores as well as large, macroscopic pores to simultaneously achieve large inner surfaces in combination with optimized mass transport. The investigation of the capillary dynamics within optically opaque hierarchically porous membranes necessitates sophisticated microscopy techniques. First hints to unveil the dynamics are obtained...
Groundwater monitoring is the most widely used technique to detect non-aqueous phase liquid (NAPL) leakage from underground storage tanks. However, this method allows the detection of leakage as soon as the pollutants reach the groundwater table, dissolve, and move forward to the monitoring wells. In addition, this technique is often expensive and has to be accurate enough to allow rapid...
The demand for biobased, biodegradable, recyclable, and recycled material is a growing market. The consumers and policies in European countries encourage the circular economy and the replacement of single-use plastic packaging. Cellulose fibrous materials, as a unique source recyclable and biodegradable, offer an alternative economical and technological solution to the problems caused by...
Rivers and streams are important for transporting minerals, nutrients, and other chemicals
throughout the natural environment. Introducing potentially toxic species into local water
systems, e.g. agricultural-based pesticides, may have negative ecological consequences. Hence,
understanding how materials are transported in hydrologic systems is important for developing
more...
Microbially-induced carbonate precipitation (MICP) may be used to improve soil strength. The method relies on the total or partial saturation of the porous medium with a calcifying bacterial suspension. The project presented here focuses on filling the porosity of granular packings using bacterial liquid foam in order to achieve low liquid saturation. In addition to saving liquid, the foam...
Biochar is a carbonaceous porous material with wide range of applications. Biochar is produced via pyrolysis of organic material such as agricultural or forestry waste. Some examples of possible applications are fertiliser production, carbon storage, and water/soil decontamination (Cao et al., 2009). Biochar can be produced from waste material, such as manure, sawdust, or wastewater sludge...
Groundwater aquifer systems serve as a major source of drinking and irrigation water supply. In recent years, they have also become valuable for geothermal energy applications. The protection of groundwater against detrimental factors is crucial to preserve this valuable water supply and ensure a sustainable energy transition. Subsurface contamination by dense non-aqueous phase liquids...
The utilization of microchips to study fluid flow processes in porous media has gained high popularity in recent years. The silicon structures between two glass plates allow the visual observation of various processes (e.g., EOR and microbiology during underground hydrogen storage) and assess their suitability for large-scale applications. Nowadays, a wide field of designs ranging from...
Over the past three decades, digital rock physics (DRP) has become a complementary part of the field of study to understand better the behavior of porous media at the micro-scale. In this study, we apply the established five-step DRP workflow to a concrete specimen (e.g., Wildenschild et al. 2002; Schlüter et al. 2014) : (1) Preparation of a high-resolution X-ray computed tomography (XRCT)...
The transport of moisture and heat through building materials ultimately dictates their insulation performance over its lifetime. However, characterisation of building materials is challenging because porous building materials are heterogeneous and their macroscopic physical properties (e.g. permeability, thermal, and mechanical) depend on their micro scale characteristics, i.e. the local...
Fluid flow in fractured porous media is concerned with various processes in science and engineering, including transport, chemical and mechanical processes, etc. Direct numerical simulations of fluid flow can investigate pore-scale processes and flow mechanisms in fractured permeable media. However, the tremendous computational costs prevent these methods from being applied to larger-scale...
Freezing and thawing of water in porous media depend on pore size distribution and shape of particles. Magnetic resonance imaging (MRI) of the freezing and thawing process was performed on two samples of different porous materials, each one in two replicates. The experiment was subsequently numerically simulated. The set-up consisted of a double-walled Plexiglas container. The inner...
The porous properties highly determine the physical properties of materials like density, stiffness and flow transport properties. This poster wants to contribute to the question whether knitted pore systems can be designed and optimized for highly functional garments like sportswear or be used as functional carriers in technical products or processes. In a new combined wicking and drying...
Entrapment of the non-wetting phase in porous media has been observed in a variety of fields such as petroleum engineering or geological storage of carbon dioxide. Our study aims to monitor gas trapping under in-situ conditions using X-ray computed micro-tomography to evaluate gas trapping as a possible mechanism for a decreasing productivity index of geothermal reservoirs. The transient...
Packed beds or granular systems and sintered or fibrous porous media are of specific interest in geosciences, the chemical industry, battery technologies and electrochemical cells. In these systems, the geometry and size of the pore space depends on the particle shape [1]. Heat transport through the porous packed beds strongly depends on the tortuosity of the pore space, as it forms a...
In order to slow the rapidly deteriorating climate crisis we need to drastically increase our use of cleaner, more renewable energy sources. Given that renewable sources are often subject to seasonal variations, the question of what to do with the excess energy has the potential to be answered by underground hydrogen storage systems. The transport of CO2 and natural gases in underground...
Renewable energy sources have a significant disadvantage as building blocks of a decarbonized energy system: they rely heavily on weather conditions, which can cause fluctuations in energy generation. To address this issue, hydrogen (H2) is increasingly being seen as a viable way to transport excess energy generated by renewable sources, preventing imbalances in energy supply. However, storing...
Access to clean water have been a growing problem for both developed and underdeveloped countries. To curtail this growing problem, water treatment must be considered. Conventional methods such as chemical precipitation, ion exchange, adsorption (using activated carbon), and membrane separation processes are applied in the removal of contaminants from water. These methods are costly and often...
Understanding flow and transport through fractured porous media is vital for optimising large-scale hydrological and geological processes such as carbon capture and storage, geothermal energy production, and contaminant transport. Direct Numerical Simulations (DNS) solving the Navier-Stokes equations can accurately describe species transport through relatively small volumes of porous media....
Better understanding the complex poromechanics of fluid-saturated fractured rock is important to numerous areas in the exploitation of subsurface resources. Fluid pressure diffusion (FPD) between fractures and the embedding porous matrix and/or between interconnected fractures can be a significant source of intrinsic seismic wave attenuation and dispersion, as indicated by theoretical studies...
Asbestos is a well-known and regulated air pollutant and it is indeed classified as a carcinogenic compound of the first group. However, several studies recently reported asbestos presence also in fresh water sources, such as lakes, rivers, groundwater and drinking water. As far as human exposure, two main pathways can be identified for waterborne asbestos: (i) inhalation due to water...
Solute mixing in porous media plays a fundamental role in a variety of contexts, e.g., environmental risk assessment, geochemical reactive transport. Mixing dynamics are strongly impacted by the heterogeneity of the hosting porous media which leads to inhomogeneity of concentration within the spreading and the mixing volume. Considering Darcy’s scale heterogeneous formations, we develop a...
Concrete is the most consumed artificial material universally, and its production is responsible for about 1.5% of the UK's greenhouse emissions (Hibbert et al., 2022). Concrete assets are often exposed to harsh environmental conditions, including exposure to seawater, freeze-thaw cycles and temperature cycles, leading to degradation of the matrix. Reducing the permeability of degraded...
Patrick Jasek 1, Hannes Koneggerv2,Saeid Sadeghnejad 3, Frieder Enzmann 3,Andreas Loibner 2, Holger Ott 3
1 Department Petroleum Engineering, Montanuniversität Leoben, 8700 Leoben, Austria
2 Institut für Umweltbiotechnologie, Universität für Bodenkultur Wien,3430 Tulln an der Donau, Austria
3 Institut für Geowissenschaften, Johannes Gutenberg-Universität Mainz, D-55128 Mainz
The...
Numerical simulations of reactive transport in fractured porous media are necessary for several environmental and engineering applications. Networks of fractures may behave as shortcuts for the transport processes, whereas chemical reactions trigger mineral dissolution and precipitation that alter the porous medium and fracture walls locally. This will either cement flow paths or open new...
Natural subsurface systems are often composed by multiple geomaterials, constituting the internal architecture of the system, characterized by uncertain spatial distribution. This leads to incomplete knowledge of the material properties. Here we address uncertainty arising from the lack of knowledge on location of boundary interfaces between geomaterials and their influence on physical...
Transport processes and mechanical properties of porous media are extensively related to microscopic features of the pore structure, and especially to the pore size distribution (PSD). Unlike with other soil characteristics, e.g., porosity and specific surface area, for which there is a consensus over the estimation approach, the available methods for estimating PSDs are often costly and...
Ion-exchange membranes(IEMs) have been widely used for desalinating electrodialysis and energy conversion processes. Since the IEMs determine the efficiency of the above process, it is necessary to develop them with improved separation performance and durability. Novel composite-type anion- or cation- exchange membranes were prepared as follows; first, pore-filling of monomer mixtures...
