Quantitative Analysis for the Reconstruction of Porous Media Using Multiple-Point Statistics

The pore structure reconstruction of the porous media is of great importance to the research of mechanisms of fluid flow in porous media. To capture the large-scale patterns in the pore space, the multiple-point statistical technique is generally adopted for porous media reconstruction. Commonly, two different schemes, i.e., the single-grid scheme and the multiple-grid scheme, can be applied for simulation realization. The selection between this two schemes and a proper data template size have thus become a new research issue, and the performance of the characteristic reproduction of the training image using this two schemes must be quantified. In this paper, a series of multiple-point statistics simulation basing on a 2D micro-CT sandstone image are proceeded using both single- and multiple-grid schemes, and different data templates are adapted for porous media reconstruction. Further, to quantify the impact of the computational schemes and setting of the data template to the simulation realizations, a number of measurements considering the pore diameter, porosity, connectivity, and permeability are implemented to fully analyze the results obtained. Results show that by using the single-point statistical method, a large template is necessary to reproduce large-scale structures. The multiple-grid template method may bring great benefits to simulation efficiency over the simple data template method, as well as the recovery of the pore long-range geometric features and seepage characteristics. With the extension of the template for the multiple-grid scheme, the simulation results show lack of variations to some extent.

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The MPS Reconstruction of Porous Media Using Multiple-Grid Templates

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.462-463.462 ◽

2013 ◽

Vol 462-463 ◽

pp. 462-465 ◽

Cited By ~ 1

Author(s):

Yi Du ◽

Ting Zhang

Keyword(s):

Porous Media ◽

Large Scale ◽

Grid Method ◽

Training Image ◽

Multiple Point ◽

Grid Data ◽

Large Scale Structures ◽

Complex Features ◽

Grid Nodes ◽

Data Template

It is difficult to reconstruct the unknown information only by some sparse known data in the reconstruction of porous media. Multiple-point geostatistics (MPS) has been proved to be a powerful tool to capture curvilinear structures or complex features in training images. One solution to capture large-scale structures while considering a data template with a reasonably small number of grid nodes is provided by the multiple-grid method. This method consists in scanning a training image using increasingly finer multiple-grid data templates instead of a big and dense data template. The experimental results demonstrate that multiple-grid data templates and MPS are practical in porous media reconstruction.

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Influence of pore geometry on motility and trapping of metal reducing bacteria

10.5194/egusphere-egu2020-4226 ◽

2020 ◽

Author(s):

Lazaro J. Perez ◽

Nicole L. Sund ◽

Rishi Parashar ◽

Andrew E. Plymale ◽

Dehong Hu ◽

...

Keyword(s):

Porous Medium ◽

Porous Media ◽

Large Scale ◽

Ad Hoc ◽

Pore Space ◽

Practical Applications ◽

Bacterial Migration ◽

Reducing Bacteria ◽

The Impact ◽

Metal Reducing Bacteria

Diverse processes such as bioremediation, biofertilization, and microbial drug delivery rely on bacterial migration in porous media. However, how pore-scale confinement alters bacterial motility is unknown due to the inherent heterogeneity in porous media. As a result, models of migration are limited and often employ ad hoc assumptions. We aim to determine the impact of pore confinement in the spreading dynamics of two populations of motile metal reducing bacteria by directly visualizing individual Acidovorax and Pelosinus in an unconfined liquid medium and in a microfluidic chip containing regular placed pillars. We observe that the length of runs of the two species differs from the unconfined and confined medium. Results show that bacteria in the confined medium display a systematic shorter jumps due to grain obstacles when compared to the open porous medium. Close inspection of the trajectories reveals that cells are intermittently and transiently trapped, which produces superdiffusive motion at early and subdiffusion behavior at late times, as they navigate through the confined pore space. While in the open medium, we observe a linearly increasing variance with respect to time for Acidovorax, and for Pelosinus the variance increases at a much faster rate showing super diffusive behavior at early times. At late times, the rate of growth in spreading increases for Acidovorax while it reduces for Pelosinus. We finally discuss that the paradigm of run-and-tumble motility is dramatically altered in the confined porous medium and its practical applications of these effects on large-scale transport.

