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View article: Numerical Investigation of Preferential Flow Paths in Enzymatically Induced Calcite Precipitation Supported by Bayesian Model Analysis
Numerical Investigation of Preferential Flow Paths in Enzymatically Induced Calcite Precipitation Supported by Bayesian Model Analysis Open
The usability of enzymatically induced calcium carbonate precipitation (EICP) as a method for altering porous media properties, soil stabilization, or biocementation depends on our ability to predict the spatial distribution of the precipi…
View article: A numerical 1D reactive flow and transport model for cementation processes in bio-concrete production
A numerical 1D reactive flow and transport model for cementation processes in bio-concrete production Open
Concrete is the most widely used construction material globally, with Portland-cement production contributing 8% to global CO2 emissions. Developing alternative cementation processes is therefore crucial for reducing these emissions. One p…
View article: Modelling contaminant transport of soil and landfills: A benchmark study of three numerical Codes
Modelling contaminant transport of soil and landfills: A benchmark study of three numerical Codes Open
Nuclear waste that is not deposited in a repository must pass through officially approved clearance procedures, which are regulated in the German Radiation Protection Ordinance (StrlSchV 2024). After clearance, the materials can be fed int…
View article: Benchmarking CO$_2$ Storage Simulations: Results from the 11th Society of Petroleum Engineers Comparative Solution Project
Benchmarking CO$_2$ Storage Simulations: Results from the 11th Society of Petroleum Engineers Comparative Solution Project Open
The 11th Society of Petroleum Engineers Comparative Solution Project (shortened SPE11 herein) benchmarked simulation tools for geological carbon dioxide (CO$_2$) storage. A total of 45 groups from leading research institutions and industry…
View article: Hydro-Geomechanical Porous-Media Model to Study Effects of Engineered Carbonate Precipitation in Faults
Hydro-Geomechanical Porous-Media Model to Study Effects of Engineered Carbonate Precipitation in Faults Open
Hydro-geomechanical models are required to predict or understand the impact of subsurface engineering applications such as gas storage in geological formations. This study focuses on engineered carbonate precipitation through biomineraliza…
View article: A hydro-geomechanical porous-media model to study effects of engineered carbonate precipitation in faults
A hydro-geomechanical porous-media model to study effects of engineered carbonate precipitation in faults Open
Hydro-geomechanical models are required to predict or understand the impact of subsurface engineering applications as, for example, in gas storage in geological formations. This study puts a focus on engineered carbonate precipitation thro…
View article: Intermittent flow paths in biofilms grown in a microfluidic channel
Intermittent flow paths in biofilms grown in a microfluidic channel Open
Biofilms exposed to flow experience shear stress, which leads to a competitive interaction between the growth and development of a biofilm and shearing. In this study, Pseudonomas fluorescene biofilm was grown in a microfluidic channel and…
View article: Measuring carbonate dissolution rates under well-controlled conditions for reactive CO2-water flow in a large lab-scale karst fracture imitate
Measuring carbonate dissolution rates under well-controlled conditions for reactive CO2-water flow in a large lab-scale karst fracture imitate Open
This study explores the carbonate dissolution dynamics in karstic systems by simulating reactive water flow under controlled large lab-scale laboratory conditions. Using a 1 m² Jura limestone tile, the experiments focus on carbonate dissol…
View article: A hydro-geomechanical porous-media model tostudy effects of engineered carbonateprecipitation in faults
A hydro-geomechanical porous-media model tostudy effects of engineered carbonateprecipitation in faults Open
Subsurface engineering applications, such as CO2 storage, face critical challenges related to safety and sustainability, including induced seismicity and potential leakage pathways, particularly in fault zones. Biomineralization, specifica…
View article:   Large Temperatures in Water Distribution Pipes as a Water Quality Threat: Measurements and Modelling
  Large Temperatures in Water Distribution Pipes as a Water Quality Threat: Measurements and Modelling Open
Due to climate change, new challenges arise in drinking water infrastructure planning and in the re-assessment of well-established urban drinking water utilities. We observed temperatures exceeding 25 °C in drinking water supply pipes…
View article: Efficient Approximation of Initial Conditions for Global Sensitivity Analysis and History Matching of Transient Numerical Groundwater Models
Efficient Approximation of Initial Conditions for Global Sensitivity Analysis and History Matching of Transient Numerical Groundwater Models Open
Numerical groundwater models are essential tools for simulating and understanding subsurface hydrological processes, supporting water resource management and environmental decision-making. Global sensitivity analysis (GSA) and history matc…
View article: Intermittent flow paths in biofilms grown in a microfluidic channel
Intermittent flow paths in biofilms grown in a microfluidic channel Open
Biofilms, complex microbial communities embedded in an extracellular matrix, are significantly influenced by flow-induced shear stress, which creates a competition between biofilm growth and detachment. In this study, biofilms of Pseudomon…