Thermal degradation is a key element that determines the success of polymer projects. The published work conducted on commercial polymers such as HPAM has suggested the infeasibility of polymers used in harsh reservoir environments. Nonetheless, with recent advances in polymer technology interest in numerical simulation evaluation on field-scale harsh reservoir environments has revived. In...
We present a spatially and temporaly explicit mathematical model for root-soil interaction at the microscale. This includes a cellular automaton model for dynamic rearrangement of soil particles combined with a particulate organic matter turnover model. Additionally, the impact of root growth and root exudates and their distribution into the soil on soil aggregation and stability are taken...
Multiphase flow in porous materials is conventionally described by an empirical extension to Darcy's law, which assumes that the pressure gradient is proportional to the flow rate. Through a series of bench and pore-scale imaging two-phase flow experiments, we demonstrate that even when capillary forces are dominant at the pore scale, there is a nonlinear intermittent flow regime with a...
Rhizosphere differs from bulk soil due to the presence of root mucilage, which affects physical, chemical, and microbial processes. It is well known that the rhizosphere responds slowly to water potential changes, which buffers changes in water content and helps keep the rhizosphere wetter than bulk soil during drying. Mucilage can affect solute transport and gas diffusion by affecting the...
Geothermal power output and the associated heat depletion in hydrothermal doublet systems depend largely on the existing reservoir and operational conditions. In this study, we use CMG-STARS Simulator to numerically simulate the temperature depletion of a homogeneous, horizontal hydrothermal reservoir in Western Saudi Arabia due to geothermal exploitation by a well doublet. We vary the...
Solute dispersion in heterogeneous porous media is classically parameterized by Fickian-type macrodispersion concepts, matching the rate of change of second central spatial moments. As diffusion is an irreversible process, the second central moments computed by a Fickian macrodispersion model can only increase – also upon flow reversal. By contrast, if solute transport was strictly advective,...
Convective mixing is present in a large assortment of natural and industrial processes, such as in carbon capture and sequestration, where it ensures a safer storage of carbon dioxide, seawater intrusion, high-level radioactive waste disposal sites and geothermal energy production. In this work, we study the effect of the heterogeneity on the behavior of convective mixing since most of the...
The hydrological cycle is highly affected by changes in vegetation cover. One of the most important forces in this cycle is transpiration. This process returns approximately 50% of precipitated water back to the atmosphere, and accounts for more than 60% of the evapotranspiration rate. Vegetation is thus exposed to and governed by different meteorological variables, as well as by the...
The remediation of contaminated soils is an environmental critical issue. A common form of contamination is caused by heavy chlorinated solvents spills, commonly used in industrial processes [1]. Also, remediation is particularly challenging when these pollutants are present in multi-layered soils [2]. A promising approach for the treatment of these soils is the use of polymer solutions [3]....
Introduction: This work aims to conduct, interpret and derive the multi-phase fluid flow behaviour more efficiently and feasibly from microfluidic experiments. The goal is to conduct SCAL experiments using a microfluidic setup on a chip. Additionally, interpret the in-situ results, where the parameters influencing the multi-phase fluid flow in porous media, such as wettability, capillary...
The sea level has risen notably in recent decades compared to the most recent millennia. This exposes coastal areas to hazards ranging from enhanced flooding and erosion to groundwater contamination and soil salinization referring to excess salt accumulation to a degree that adversely influences soil and environmental health (Hassani et al., 2020, 2021). This study focuses on how soil...
Granular activated carbon (GAC) produced from the thermochemical treatment of biomass wastes can be valorized as a low-cost adsorbent for the removal of various types of pollutants from water streams. Several GACs were prepared from banana peels and coffee wastes with their chemical activation by acids or alkalis and subsequent pyrolysis in a tubular furnace at temperatures ranging from 500 to...
Microfluidic devices offer unique opportunities to directly observe multiphase flow in porous media. However, they face difficulties in representing steady multiphase flow without fluctuating occupancy of locations in the network. The ability of two phases to form steady, intertwined flow pathways is a key property of 3D pore networks (Sahimi, 1994; King and Masihi, 2019). This is not possible...
The injection of hot water into coal seam has both negative and positive effects on the production of CBM (Coalbed Methane). In terms of the negative effect, when the water is entering the pore network in coal, the relative saturation and permeability of gas are reduced and lead to the water-lock phenomenon dominated by capillary force, which prevents the migration of CBM. In terms of the...
For the field development planning for carbon capture and sequestration and the underground storage of hydrogen, it is important to have a consistent set of relative permeability and capillary pressure-saturation functions. Regulatory requirements and minimum standards of operators may require conducting these measurements with well-established industrial protocols which have been developed...
Following the need for clean energy transit and lowering carbon emissions, many electrochemical devices have been put out as energy storage tools such as fuel cells, batteries, supercapacitors, etc. all these applications require electrodes with high surface area, good flow, and mass transport hosts active material and releases bubbles. For these properties, we introduce porosity into our...
It is estimated that 50% of world oil production comes from naturally fractured carbonate reservoirs. One of the biggest challenges in this type of formation is its heterogeneous nature. Besides the presence of fractures that longitudinally connect the porous media, vugs at different scales and distributions are scattered throughout the porous matrix. These cavities cause fluid flow...
Dust emission induced by wind erosion affects crop production, the aviation industry, and human health, to name a few. Wind-borne dust particles can have several environmental and health implications. They can carry pathogenic microorganisms and thereby pose health threats. Besides, having entered surface water and oceans, they change water chemistry and quality, subsequently affecting the...
Multiphase fluid flows frequently occur in nature and industrial applications including microfluidic devices, enhanced oil recovery, CO2 storage, etc. In order to have a better understanding of multiphase physics, several numerical methods have been developed over the past. The lattice Boltzmann method (LBM) as an alternative to the classical computation fluid dynamic (CFD) method has received...
Presented here is a model of soil-fluid-structure interaction that integrates soil mechanics (saturated sediments), fluid mechanics (seawater or air), and solid mechanics (structures). As a result of this formulation, the Material Point Method, which simulates large deformations of the porous media and the structure, is combined with the Implicit Continuous-fluid Eulerian, which simulates...
In this work we derive a model for a deformable porous medium with a growing interface and with phase change to model eco-hydro-mechanical problems in which there is a continuous deposition of porous substrate on the surface and the simultaneous decay and phase change between solid and fluid. The model will then be simplified for one-dimensional scenarios or in multi-dimension under small...
The characterization of adsorbents has been long established in material science. However, the interplay of adsorptive and mechanical response (such as induced strain and stress) at high pressure and high stress is relatively new. The typical dilatometer test used in adsorption science is just one particular case of the full range of poroelastic response with varing fluid (pore) pressure and...
One of the key stages in materials recycling is their crushing into finer elements, i.e. granular material or powder to be sorted and re-used. Insofar as the crushing stage is already very energy-intensive, there is an interest in recycling the crushed elements as directly as possible. In a certain number of cases, simple shaping using a binder, and a possible post-treatment of the peripheral...
The dissolution trapping of CO2 in water, often accelerated by gravity-driven convection of overlying CO2 plume in high permeable water-saturated rocks, can ensure safe long-term sequestration of CO2 but can take thousands of years in low permeable rocks (< 1 mD). We hypothesize that in naturally fractured reservoirs, even with low to no fracture network connectivity, the density-driven...
Dissolution/precipitation processes in reactive transport in porous media are ubiquitous in a multitude of contexts within the field of Earth sciences, such as geological hydrogen and carbon storage, reactive contaminant transport and acid injection in petroleum reservoirs. In particular, the dynamic feedback between the reactive process and solute transport, capable of giving rise to the...
Subsurface porous systems, like soils and aquifers, are physically and chemically highly heterogeneous. Especially on the microscale, chemical hot spots and heterogeneous pore-sizes, which lead to a wide range of fluid flow velocities and strong local gradients, control the physico-chemical landscape. Microorganisms capable of biasing their motion to swim along these chemical gradients – known...
Over the last 15 years there has been increasing interest in the use of microbially-induced biomineralisation processes for a range of civil, structural and environmental engineering applications including for rock fracture grouting, soil stabilisation, well sealing, stone and concrete protection/repair and bioremediation. Most studies have focused on investigating calcium carbonate...
Fungi are the largest source of biomass within soils, yet fungi are frequently neglected within the environmental microbiology and environmental science research disciplines (Gadd et al., 2007). Fungi are known to play vital roles in soils: as symbionts with plants, as decomposers and in elemental cycling. Furthermore, basidiomycota fungi have been shown to successfully degrade organic...