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Experimental Study of Natural Ions and Rock Interactions for Seawater Breakthrough Percentage Monitoring during Offshore Seawater Flooding

SPE Journal ◽

10.2118/201553-pa ◽

2021 ◽

pp. 1-21

Author(s):

Yanqing Wang ◽

Xiang Li ◽

Jun Lu

Keyword(s):

Porous Media ◽

Fluid Flow ◽

Barium Sulfate ◽

Large Deviation ◽

Exchange Process ◽

Reaction Model ◽

Sodium Content ◽

Flow In Porous Media ◽

Formation Water ◽

The Impact

Summary Seawater breakthrough percentage monitoring is critical for offshore oil reservoirs because seawater fraction is an important parameter for estimating the severity of many flow assurance issues caused by seawater injection and further developing effective strategies to mitigate the impact of those issues on production. The validation of using natural ions as a tracer to calculate the seawater fraction was investigated systematically by studying the natural chemical composition evolution in porous media using coreflood tests and static bottle tests. The applicable range of ions was discussed based on the interaction between ion and rock. The barium sulfate reactive model was improved by integrating interaction between ions and rock as well as fluid flow effect. The results indicate that chloride and sodium interact with rock, but the influence of the interaction can be minimized to a negligible level because of the high concentrations of chloride and sodium. Thus, chloride and sodium can be used as conservative tracers during the seawater flooding process. However, adsorption/desorption may have a large influence on chloride and sodium concentrations under the scenario that both injection water and formation water have low chloride and sodium content. Bromide shows negligible interaction with rock even at low concentrations and can be regarded as being conservative. The application of a barium and sulfate reaction model in coreflood tests does not work as well as in bottle tests because fluid flow in porous media and ion interaction with rock is not taken into account. Although sulfate and barium adsorption on clay is small, it should not be neglected. The barium sulfate reaction model was improved based on the simulation of ion transport in porous media. Cations (magnesium, calcium, and potassium) are involved in the complicated cation-exchange process, which causes large deviation. Therefore, magnesium, calcium, and potassium are not recommended to calculate seawater fraction. Boron, which exists as anions in formation water and is used as a conservative tracer, has significant interactions with core matrix, and using boron in an ion tracking method directly can significantly underestimate the seawater fraction. The results give guidelines on selecting suitable ions as tracers to determine seawater breakthrough percentages under different production scenarios.

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Pore-scale Mixing and the Evolution from Anomalous to Normal Hydrodynamic Dispersion

10.5194/egusphere-egu21-13655 ◽

2021 ◽

Author(s):

Marco Dentz ◽

Alexandre Puyguiraud ◽

Philippe Gouze

Keyword(s):

Porous Media ◽

Large Scale ◽

Molecular Diffusion ◽

Pore Space ◽

Breakthrough Curves ◽

Heterogeneous Porous Media ◽

Hydrodynamic Dispersion ◽

Pore Scale ◽

Sandstone Sample ◽

Flow Variability

Transport of dissolved substances through porous media is determined by the complexity of the pore space and diffusive mass transfer within and between pores. The interplay of diffusive pore-scale mixing and spatial flow variability are key for the understanding of transport and reaction phenomena in porous media. We study the interplay of pore-scale mixing and network-scale advection through heterogeneous porous media, and its role for the evolution and asymptotic behavior of hydrodynamic dispersion. In a Lagrangian framework, we identify three fundamental mechanisms of pore-scale mixing that determine large scale particle motion: (i) The smoothing of intra-pore velocity contrasts, (ii) the increase of the tortuosity of particle paths, and (iii) the setting of a maximum time for particle transitions. Based on these mechanisms, we derive an upscaled approach that predicts anomalous and normal hydrodynamic dispersion based on the characteristic pore length, Eulerian velocity distribution and P&#233;clet number. The theoretical developments are supported and validated by direct numerical flow and transport simulations in a three-dimensional digitized Berea sandstone sample obtained using X-Ray microtomography. Solute breakthrough curves, are characterized by an intermediate power-law behavior and exponential cut-off, which reflect pore-scale velocity variability and intra-pore solute mixing. Similarly, dispersion evolves from molecular diffusion at early times to asymptotic hydrodynamics dispersion via an intermediate superdiffusive regime. The theory captures the full evolution form anomalous to normal transport behavior at different P&#233;clet numbers as well as the P&#233;clet-dependence of asymptotic dispersion. It sheds light on hydrodynamic dispersion behaviors as a consequence of the interaction between pore-scale mixing and Eulerian flow variability.&#160;