View article: Rayleigh Invariance Allows the Estimation of Effective CO<sub>2</sub> Fluxes Due To Convective Dissolution Into Water‐Filled Fractures
Rayleigh Invariance Allows the Estimation of Effective CO<sub>2</sub> Fluxes Due To Convective Dissolution Into Water‐Filled Fractures Open
Convective dissolution of is a well‐known mechanism in geological storage of . It is triggered by gravitational instability which leads to the onset of free convection. The phenomenon is well studied in porous media, such as saline aquifer…
View article: Implementation Pitfalls for Carbonate Mineral Dissolution -- a Technical Note
Implementation Pitfalls for Carbonate Mineral Dissolution -- a Technical Note Open
In systems with slow reaction kinetics, such as mineral dissolution processes, chemical equilibrium cannot be assumed and an accurate understanding of reaction rates is essential; discrepancies in parameter reporting can greatly affect sim…
View article: Rayleigh invariance allows the estimation of effective CO2 fluxes due to convective dissolution into water-filled fractures
Rayleigh invariance allows the estimation of effective CO2 fluxes due to convective dissolution into water-filled fractures Open
Convective dissolution of CO2 is a well-known mechanism in geological storage of CO2 . It is triggered by gravitational instability which leads to the onset of free convection. The phenomenon is well studied in porous media, such as saline…
View article: Comparing Different Coupling and Modeling Strategies in Hydromechanical Models for Slope Stability Assessment
Comparing Different Coupling and Modeling Strategies in Hydromechanical Models for Slope Stability Assessment Open
The dynamic interaction between subsurface flow and soil mechanics is often simplified in the stability assessment of variably saturated landslide-prone hillslopes. The aim of this study is to analyze the impact of conventional simplificat…
View article: Estimation of Capillary‐Associated NAPL‐Water Interfacial Areas for Unconsolidated Porous Media by Kinetic Interface Sensitive (KIS) Tracer Method
Estimation of Capillary‐Associated NAPL‐Water Interfacial Areas for Unconsolidated Porous Media by Kinetic Interface Sensitive (KIS) Tracer Method Open
By employing kinetic interface sensitive (KIS) tracers, we investigate three different types of glass‐bead materials and three natural porous media systems to quantitatively characterize the influence of the porous‐medium grain‐, pore‐size…
View article: Heat transport from atmosphere through the subsurface to drinking‐water supply pipes
Heat transport from atmosphere through the subsurface to drinking‐water supply pipes Open
Drinking‐water quality in supply pipe networks can be negatively affected by high temperatures during hot summer months due to detrimental bacteria encountering ideal conditions for growth. Thus, water suppliers are interested in estimatin…
View article: The FluidFlower Validation Benchmark Study for the Storage of CO$$_2$$
The FluidFlower Validation Benchmark Study for the Storage of CO$$_2$$ Open
Successful deployment of geological carbon storage (GCS) requires an extensive use of reservoir simulators for screening, ranking and optimization of storage sites. However, the time scales of GCS are such that no sufficient long-term data…
View article: Dynamics of seasonal CO2 concentrations above and below the karst-water table are influenced by density-driven transport: monitoring data from a cave in the Swabian Jura and interpretation with numerical simulation models
Dynamics of seasonal CO2 concentrations above and below the karst-water table are influenced by density-driven transport: monitoring data from a cave in the Swabian Jura and interpretation with numerical simulation models Open
It is long known that dissolved aqueous CO2 is the key driving force of chemical reactions leading to rock corrosion, which is denoted as karstification. Accordingly, it is evident that meteoric water percolating through the biologically a…
View article: The FluidFlower International Benchmark Study: Process, Modeling Results, and Comparison to Experimental Data
The FluidFlower International Benchmark Study: Process, Modeling Results, and Comparison to Experimental Data Open
Successful deployment of geological carbon storage (GCS) requires an extensive use of reservoir simulators for screening, ranking and optimization of storage sites. However, the time scales of GCS are such that no sufficient long-term data…
View article: Seasonal Dynamics of Gaseous CO2 Concentrations in a Karst Cave Correspond with Aqueous Concentrations in a Stagnant Water Column
Seasonal Dynamics of Gaseous CO2 Concentrations in a Karst Cave Correspond with Aqueous Concentrations in a Stagnant Water Column Open
Dissolved CO2 in karst water is the key driving force of karstification. Replenishment of CO2 concentrations in karst water occurs by meteoric water that percolates through the vadose zone, where CO2 produced from microbial activity is dis…
View article: Spatiotemporal Distribution of Precipitates and Mineral Phase Transition During Biomineralization Affect Porosity–Permeability Relationships
Spatiotemporal Distribution of Precipitates and Mineral Phase Transition During Biomineralization Affect Porosity–Permeability Relationships Open
Enzymatically induced calcium carbonate precipitation is a promising geotechnique with the potential, for example, to seal leakage pathways in the subsurface or to stabilize soils. Precipitation of calcium carbonate in a porous medium redu…