Shale oil and gas is becoming increasingly crucial for unconventional oil and gas exploration and development worldwide. The pore structure determines the transport properties in shale oil and gas reservoirs, which affects the assessment and development of shale oil and gas potential. Shale oil and gas reservoirs develop multi-scale and multi-type pore structures ranging from nanometers to...
Diffusiophoresis [1, 2] referring to the colloidal particle migration triggered by gradients of local salt concentration, has been established in the recent years as an efficient particle manipulation tool in relatively simple microfluidic setups such as plane channels [3], dead-end pores [4], Y-shaped channels [5], vertical diverging pores [6], etc. Owing to the fact that the particle...
Quantifying reservoir property is one of the most crucial works of petroleum exploration and production. Determining transport properties in reservoir rocks requires accurately quantifying the pore system. The study of the pore structure in porous media is to understand the processes of single and multiphase fluid flow. Quantification of the pore system in reservoir rocks at large scale is...
Drag reducing agents (DRAs) are molecules that are able to reduce the frictional losses in turbulent flows. Typical examples are high molecular weight polymers, or surfactants that form worm-like micelles. DRAs are widely used in industrial applications : for example they can be used to reduce the pumping requirements in long pipelines such as the Trans-Alaska pipeline (1), to increase the...
CO2 flow in porous media often results in poor reservoir sweep efficiency. To mitigate this problem alternate injection of a polymer solution and CO2, known as Polymer-assisted Water-Alternating-Gas (PA-WAG), is applied. The objective of PA-WAG is to improve mobility control, thus sweeping a larger part of the reservoir. Therefore, it is of great importance to study the effect of CO2 and...
Research on the advancement and optimization of the PEMFC for commercialization centers around improving one or more of its limitations which include slow oxygen reduction kinetics, poor heat and water management, CO poisoning, and sourcing high-quality hydrogen as a fuel. Water management and subsequent improvement of oxygen reduction kinetics have been studied experimentally, numerically,...
The dynamics of a migrating chemical plume in a porous medium can be affected by different chemical processes (e.g., sorption, retention, precipitation and dissolution, complexation, reaction), as well as by the physical properties of the medium and flow field (heterogeneity of the medium, porosity and permeability, fluid velocity). Groundwater input in natural systems can vary over a wide...
It has been four decades since Wilkinson and Willemsen [1] introduced a new, at the time, theory of percolation, the invasion-percolation theory, as they named it. The concept was based on the fact that a displacement process between two immiscible fluids is capillarity-driven, but can be applied also in cases where the path of lowest resistance is followed. It involves the use of the fractal...
During imbibition, fluid-fluid interface at the inlet of a constriction experiences an increase in capillary force that results in rapid fluid invasion known as Haines jump (Haines, 1930). During drainage, the interface gets pinned at the end of the constriction, which causes p-s trajectories to follow different paths during imbibition and drainage resulting in p-s hysteresis. In this work, we...
Petrophysical rock properties (i.e., porosity, absolute and relative permeabilities) are key information for any reservoir characterization and represent fundamental input parameters for the simulation studies. To access to such information typically core analysis are needed. Although core analysis tests are an accurate way to obtain such properties (Gaafar et al. 2015), there are cases where...
GeoChemFoam is an open-source toolbox for modelling flow processes in porous media images. It is based on OpenFOAM, the open-source Computational Fluid Dynamics (CFD) toolbox, and includes many additional packages that extend the software to more complex physics, including multiphase reactive transport, heat transfer and mineral dissolution, which are essential for modelling porous media...
Underground hydrogen storage can store grid-scale energy for balancing both short-term and long-term inter-seasonal supply and demand. However, there is no numerical simulator which is dedicated to the design and optimisation of such energy storage technology at grid scale. A novel multi-phase simulator, GPSFLOW (General Purpose Subsurface Flow Simulator), has been developed...
Understanding and mastering gelation of biopolymer is important for controlling the structure of the gels and open the way to the design of micro-objects with a gradient of physical properties. In this study, we investigated the gelation between a calcium solution and a suspension of biopolymers. We showed that spontaneous osmotic flow through the gel controls its formation and can be used to...
Solute mixing in steady porous media flows is easy in three dimensions. Flows elongate solute filaments exponentially fast, and this "chaotic" elongation enables molecular diffusion to rapidly produce uniformity. In two dimensional steady flows, filament elongation is much slower, meaning mixing can be far less efficient. However, many porous media such as biological tissues and geological...
We design porous geometries with different grain organizations and embed these in novel microfluidics set-ups to directly assess hydraulic attributes of porous media as a function of the degree of structural complexity of the pore space. A variety of studies have documented the relationship between the overall flow and pressure drops for homogeneous permeable media. Otherwise, the fundamental...
The relative permeabilities of multiphase fluid systems depend on saturation history as has been shown by experimental, numerical, and field studies. Such hysteresis is especially relevant in underground hydrogen storage (UHS). UHS projects involve temporary storage of hydrogen in the porous subsurface on a seasonal timescale. The injection and production of hydrogen over the span of several...
The displacement of one wetting fluid by another immiscible fluid, i.e., dewetting, in a confined geometry is an essential process in many engineering practices, including enhanced oil recovery, NAPL removal, and microfluidics. For dewetting in uniform tubes, the fluid-fluid interface loses stability once the dewetting velocity attains a threshold and a liquid film is entrained. In this work,...
Virus pandemics and endemics cause enormous pain and economic, political, and social costs and turmoil. While the Covid19 pandemics induced obvious damages, the "silent" Hepatitis C virus (HCV) infection induced liver destruction is the main reason for liver transplants. HCV virus replication sometimes serves as some sort of representative to study virus replication basics. HCV-generated...
Understanding the mass transfer of CO$_{2}$ into formation brine both qualitatively and quantitatively is important for improving the security of geologic carbon sequestration. In this study, quasi-dynamic X-ray micro-computed tomographic (MCT) imaging was used to track the time-evolution of supercritical CO$_{2}$ (scCO$_{2}$) clusters in a sandstone throughout brine injection. A...
(1. University of Chinese Academy of Sciences, Beijing 100049, China;2. Institute of Porous Flow & Fluid Mechanics, Chinese Academy of Sciences, Langfang 065007, China; 3. Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China; 4. State Key Laboratory of Enhanced Oil Recovery, Beijing 100083, China)
Abstract: In order to explore how to improve the...
Hydrogen is a promising alternative to carbon based energy carriers and may be stored in large quantities in subsurface storage deposits. We investigate the impact of static properties, which are density and phase equilibria, as well as the impact of dynamic properties, being viscosity and diffusion coefficients, on the pressure field during the injection and extraction of hydrogen in the...
Introduction
Understanding the fundamental mechanism of the hydromechanical process and fluid leakage is crucial in modeling fractured reservoirs. Traditional simulation methods often assume impermeable and rigid fracture walls, which neglects the effects of fracture deformation and fluid leakage. This work introduces a Darcy-Brinkman-Stokes method to capture the effects of fracture...
Temperature-dependent resonant frequency measurements via the impulse excitation technique (IET) can be used to characterize the temperature dependence of elastic properties and to determine the temperature of phase transitions during repeated heating and cooling cycles. In particular, the reversible and hysteresis-free displacive phase transition between the low- and high-temperature...
Lithium-ion battery performance can be significantly affected by porous electrode microstructures. The carbon binder domain (CBD) within an electrode structure is used to enhance mechanical stability and facilitate electronic conduction. The understanding of the CBD phase microstructure and how it affects the complex coupled transport processes is crucial. Inspired by the bimodal pore size...
Cement plug is a crucial barrier material for ensuring long-term integrity of depleted wells, either where CO2 has been sequestered or in permanently abandoned wells [1]. However, some of the drilling mud used prior to the cementing operation often remain due to wetting properties of the base mud [2]. The remaining drilling mud might therefore contaminate the cement and can be detrimental to...
Well testing is a common practice that consists of wellbore pressure and flow rates data acquisition in order to estimate parameters that govern multiphase flow in a porous media. An injection-falloff-production test was originally proposed by Shi et al (2006) as a well test for the in-situ estimation of two-phase relative permeability curves. The idea is based on the concept that if a well...
As a greenhouse gas, CO2 contributes significantly to the rise in global temperatures. The concentration of CO2 in the atmosphere has increased by 45\% since the First Industrial Revolution, as a result of continuous CO2 emissions. In order to reduce artificial emissions of CO2 into the atmosphere, measures must be taken. Currently, fossil fuels still dominate the energy market, and CO2...