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Reconstruction of 3D Porous Media Using Multiple-Point Statistics Based on a 2D Training Image

10.2118/190859-ms ◽

2018 ◽

Author(s):

Yuqi Wu ◽

Chengyan Lin ◽

Lihua Ren ◽

Weichao Tian ◽

Yang Wang ◽

...

Keyword(s):

Porous Media ◽

Training Image ◽

Multiple Point ◽

Multiple Point Statistics

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Reconstruction of 3D porous media using multiple-point statistics based on a 3D training image

Journal of Natural Gas Science and Engineering ◽

10.1016/j.jngse.2017.12.032 ◽

2018 ◽

Vol 51 ◽

pp. 129-140 ◽

Cited By ~ 16

Author(s):

Yuqi Wu ◽

Chengyan Lin ◽

Lihua Ren ◽

Weichao Yan ◽

Senyou An ◽

...

Keyword(s):

Porous Media ◽

Training Image ◽

Multiple Point ◽

Multiple Point Statistics

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Influence of heterogeneous air entry pressure on large scale unsaturated flow in porous media

Acta Geophysica ◽

10.2478/s11600-014-0224-7 ◽

2014 ◽

Vol 62 (5) ◽

pp. 1179-1191 ◽

Cited By ~ 4

Author(s):

Adam Szymkiewicz ◽

Insa Neuweiler ◽

Rainer Helmig

Keyword(s):

Porous Media ◽

Large Scale ◽

Unsaturated Flow ◽

Flow In Porous Media ◽

Entry Pressure

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A multiple-point statistics algorithm for 3D pore space reconstruction from 2D images

Advances in Water Resources ◽

10.1016/j.advwatres.2011.06.003 ◽

2011 ◽

Vol 34 (10) ◽

pp. 1256-1267 ◽

Cited By ~ 86

Author(s):

Alireza Hajizadeh ◽

Aliakbar Safekordi ◽

Farhad A. Farhadpour

Keyword(s):

Pore Space ◽

Multiple Point ◽

Multiple Point Statistics ◽

2D Images

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POD-Galerkin Model for Incompressible Single-Phase Flow in Porous Media

Open Physics ◽

10.1515/phys-2016-0061 ◽

2016 ◽

Vol 14 (1) ◽

pp. 588-601 ◽

Cited By ~ 4

Author(s):

Yi Wang ◽

Bo Yu ◽

Shuyu Sun

Keyword(s):

Porous Media ◽

Large Scale ◽

Single Phase ◽

Galerkin Projection ◽

Flow In Porous Media ◽

Computational Time ◽

Speed Up ◽

Fast Prediction ◽

Proper Orthogonal ◽

Phase Fluid

AbstractFast prediction modeling via proper orthogonal decomposition method combined with Galerkin projection is applied to incompressible single-phase fluid flow in porous media. Cases for different configurations of porous media, boundary conditions and problem scales are designed to examine the fidelity and robustness of the model. High precision (relative deviation 1.0 × 10−4% ~ 2.3 × 10−1%) and large acceleration (speed-up 880 ~ 98454 times) of POD model are found in these cases. Moreover, the computational time of POD model is quite insensitive to the complexity of problems. These results indicate POD model is especially suitable for large-scale complex problems in engineering.

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