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This sheet provides data from three-phase Ostwald ripening simulation results for gas bubble in a 2D homogeneous porous medium. In this workbook, we use 'O' and 'W' to refer to oil and water phase. Sheet names for three phase simulation results have the format: sim__ _. Here, X and Y are placeholders for 'O' and 'W'. The sequence of 'O' and 'W' in the sheet name reflects which phase is on the left and which is on the right side in the geometry. P is a placeholder for oil-water capillary pressure. N is placeholder for bubble size distribution. So, two sheets with same 'N' have the same bubble size distribution. The gas bubbles can be in contact with oil, water, or both oil and water. The column headings can be understood as follows: 1. P - Pressure of bubble - average pressure of bubbles in the system 2. Vol - Volume of a bubble 3. _O - Bubble is surrounded by oil 4. _W - Bubble is surrounded by water 5. _OW - Bubble is surrounded by oil and water 6. _{1-9} - The digit at the end is number of the bubble having similar gas-liquid interface Sheet names for three phase analytical results have the format: Ana_ . Here, P is a placeholder for oil-water capillary pressure. Time is in seconds, pressure is in Pascals, and volume is in 10-9 m2. The data corresponds to the paper: "Pore-scale Ostwald ripening of gas bubbles in the presence of oil and water in porous media", and the sheet names reflect the section number of the article. For further details of the model and simulations, refer to the published article in 'Journal of Colloid and Interface Science'.

We couple a free solute diffusion model to a model of crystal surface growth represented by, but not limited to, a (2 + 1)-dimensional solid-on-solid (SOS) model confined by a flat surface. We use kinetic Monte Carlo (KMC) with dissolution rates based on nearest-neighbor interactions to solve the Master equation for the surface dynamics, and we use an offlattice random walk to model the Fickian diffusion of the solute particles. The two solvers are coupled directly through deposition rates of the free particles calculated using the mean first passage time (MFPT) of deposition that is found to scale as $r^{-4}$. Two variants are studied: ignoring (radial) and not ignoring the line of sight (pathfinding). Reference models such as uniform concentration (random deposition) and lattice diffusion (crystal lattice extended into the liquid) are used for comparison. We find that the macroscopic limit of the surface dynamics is reproduced by all models. The free diffusion models produce a lower equilibrium roughness and a smaller height autocorrelation length than the reference models, and are found to behave very well in tight confinements. It is also demonstrated that lattice diffusion does not work well in tight confinements. The two MFPT models behave very similarly close to equilibrium and for dissolution, but becomes increasingly different with increasing surface growth speed. The model is put to use by simulating a cavity with a flux boundary condition at one side. The conclusion is that the new model excels in confinement, and line of sight can in practice be ignored since the dominant deposition sites likely are in line of sight, which minimizes the CPU-time needed in the coupling., 13 pages, 9 figures

Faults, landslides and subglacial till often contain accumulations of granular debris. Their macroscopic motion is at least to some extent determined by the processes operating in this sheared granular material. A valid question in these environments is how the local behaviour at the individual granular contacts actually sums up to influence macroscopic sliding. Laboratory experiments and numerical modelling can potentially help elucidate this. Observations of jamming and unjamming as well as concentrated shear bands that appear to scale with grain size, suggest that a simple continuum description may be insufficient to capture important elements of the behaviour. We therefore seek a measure of the organisation of the granular fabric and the structure of the load bearing skeleton that shows how the individual grain interactions are summing up to influence the macroscopic sliding behaviour we observe. Contact force networks are an expression of this. We choose to investigate variability of the ‘important’ or most connected system spanning strong force networks produced in 3D discrete element models of granular layers under shear. We use percolation measures to identify, compare and track the evolution of these system spanning contact force networks. We show that the geometries and interactions of these load bearing structures, reflected as specific topological measures, are sensitive to size (and likely shape) distribution of the granular material. Importantly, distinct (measurable) changes in the topological structural characteristics of strong force networks with accumulated strain are directly correlated to fluctuations in macroscopic shearing resistance. This illustrates the sensitivity of 3D force networks to details of granular materials (such as size and shape distribution) and also the important bridging role they play between individual grain scale processes and macroscopic sliding behaviour.

Pore-scale imaging of two-phase flow in porous media shows that pore filling occurs as cooperative events with accompanying spontaneous fluid redistribution in other parts of the pore space. We present a level set method that controls saturation quasi-statically to model experiments controlled by low, constant flow rates and demonstrate that our method can describe the observed displacement mechanisms. The level set approach determines states of capillary equilibrium, which generally are different for displacement protocols constrained by saturation and pressure. Saturation-controlled simulations of drainage in sandstone show spontaneous fluid redistributions with abrupt pressure jumps and cooperative behavior, including snap-off and interface retraction events, consistent with experimental observations. Drainage capillary pressure curves are lower when saturation, rather than pressure, controls displacement. Remarkably, these effects are less significant for imbibition processes where the development of hydraulically connected wetting phase moderates the cooperative behavior and associated pressure jumps.