Ultrasound wave velocities of porous media are uniquely determined by their elastic properties. In particular, in statistically iosotropic porous media the velocities of the transverse and longitudinal waves can be used to determine the effective elastic moduli and the Possion ratio. On the other hand, many model-based relations have been proposed in the literature to predict the porosity...
Digital Rock Physics (DRP) simulation provides a fast and cheap way to compute relative permeability curves of a rock/fluids system. It represents an opportunity to provide more data to Reservoir engineers and thus help them to have better petrophysical input for their simulations. In a previous work, we have shown that DRP simulation was predictive for a mixed-wet Bentheimer when coupled with...
Shrinking and swelling of expansive clay deposits can cause severe damage to infrastructure (Mokhtari & Dehghani, 2012). Volume change depends on the characteristics of the porous material, such as clay content, mineralogy, organic matter content, soil moisture conditions and drying history (Basma et al., 1996 ; Boivin et al., 2004; Puppala et al., 2007). However, predicting the shrinking and...
Bioremediation of nonaqueous phase liquid (or NAPL) contaminants may be accelerated with the presence of chemotactic bacteria that can preferentially migrate toward NAPL upon detecting its chemical gradient. In a heterogeneous porous media [1], chemotactic bacteria accumulated in dead-end pores near NAPL ganglia trapped in low-permeable regions; however, no retention was seen in bacteria near...
At the end of a production well’s life cycle, the facility must be shut down and prepared for decommissioning. This process ensures that the well site is properly sealed to prevent the migration and emission of remnant hydrocarbons that may reside within the well. This procedure is known as plug and abandonment and sees the emplacement of a series of cement-based plugs to act as this sealing...
Svelvik CO2 Field Lab is a small-scale field laboratory located about 50 km southwest of Oslo in Norway. The test site occupies an inactive part of a sand and gravel quarry, located in a glaciofluvial – glaciomarine environment. It consists of an injection well surrounded by four monitoring wells covering an area of approximately 300m x 150m. The injection well facilitates water and CO2...
Solute transport in porous materials is important in many natural and industrial applications, such as soil contamination and subsurface CO2 storage. While in many cases there is more than one fluid phase ("partially unsaturated" conditions), most studies focus on the simpler case of the single-fluid phase ("saturated"). This study investigates the effect of spatial correlations in pore sizes...
Generating a solution for the pressure in reservoir models with fine-scale heterogeneities, modeled at a meter scale, can be compute-intensive. Multiscale methods aim at reducing the runtime for the solution of Poisson-type equations by solving coarsened flow problems that account for fine-scale variations. To obtain a coarse-scale operator one needs to project the fine-scale operator using...
Space exploration has aimed to visit other planets and sample cosmic bodies within our solar system in the past decades. As these ambitions increase, new technologies and the development of lightweight porous materials are needed to design spacecraft Thermal Protection Systems (TPS) that endure the harsh environment of hypersonic atmospheric entry and ensure the safety of the payload. Current...
Geological heterogeneities in the subsurface are multiscale in nature, sparsely sampled, and hence inherently uncertain, particularly in geothermal reservoirs where the availability of geophysical and geological data is often limited. Yet, these geological heterogeneities influence the convective and conductive transport of heat in a geothermal reservoir and need to be represented adequately...
Abstract
Termite nests have long been recognised for their ability to maintain self-sustained ventilation and thermoregulation irrespective of external climatic conditions. Although there has been significant interest in this topic, especially from a point of view of designing energy-efficient buildings, the mechanisms by which the nest properties are controlled are not fully understood.
In...
More than 1.4 million clinical vertebral fractures occur annually, making them a common occurrence worldwide. The cause of vertebral fractures could be injuries resulting from accidents or osteoporosis in old age. Vertebroplasty is a commonly used procedure to treat and prevent vertebral fractures. The procedure involves injecting bone cement inside the vertebra and letting it harden by...
The geological disposal facility (GDF) is the most common planned method for the disposal of radioactive waste. GDFs utilise a multi-barrier concept designed to prevent the release of radionuclides into the surrounding environment, collectively known as the engineered barrier system (EBS). The EBS is a key component for GDF safety as it slows the inflow of water to limit corrosion, protects...
Multicomponent reactive transport codes couple biogeochemical models with solvers for flow and transport and other relevant processes. Many of these codes are the legacy of years of development and research, over which model complexity has increased incrementally. Often the complexity of implementing a comprehensive and flexible treatment of biogeochemistry is a significant obstacle to the...
Underground Hydrogen Storage (UHS) has the potential to play an important role in the transition to renewable energy resources. In geological hydrogen storage, safety and efficiency are principal factors. We want to be able to get back as much as possible of the stored hydrogen and it is important that the seal can hold the injected hydrogen. One of possible leakage paths is through caprock....
The modeling of lithium-ion cells plays an important role in the electrification of many industries, such as the automotive industry. Models with high accuracy and low computational complexity are essential for the optimization of such applications.
To achieve this, a fully homogenized macroscale (FHM) model has been proposed [1]. This reduced model is based on effective mass and charge...
Injection of a $\rm{CO_2}$-rich phase into a porous material initially saturated with water solution (i.e., drainage) leads to $\rm{CO_2}$ dissolution and mass-transfer into the resident water solution. As a result of the accompanying decrease in solution pH, the solid matrix can be in chemical disequilibrium and induce dissolution-precipitation reactions such as carbonation (i.e., carbonate...
Among the strategies that are being undertaken to decarbonize the energy sector, many options involve underground hydrogen and carbon dioxide storage facilities. Therefore, efforts are being addressed to understand and characterize flow phenomena occurring in underground porous systems.
In this context, microfluidics offers a cost-effective option to extract large sets of information at the...
The rise in greenhouse gas emissions, particularly carbon dioxide (CO$_2$), has become a significant environmental issue and is directly responsible for global warming and its harmful effects on the planet. Geological CO$_2$ storage (GCS) has emerged as a promising solution to reduce CO$_2$ emissions into the atmosphere. However, for GCS to be successful, long-term containment of CO$_2$...
Discontinuous phase flow behavior is different from that of the continuous phase flow. In addition to that, depending on factors such as the pore structure, the wettability, the discontinuous phase can exist in many forms. Each form may exhibit a specific flow behavior. Numerous studies have been performed on the mobilization of discontinuous phases. However, many works have been performed on...
The microstructure of capillary porous media partially saturated with liquid water often changes in the course of drying. This significantly affects the structural and transport properties of porous media. In this work, a discrete pore network model has been developed that allows to describe the microstructure dynamics and mass transport kinetics of a model capillary porous medium under slow...
Wetting film can develop in the corners of pore structures during imbibition in a strongly wetting porous material, which may significantly influence the two-phase flow dynamics. Due to the large scale difference between main meniscus and corner film, accurate and efficient modeling of the dynamics of corner film remains elusive. In this presentation, we develop a novel two-pressure dynamic...
The study of methane adsorption on the surface and in the interlayer space of clay minerals is of great importance for the exploration and production of natural gas and shale hydrocarbons. Substantial part of the shale gas exists in the adsorbed state, so understanding the adsorption capacity as well as mechanisms of adsorption is important to properly estimate the amount of shale gas and to...
Due to its benefits of miscibility and diffusivity with oil, which results in recovering most of the oil within its swept zone, gas EOR is typically used to reduce decline in oil production. However, gravitational segregation, gas channeling, and viscous fingering are frequent occurrences during gas EOR operations. This results in a low mobility ratio and poor volumetric sweep efficiency,...
Reservoir scale modelling of vuggy and fractured porous media requires upscaling and determining their equivalent permeability. The effect of vugs and fractures on single flow behaviour in porous media is still not fundamentally understood. Direct simulation models combining Darcy flow through the porous matrix and Stokes flow through vugs and fractures have been developed in recent years. ...
Two different types of polymer-coated nanoparticles (PNPs) were synthesized, stabilized in aqueous solutions of salts (NaCl, CaCl2) and used to prepare Pickering oil-in-water emulsions for enhanced oil recovery (EOR) from reservoir rocks: (1) PNPs of silica synthesized by free radical polymerization of the monomers 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPSA) and dodecyl methacrylate...
Wettability alteration is a widely accepted mechanism in enhanced oil recovery where modified salinity water improves oil mobilization in porous media by making reservoir rock more water wet. The equilibrium between phases in the Crude Oil-Brine-Rock (COBR) system defines the wettability state of the rock. As these properties will depend on the type of rock and crude oil it is crucial to...
Although a number of studies have been carried out, especially in recent years (e.g., Hemme and van Berk, 2018), to evaluate the chemical-physical influences of hydrogen storage in underground salt caverns, many questions still need to be answered. Because of the lack of reliable data on the effect of hydrogen on permeability and mechanical integrity in the critical lithologies, such as...
Biomineralization, through microbially, thermally, or enzyme induced carbonate precipitation (MICP/TICP/EICP), is a naturally occurring and inexpensive cementation process that can seal microfractures and pore throats that are inaccessible to cement and chemical based grouts. The porosity, permeability and thermal conductivity of porous geomaterials can therefore be controlled.
This...
Solving the inverse problem (identifying the parameters of PDEs) typically poses exceptional challenges due to the nonlinear nature of the governing equations, their strong coupling, and the extremely high dimensionality of the problem. Classical data assimilation and optimization techniques treat forward solvers as black-box estimators and therefore typically require an unfeasible number of...
Electrical transport properties through porous media have widespread applications in reservoir formation evaluation, groundwater management, mineral exploration, and carbon capture and storage (CCUS) monitoring. Additionally, advancements in 3D imaging and computing have enabled unprecedented visualization and analysis of these pore scale processes. However, relationships between a porous...
In 2022 a number of pre-exascale and exascale supercomputers had become available for scientists. We took the opportunity of the pilot phase of the LUMI supercomputer to perform a number of simulations of wormhole growth with an aim to use as much spatial information as possible. The goal was to investigate if properties of growing wormholes could be recovered if sufficient resolution is...
The fluid phase saturation degree is often used to define multiphase flow conditions in porous media macroscopically. However, the microscopic (pore-scale) fluid phases’ distribution pattern can be crucial and is usually not measured or quantified. For example, the topology and connectivity of the fluid phases impact the permeability and, thus, relative flow rates. Therefore, they will impact...
Legacy nuclear sites typically feature subterranean volumes of radiologically contaminated soil, and concrete containment structures that have deteriorated over time. Disturbances caused by surface-level decommissioning operations exacerbate the risk of radionuclide release into the environment via contaminated groundwater. Sub-surface hydraulic barriers are needed to mitigate this, but are...
Recent studies have shown that chaotic advection is spontaneously produced by laminar flows through granular media such as bead packs, strongly impacting solute mixing rates. This has strong implications for many reactive and biological processes in the subsurface. Chaotic dynamics could also be key in a wide range of environmental and industrial applications driven by mixing. Beside granular...
A novel, hybrid pore-scale simulation method using Lattice-Boltzmann (LB) coupled with Langevin-Dynamics (LD) is proposed to investigate the physics of nanoparticles onto oil/water interface. Based on the LB method, the high-resolution characterization of oil-water two-phase interface is established, independent of further adjustment of interfacial tension (IFT), density and viscosity ratio....
Reactive boundary conditions are employed to model an increasingly wide range of transport scenarios. While the capability of a variety of computational schemes for reliable description of such reaction-diffusion processes at the boundary of a given domain has been assessed in the literature, the effects of hydrodynamic processes on the rates of reactions taking place at the boundary are still...
Treatment of wood cell wall with polyethylene glycol (PEG) is a widely used technique by archaeologists and conservators to consolidate waterlogged archaeological wooden artifacts such as the Swedish warship Vasa and Henry VIII’s warship the Mary Rose. During the decade-long consolidation process of introducing PEG solution into these wooden artifacts, PEG molecules gradually diffuse into the...
Hydrocarbon-rich unconventional reservoirs are vital resources for the anticipated growth in energy demand. Spontaneous imbibition is a primary mechanism for improving shale fracturing and wettability alteration treatments in these ultralow-porosity and permeability reservoirs. Therefore, enhancing the efficiency of spontaneous imbibition is crucial to achieving higher recovery and delaying...
Diagenetic events lead to substantial variation in pore size, shape, and connectivity in carbonate rocks and porosity at multiple scales (submicron to hundreds of millimeters). This diversity in carbonate porous systems has a significant effect on petrophysical properties leading to different flow characteristics in carbonates from that of siliciclastics. In this study, we focus on the role of...
Pore-scale studies of fluid flow in porous media are of critical importance for a wide range of energy and environmental science applications, including geological sequestration of CO2, groundwater remediation, hydrocarbon production, underground energy storage, and evaluating geothermal systems. X-ray micro-CT analysis is the most widely used method to visualize and quantify pore-scale...
Solute transport in porous media plays a significant role in industrial and natural processes, since porous materials are ubiquitous on Earth. Modelling transport is important for various applications, including soil moisture dynamics, groundwater pollution, and oil recovery. Previous research suggested that chaotic mixing [1], e.g. the exponential elongation of fluid elements by advection,...
Quantitatively estimating the permeability contribution of different pore structures in a heterogeneous porous medium plays a crucial role in assessing the influence of some diagenesis such as intragranular erosion and clay cement on the reservoir permeability. This study proposes an effective method to estimate the permeability contribution of a specific pore structure in a heterogeneous rock...
Geological storage of hydrogen (H2) and carbon dioxide (CO2) is pivotal for a successful energy transition toward a diversified low-carbon economy and a net-zero emission future. Wettability of reservoir rocks in the presence of formation fluids and H2 or CO2 is a controlling factor of gas mobility, residual trapping, and efficient storage. However, the influence of different brine types (salt...
The three major concerns of today’s society that relates to the energy sector are sustainability, security, and affordability for a growing population. Tackling the challenges that come along with that, requires a multiscale approach where modeling results incorporating the governing physics from the smallest scale can be translated into larger, more distinct scales to understand macroscopic...
RepoTREND ([1],[2]) is a new simulator designed to model the processes in a final repository for radioactive waste in different geological formations. RepoTREND provides functionalities for simulating the release of contaminants and their migration through the near-field and far-field to the biosphere, including the estimation of the radiological consequences for a human and the environment....
Energy transition and the current ambition of the geothermal industry requires the exploitation of currently used sedimentary aquifers in adjacent sites and the exploration of new reservoirs in distant locations or deeper underground layers. In new areas, physical, mechanical and thermal properties of rock are needed for correct reservoir characterization and implementing a geothermal project...
The capillary pressure defines the difference in pressure
between the non-wetting and wetting fluids. The capillary
pressure is part of the flow governing equations and its
definition can have a profound impact on the nature
of fluids displacement in a multiphase flow environment.
Conventionally, the capillary pressure - saturation relationships
are determined under equilibrium...
About 25% of the global population depends on karst groundwater. It is therefore essential to better understand the genesis and development of karst environments. Karst landscapes are shaped by multiple physical and chemical processes that occur over thousands to millions of years, the dominant one being the dissolution of soluble rocks like limestone or dolomite. This process strongly depends...
Aging is a key milestone of spirits production during which mass exchanges occur between brandies and the external environment. The barrel is a complex porous media made of oak wood and acting as a container [1]. During aging, the liquid present in a barrel partially impregnates the wood and migrates as liquid state. In the outer, non-impregnated part of the stave, vapour concentration...
When modeling multiphase fluid flows, the summation of the order parameters (or phase-field variables) is equal to unity. This order parameter equation can be used to reduce the number of flow equations by one. This reduction in the number of flow equations is always valid analytically. However, when it comes to numerical modeling, we observe that this reduction leads to different solution...
This study sets out to investigate the anisotropy of clay swelling by comparing the free swelling of specimens sampled radially and axially at different location in a large laboratory sedimented clay sample 20 x 6cm (diameter x height). The free swelling was measured on 2 x 2cm (diameter x height) cylindrical specimens sampled with stiff plastic containers having a closed based. The base had a...
Hydrogen is regarded as a key element of the energy transition, provided it is generated from renewables and/or decarbonized energies. Since this production is estimated to be intermittent as that of renewable electricity, safe storage of large quantities of H2 needs to be considered. Currently, hydrogen storages are operated in salt caverns. However, deep saline aquifers offer medium to very...
In recent years, water alternate emulsion injection (WAE) has been explored as a potential enhanced oil recovery method. Emulsion drops may block the pore throats diverting the aqueous phase towards oil-containing pores. The efficiency of the method strongly depends on the drop size distribution and interfacial properties of the emulsion. Emulsions are thermodynamically unstable systems and...
Several controlling mechanisms have been proposed to explain oil remobilization due to low-salinity effects. Among them, osmosis and water-in-oil emulsification have been widely reported as two potential mechanisms. However, our knowledge of these processes is limited, and their associated time scales are not well understood. To verify their roles, we have conducted a series of experiments in...
To tackle climate change and help smoother energy transition, Carbon Capture, Utilization and Storage (CCUS) technologies are seen as a primary line of defense. Storing carbon dioxide (CO2) in geological formations appears to be a feasible solution, yet there are many unknowns concerning the dynamics and safety of the storage. One of the important CO2 storage mechanisms is solubility trapping,...
Knowledge of electrolyte distribution inside Gas Diffusion Electrodes (GDE) is a key feature to improve the electrochemical behaviour of these electrodes. In processes like the chlor-alkali-electrolysis, a porous silver electrocatalyst is brought in contact with the liquid electrolyte and the gaseous reactants at the so-called three-phase boundary. To prevent flooding and to alter the...
Carbonate rocks are highly heterogeneous due to post-deposition physical and chemical changes. It exhibits various types of pores and a wide range of pore size distribution, making it challenging to capture all pores in a single pore geometry model obtained from imaging techniques used in Digital Rock Physics (DRP).
Digital rock analysis has proven to be promising and time efficient in...
Leakage along faults (pre-existing or reactivated) poses a major risk during CO2 storage. Faults and related structures such as micro cracks, joints, fracture networks, deformation bands, fault core etc., can either act as major structural traps or as a connecting pathway to shallow geological layers. Reservoir simulations with an accurate representation of fault-related properties across all...
The great challenge for understanding the porous media is the heterogeneity in rocks known as the core structures with different types and scales. Recently, with the development of digital core technology, more reliable information can be used to indicate the potential influence of fluid flowing in porous media. Thus, the pore-scale modeling that simulates the fluids flow directly in the...
The flow of sub-surface suspensions, and the controls on mobilisation, transport and deposition of a suspended load are important in natural (ground water migration, hydrocarbon migration, pollutant transport) and industrial (nuclear waste storage, CCS, hydrocarbon recovery) applications. In all of these areas we seek to understand how and when a suspended load moving through porous media will...
Microemulsions have been attracting great attention for their importance in various fields, including nanomaterial fabrication, food industry, drug delivery, and enhanced oil recovery. Atomistic insights into the self-microemulsifying process and the underlying mechanisms are crucial for the design and tuning of the size of microemulsion droplets toward applications. In this work,...
As the world continues to develop in a worsening climate crisis, greener alternatives to cement-based grouting must be implemented. Biological calcium carbonate precipitation methods such as Microbially Induced Carbonate Precipitation (MICP) show promise as alternative grouting strategies, but their biological nature lends itself to issues concerning environmental sensitivity and limited CaCO3...
Biobased materials have been applied more and more widely in the field of construction, thanks to their low thermal conductivity and humidity adsorption capacity. The application of them creates a promising way to lower resources assumption and carbon dioxide emission, contributing to sustainable development.
For better application of biobased construction materials, a full understanding of...
We consider a porous medium infiltrated by a reactive fluid that triggers coupled dissolution/precipitation reactions at pore surfaces. To study these processes, we model the porous medium as a system of interconnected pipes (Budek, 2012) with the diameter of each segment increasing in proportion to the local reactant consumption. With this model, we investigate different growth regimes in an...
The fundamental hydrologic processes that govern soil moisture dynamics in the vadose zone have a dominant effect on the transport and atmospheric loading of key greenhouse gases contributing to global climate change and related water issues worldwide. Drivers such as precipitation and heat and mass fluxes at the land surface impact vadose zone soil moisture distribution, which control the...
Highly performing Li-ion batteries are needed as part of reliable energy storage systems to successfully master the transition to renewable energies. To meet this challenge, batteries must be fast-charging, long-lasting, sustainable, and cost-effective to manufacture, while also offering high storage capacity. One essential piece of this highly challenging puzzle resides in improving the...
Image acquisition techniques are increasingly being employed for material characterization. For example, X-ray Mirco-Computed Tomography ($\mu$CT) can be seen in multiple works that study media such as reservoir rocks [2,3], and fibrous and woven materials [4,5], to cite a few. This sort of approach usually involves 3D numerical simulations at the microstructure, which is represented as a grid...
The optimal error estimate that depending only on the polynomial degree of ε^{-1} is established for the temporal semi-discrete scheme of the Cahn-Hilliard equation, which is based on the scalar auxiliary variable (SAV) formulation. The key to our analysis is to convert the structure of the SAV time-stepping scheme back to a form compatible with the original format of the Cahn-Hilliard...
Foam-assisted water-alternating-gas is a promising technology to control gas mobility in carbonate reservoirs. Maintaining the stability of the foam since its generation is key to achieve this goal. It has been widely demonstrated that the high water-solubility of the carbon dioxide (CO2) favors coarsening and coalescence phenomena, negatively affecting the stability of foams formed with this...
With the advent of climate change, a successful transition towards cleaner renewable energy calls for effective storage options. The utilization of underground energy storage (UES), such as depleted porous reservoirs, can help to overcome the balance between the production and demand of renewable energy. All underground energy storages, such as compressed air energy storage and hydrogen...
We establish a comprehensive description of the invading patterns formed when a wetting liquid displaces a non-wetting fluid in various porous mediums with geometric confinement variation. Building on model microfluidic experiments, we evidence imbibition scenarios yielding different imbibition stability and macroscopic morphologies controlled by geometric confinements and the capillary...
Bubble generation and transport play a role in many subsurface processes. Production and/or mobilization of gas is for instance observed in biogenic production of methane in peats, and in association with leakage from engineered geologic CO2 storage systems. Other subsurface engineered systems include in-situ air sparging in conjunction with soil vapor extraction, and electrical resistance...
In our poster we will present the complete toolchain for simulating the inertial fluid flow phenomena in pore-scale flows in two and three dimensions based on OpenFOAM (a popular, open–source finite volume code used in computational fluid dynamics).
Our work comprises of specialized python and bash scripts for automating the process of running simulations and post-processing the results. We...
Underground Hydrogen Storage (UHS), as an emerging large-scale energy storage technology with great compatibility with hydrogen economy, is at the centre of research attention in recent years. To investigate the feasibility of implementing UHS in porous reservoir such as aquifer or depleted hydrocarbon reservoirs, geochemical reactions brought by the presence of hydrogen in subsurface and...
The functionality of many electrochemical devices such as fuel cells, electrolysers or batteries rely on an electrically conductive porous media. Specifically, in Polymer Electrolyte Membrane (PEM) fuel cells, the gas diffusion layer (GDL) is used to distribute the gases, conduct the electrons and transport the generated water from the reaction sites to the flow fields in the bipolar plates...
Micromodels are 2D transparent model porous networks allowing for observations and quantification of numerous phenomena involved in fluid flow in porous media. In the context of energy studies, such as for CO2 storage or geothermal energy, micromodels are increasingly used. At the pore scale considered (i.e., roughly 10 - 100 μm for the micromodel), effects of surface and interfacial...
We set up a pore-scale model for reactive flow and transport in an evolving porous medium. We take into account dissolution/precipitation reactions of two competing minerals. The resulting space and time-dependent structural dynamics are included into the model by means of a level-set formulation.
We derive the corresponding effective model by formal two-scale
asymptotic expansion. This...
With the growing prevalence of renewable energy sources in innovative energy systems, interactions between energy supply and demand become more dynamic and complex. Therefore, along with the deployment of efficient and low-emission energy sources and sinks, energy storage is a central element of the energy transition. Especially for the case of thermal energy, a mismatch between high energy...
The characterisation and quantification of fractures are essential for the analysis of naturally or artificially fractured porous media. Moreover, fractures and faults can dominate flow across scales, from the reservoir to the core scale. Fractures often dominate flow at a larger scale, whilst, at the micro-scale, pore and micropore physics are highly important, and the fractures can act as a...
Hydrogen is considered to be a sustainable and clean energy carrier that holds significant potential to replace fossil fuels and hence enable an energy transition to meet the net-zero target set in the Paris Agreement in 2015. Large-scale underground hydrogen storage (UHS) in geological formations such as salt caverns, porous aquifers and depleted hydrogen reservoirs, can provide the predicted...
Objectives/Scope:
The oil industry produces large volumes of water along with the hydrocarbons (gas and oil), and in many cases the volumes of produced water exceeds the volume of water. Disposal of this contaminated water is a great challenge for the industry, however on fields where the wells are waterflooded with seawater an alternative disposal method is re-injecting the produced water....
eX-Poro-HydroDynamique lubrication (or XPHD lubrication) presents a different scientific approach to dealing with tribological problems. It’s an innovative inter- and multidisciplinary research topic which offers a promising sliding solution for various applications, such as bearings, thrust bearings, various guide components, etc. Its applications in both biological systems, and industrial...
Gas hydrates are nonstoichiometric crystalline compounds consisting of water and gas molecules, and can play a pivotal role in sustainable development. The formation process of gas hydrates, including nucleation and growth, is intrinsically affected by mineral surfaces and pore confinement in geological sediments. But the mechanisms underlying hydrate formation in confined spaces are not fully...
Currently, the industry standard for modelling Li-ion batteries at cell scale is known as “Porous Electrode Theory.” This approach has prevailed for about 50 years, and still undergirds the majority of commercial software and academic tools for this application. The macroscale equations employed in these models typically use a single tortuosity factor to estimate both effective diffusivity and...
The knowledge of pore size distribution and absolute permeability of porous media are key for a proper petrophysical characterization of a reservoir, which directly impacts the accuracy of hydrocarbon reserves estimation and the production strategies optimization. For the Oil and Gas exploration industry, downhole measurements are done to infer several properties and to perform a formation...
Carbon dioxide storage in subsurface formations is a promising technology for mitigating climate change, but a good understanding of the flow behaviour in targeted reservoirs is crucial. Heterogeneities at various scales can significantly impact flow behaviour, especially in carbonate reservoirs, which contain a large portion of the world's hydrocarbon reserves. In this study, we used an...
Carbonate reservoirs account for most of the global daily oil production and hold more than half of the world’s total proven conventional oil reserves. Surfactant flooding is one promising improved oil recovery technique to maintain production from mature carbonate reservoirs.
We apply three-dimensional pore-scale imaging and analysis at representative reservoir conditions to observe...
Interface between two phases, for instance two fluids as in viscous fingering, often grows in an unstable way. Fingers emerge from growing instability and compete for the available flux. This leads to effective repulsion between the fingers and screening of the shorter ones. While much interest was put into studying such systems before the interface reaches the boundary of the system, very...
To find the effective physical property of a rock, we need to upscale the property from the micro- to the macro-scale. In order to do this process in a correct manner, it is required to find a volume for which the homogenised property does not fluctuate anymore when the size of the sample is increased; the Representative Elementary Volume (REV). Its determination usually comes at the cost of a...
The phenomena of phase change and coexistence of two phases of a substance are of great interest in engineering. The two most widespread ways of describing these phenomena numerically are the sharp interface [1] and phase field [2] numerical models. The former assume that there is an abrupt transition at the interface between the two fluid phases while the latter propose a smooth transition...
Porosity is one of the main petrophysical inputs to any reservoir modelling technique, because it affects both the transport and storage properties of the rock. At the laboratory scale, digital rock models can be used to investigate the inner structure of the rock by applying non-invasive X-ray tomographic microscopy. In its most basic application, this approach enables identifying solid...
Carbon capture and storage (CCS) requires sealing caprocks to ensure the stored CO2 is contained in the reservoir and not leaking towards the surface. Many caprocks are composed of mudrocks, a siliciclastic sedimentary rock with a high clay content. We here analyse such a caprock from the Field S which is a potential CO2 storage site in the Sarawak Basin, East Malaysia. The determination of...
Inkjet printing inks frequently contain polar liquids of low volatility such as glycerol or poly(ethylene glycols) in addition to water as the main solvent. The deposition of these liquids on paper sheets induces swelling of the cellulose fibers, which leads to an overall, anisotropic deformation of the sheet. We characterized the corresponding strain components by means of a grid projection...
We have studied the imbibition and drying of water/co-solvent mixtures in paper and glass microfiber filters. The experiments reveal a rich interplay of solution imbibition, solvent evaporation and solvent-mediated pore-fiber transport. After deposition, liquids occupy the micron-scale inter-fiber pores of a paper sheet. In thermodynamic equilibrium, polar liquids such as water and co-solvents...
Viscous coupling during simultaneous flow of different fluid phases has a significant impact on their flow through porous media. In this work, a new multiscale strategy is proposed for multiphase flow in porous media. We use the interfacial continuum equation to simulate two-phase flow at pore scale and obtain empirical terms for the viscous coupling inside individual pores under variaous...
Additive Manufacturing techniques become increasingly important in the fabrication of geometrically complex structures. In particular, 3D-printing allows the production of curved and overhanging geometries, which are otherwise difficult to obtain. In order to produce membranes with this degree in freedom of design, this requires the development of inherently porous 3D-printable...
Sandstone and carbonate H2-wettability is an important factor that defines structural and residual trapping capacities and significantly influences multi-phase fluid dynamics in the rock. An increasing number of studies have evaluated this wettability by performing contact angle measurements on quartz and calcite; however, the reported data is fraught with uncertainty.
We show clearly that...
The production of heavy oil is challenging because of its higher viscosity and lower mobility. Although thermal-based methods are useful to cope with these problems through heat injection, the application of thermal recovery method are expensive and not always effective methods. Therefore, different alternatives were considered with respect to conditions of heavy oil reservoirs. Non-condensate...
Filtration is a well-researched industrial process in which solid particles are separated from a fluid by becoming trapped within the filter's internal structure. Recently, mathematical models have offered a cost-effective means to advance understanding of the filtration process and improve filtration performance. However, many models exhibit shortcomings which include large computational...
Mesoporous architectures in thin film configurations (< 10 μm) are promising class of materials for a range of applications, including antireflective coatings [1], electrochemical sensors [2], and electrode materials [3] among others. The low quantity of solid contained in such thin films makes their structural characterisation with conventional methods developed for bulk materials (e.g. N2...
With climate change mitigation actions in place, Carbon Capture and Storage (CCS) is by far the most industrially efficient technology to reach net-zero carbon emissions (HM Government, 2018), with current annual capture capacity exceeding 40 million tonnes of CO2 world-wide (BP, 2020). While supercritical CO2 is stored in conventional reservoirs or saline aquifers, overlying mudrock...
AFm phases of hydrous Ca-aluminates Ca2Al(OH)6·Cl·2H2O (also known as hydrocalumite) and Ca2Al(OH)6·I·2H2O were considered as adsorbent for radioactive anions. The layered structure of hydocalumite is formed by distorted Ca-hydroxide and Al-hydroxide octahedra. Its interlayers are formed by a highly ordered arrangement of Cl- anions and H2O molecules. It is structurally one of the best...
For gas storage in the geological reservoirs, it is important to understand fluid flow behaviour when capillary forces are dominant i.e. after the gas injection stops. In this work, we use numerical simulations to understand the capillary driven flow in layered porous reservoirs at Darcy scale. Using our model we want to predict if capillary breakthrough is possible in the cap rock based on...
As an alternative to water, supercritical carbon dioxide (CO2) has higher mobility and heat capacity to be used for heat extraction from geothermal reservoirs, while also trapping most of the injected CO2 underground to reduce carbon emissions and mitigate climate change. CO2 capture, utilization, and storage (CCUS) in geothermal reservoirs has become an attractive option for circular carbon...
In contrast to crystals, amorphous materials are characterized by a disordered structure that dictates adsorption at the surface. Understanding how amorphous features affect gas sorption is crucial to rationally design efficient amorphous adsorbents. Recently, we have demonstrated by Molecular Dynamics (MD) simulations the differences between the adsorption of CO$_2$ in crystalline (Fig 1a)...
The increasing need for hydrogen storage on a large scale has motivated new ideas on different methods of underground storage. Saline aquifers may offer a practical option for hydrogen storage due to their geographic availability and large capacity. However, reservoir engineering aspects of the injection and withdrawal of hydrogen in aquifers are yet to be understood. While 3D reservoir...
The water-based inks with polymeric latex particles used in printing technology deliver prints of superior quality at a low cost and environmental friendly. Via ink formulation and drying processes, the inkjet prints are characterized by a wide color gamut, intense gloss with tonal graduations and excellent mechanical properties.
Various methods and techniques are used to investigate the...
Deliquescence is the process by which a solid picks up water vapor from the atmosphere spontaneously and forms a solution. The deliquescence of a salt crystal is characterized by the deliquescence relative humidity (DRH) of the salt. Salt nanocrystals deliquesces differently than the bulk salt crystals. It has been shown in previous study that in comparison to the DRH of the bulk NaCl crystals...
Drilling operations required for recovery of deep geothermal energy are often challenging. This is due to the harsh downhole conditions encountered in geothermal wells, including high-pressure-and-high-temperature (HPHT) and the toughness of the rock found in many geothermal formations. Drilling in such environments requires special drilling fluid formulations that have high thermal stability,...
Instrinsic permeability of a porous material is a crucial material parameter in various application fields like e.g. geosciences, materials science and mechanical engineering. In these disciplines intrinsic permeability is a widley used input parameter for numerical simulations in the framework of continuum-scale models that employ Darcy’s law. However, the assumption of linearity in...
Chalk reservoirs are ubiquitous in the Danish north sea basin, making up to about 90% of the country’s historical hydrocarbon reserves. Oil and gas production from these fields peaked in 2005, and they are expected to be abandoned within the next 10 to 20 years. The existing knowledge of the basin accumulated during over 50 years of exploration and development allied with the existing...
Hydraulic fracturing is a widely used technique in shale oil and gas development. As a promising method, CO2 fracturing has been suggested because of various advantages, including lower formation sensitivity, lower fracturing pressure, and higher fracture intensity. However, the mechanisms are not well-understood. One of the potential reasons is the strong interaction between the fluids and...
As the world grapples with global warming and other environmental problems caused by the extensive use of fossil fuels, a rapid shift to renewable resources is essential. The intermittent nature of solar and wind energies, the two main renewable energy sources, is a bottleneck to the widespread use of these sustainable energies. Deployment of electrochemical energy devices might be a remedy...
Digital Rocks Portal (DRP, https://www.digitalrocksportal.org) organizes and preserves imaged datasets and experimental measurements of porous materials in subsurface, and beyond, with the mission to connect them to simulation and analysis, as well as educate the research community. We have over 150 projects represented in more than 200 publications, and an active community that reuses the...
Most of the Danish oil and gas is produced from Upper Cretaceous reservoirs, located in the North Sea. The rock is composed of chalk with some clay minerals as a minor impurity. Chalk is commonly considered tight, although it typically has high porosity. However, to adjust to the increasing demand for hydrocarbons, extraction of petroleum from less favorable reservoirs like the tight, high...
Two Phase flows are used in several fundamental and practical applications. For many applications, it is crucial to understand the physics of multiphase flow under the effect of the capillary, gravitational, and viscous fields [1]. Here, I will demonstrate experimentally how pore disorder affects fluid displacement. I am investigating the drainage of the liquid in porous media and studying the...
Soil temperature is a key parameter defining the coefficient of performance (CoP) for shallow burial ground source heat pumps (GSHP). Whilst many studies incorporate the effects of temperature attenuation due to conduction and temperature reduction due to evaporation, few studies incorporate the effects of latent heat of fusion associated with ice formation/thawing. This latter effect will be...
Foam is a promising means of increasing carbon storage in CO2 sequestration projects and waste isolation and removal in soil remediation, and a proven tool for enhanced oil recovery. Many of these applications involve fractured geological formations. Li et al. (2021a) studied inter-bubble diffusion and coarsening in foam in two glass model fractures. The bubbles were larger than the gap...
In this work, we discuss the effects of the electrical field on the mobilization and the transportation of contaminants through porous media. In this type of process, various interactive electro-physico-chemical phenomena can occur, which makes it difficult to capture all of the process contribution (complexity) in a model. Therefore, the already existing models do not attempt to simulate...
Aquifer systems represent the major source for mankind’s drinking and irrigation water demands. Throughout the past two decades, they have also increasingly got into focus for geothermal energy usage. The protection of groundwater against detrimental impacts is essential to prevent or minimize risks associated with contamination, water scarcity, and to ensure a sustainable transition towards...
Multiphase flow and reactive transport in porous media play a key role in various applications needed for establishing hydrogen as an alternative energy carrier. The porous media facilitating the hydrogen flow in presence of another fluid needs to be optimized in terms of reactivity and transport properties. Two important parameters controlling reactivity and multiphase flow transport in a...
Understanding two-phase flow in porous media is highly significant in many fields of science and engineering in terms of both theory and practice. Fundamentally, pore-scale immiscible displacement is governed by the wettability of the pore-wall, which in turn, influences the distribution and transport of the fluid phases at the micro- to macro-scale. Whilst two-phase transport mechanisms in...
The disintegration process of pharmaceutical solid dosage forms refers to a mechanical break-up of an intact tablet into smaller fragments to enhance the drug substance’s contact with the dissolution medium. This process is particularly critical for immediate-release dosage forms to ensure the end product’s bioavailability and efficacy. Despite the significance of disintegration, the...
Light-non-aqueous phase liquids (LNAPLs) are important sources of soil contamination worldwide. Significant fluctuations of the soil bio/geochemical properties (metabolisms types, redox) and significant spatial-temporal variations of the pollutant saturation distribution occur on the LNAPL different phases (pure phase, dissolved, residual, entrapped droplets). These fluctuations are often...
Volumetric water vapour sorption isotherms have been carried out in nanoporous monolithic glass membranes (Vycor) in both empty and salt solution (Li-/NaCl) filled pores in order to investigate the relative humidity and pore-filling fraction associated with capillary condensation and peak desorption/desorption-tension, and the impact of salt solution activity/chemical nature on such processes....
The cleaning and decontamination of various porous surfaces (e.g., concrete, tarmac, wood, etc.) is a challenging and multidisciplinary problem for both fundamental understanding and a wide range of industrial, medical, urban, everyday-life and disaster-response applications [1]. The role of such processes is particularly crucial in cases where contaminants (such as chemical substances and...
Traditional mineral investigation techniques are normally destructive and although they provide very useful information, they come with disadvantages and limitations some of which cannot be ignored. A case in point is the mechanical damage in the preparation process of SEM scanning during which artifacts will be introduced to the results. Micro-computed tomography (µCT) in combination with...
We study imbibition and drainage through a localised constriction in a Hele-Shaw cell, as a model system designed to gain insight into multiphase displacements in porous media. In this context, the detailed quantitative response of the non-local interface dynamics to localised defects at nonzero flow rate is a key feature that remains poorly understood. Combining experiments, numerical...
Multiphase fluid flow through porous media has many beneficial applications for various industries such as oil and gas, hydrology, geothermal, medical, and manufacturing. A substantial amount of research has been carried out at various scales (e.g., reservoir, Darcy, microscale) to further understand the fluid behavior, with many recent studies directed towards the pore scale. This work has...
Self-assembly phenomena have been observed widely in the interface of multi-phase flow in porous media. Surfactant or surfactant-like particles play an important role during the self-assembly process. In this work, we employed a series of molecular dynamics simulations to investigate the self-micro emulsification and formation of self-assembly nanoparticle film. Atomistic insights into the...
Drainage, imbibition and steady state two phase flow in porous media have an abundance of applications in physics, chemistry and engineering. Experimental methods to capture this phenomena are often limited to two dimensional setups, refractive index matching and/or are too slow to capture the dynamics at a resolution relevant to the physics at the pore scale. We utilize nuclear magnetic...
A numerical model is developed to simulate the drainage process of porous pavements. The aim of this work is to gain a deeper understanding of the underlying processes and the relevant influencing parameters.
Porous pavements, such as porous asphalt (PA), are characterised by their high void content and are increasingly used in Germany and many other countries on highly congested roads...
In a full-scale CCS, millions of tons of CO2 must be stored underground. Injection of dry or undersaturated (with respect to water) CO2 leads to dry-out of the brine formation water and salt precipitation, particularly in the near wellbore region, causing reduced injectivity and deteriorated reservoir rock properties. We report a series of microfluidic experiments on glass- and geomaterial...
The CO2 dissolution in the reservoir brine (eg. within an aquifer) is one of the primary trapping mechanisms during CO2 geological storage (CGS). Significant amounts of injected CO2 can be trapped in this way with the overall dissolution rate controlled by density-driven convective mixing (CM). As such, the CO2 solutal convection results from the gravitational instability: under the action of...
Material failure and fracture growth are phenomena that without a doubt have significant impact on industry and society alike. They dictate how long structures will last and what loads they can withstand, critical topics to consider in any engineering project. While some analytical formulations have shown partial success in describing and predicting material failure, numerical studies of Fiber...
Structure and transport of n-pentane and n-dodecane in clay nanopores are investigated using molecular dynamics (MD) method. OPLS-AA/CM1A force field [1] is used for hydrocarbons and ClayFF force field [2] is used to simulate pyrophyllite and montmorillonite pore walls.
The viscosity of hydrocarbons and slip lengths against the pore walls are calculated using non-equilibrium MD simulations of...
Natural gas hydrate is a type of potential clean energy resource with vast reserves concentrated in the permafrost and submarine deposits as a solid phase. During the hydrate exploitation process, the hydrate transforms from a solid phase to the gas and water phases and flows in the porous media. Particle movement occurs in the pore space due to the hydrate phase transition, leading to the...
Capillary rise dynamics of molecular liquids in nanoporous solid is governed by the interplay of liquid’s viscosity, the liquid-solid interaction and permeability of the porous medium. Classical hydrodynamics provides a square-root-of-time dependent law to describe the liquid front advancement during imbibition, also known as Lucas-Washburn law (L-W). Although the validity of the L-W law down...
