Trapping patterns during capillary displacements in disordered media

2022 ◽  
Vol 933 ◽  
Author(s):  
Fanli Liu ◽  
Moran Wang
Keyword(s):  
Numerical Simulations ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Disordered Media ◽  
Pore Geometry ◽  
Control Parameters ◽  
Pore Throat ◽  
The Impact ◽  
Theoretical Analyses

We investigate the impact of wettability distribution, pore size distribution and pore geometry on the statistical behaviour of trapping in pore-throat networks during capillary displacement. Through theoretical analyses and numerical simulations, we propose and prove that the trapping patterns, defined as the percentage and distribution of trapped elements, are determined by four dimensionless control parameters. The range of all possible trapping patterns and how the patterns are dependent on the four parameters are obtained. The results help us to understand the impact of wettability and structure on trapping behaviour in disordered media.

RELIABLE QUANTIFICATION OF PORE GEOMETRY IN CARBONATE ROCKS USING NMR AND ELECTRICAL RESISTIVITY MEASUREMENTS FOR ENHANCED ASSESSMENT OF PERMEABILITY AND CAPILLARY PRESSURE

2021 ◽  
Author(s):  
Zulkuf Azizoglu ◽  
◽  
Artur Posenato Garcia ◽  
Zoya Heidari ◽  
◽  
...  
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Capillary Pressure ◽  
Size Distribution ◽  
Pore Geometry ◽  
Pore Throat ◽  
Permeability Model ◽  
Resistivity Measurements ◽  
Constriction Factor ◽  
Directional Permeability

Reliable and real-time assessment of directional permeability and saturation-dependent capillary pressure are utterly important because they significantly affect the exploitation strategies. Conventional well-log-based methods (e.g., NMR-based, saturation-height analysis, resistivity-based, correlation-based) are either highly dependent on calibration efforts or rely on model parameters which are difficult to obtain in real-time and make them dependent on core measurements. Moreover, most conventional methods for assessment of directional permeability and saturation-dependent capillary pressure fail in the presence of multi-modal pore-size distribution. Recent publications suggested that integration of transverse Nuclear Magnetic Resonance (T2 NMR) and resistivity measurements enables assessment of pore-throat-size distribution as well as permeability and capillary pressure. However, the reliability of these methods is questionable in rocks with complex/multi-modal pore geometry. The objectives of this paper include (a) reliably estimating a variable constriction factor (a geometric parameter which relates the pore- and throat-size) in rocks with complex pore geometry to accurately quantify pore geometry, which is the main contribution of this work, (b) developing a new rock physics workflow for integrating NMR and electrical conductivity for assessment of permeability and capillary pressure that takes into account a variable constriction factor, and (c) verifying the reliability of the introduced workflow using core scale measurements. The proposed workflow starts with calculating pore-body-size distribution from NMR T2 distribution. Then, we combine electrical resistivity and pore-size distribution to estimate the distribution of constriction factor in the pore structure. Next, we determine pore- throat-size distribution using the estimated variable constriction factor. We then introduce a new permeability model which takes variable constriction factor into account. The inputs to the permeability model include throat-size distribution, tortuosity, and porosity. Finally, we calculate saturation-dependent capillary pressure using the estimated throat-size distribution. We successfully verified the reliability of the introduced workflow in the core-scale domain in carbonate rock samples with complex pore structure. The permeability estimates obtained by the new workflow yielded less than 7% average relative error when compared against core measurements. We also observed a good agreement between the throat-size distribution and capillary pressure estimated from the new workflow and the ones acquired from MICP (mercury injection capillary pressure) measurements. Results also confirmed that integration of a variable constriction factor improves directional permeability estimates compared to cases where an effective constriction factor was used to quantify pore-throat size distribution in rocks with multi-modal pore-size distribution.

scholarly journals Impact of Polymer Binders on the Structure of Highly Filled Zirconia Feedstocks

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2247
Author(s):  
Claire Delaroa ◽  
René Fulchiron ◽  
Eric Lintingre ◽  
Zoé Buniazet ◽  
Philippe Cassagnau
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
High Density Polyethylene ◽  
Mercury Porosimetry ◽  
High Density ◽  
Organic Binder ◽  
Molten State ◽  
Homogeneous Dispersion ◽  
The Impact

The impact of polypropylene and high-density polyethylene backbone binders on the structure of organic matrix, feedstock, and ceramic parts is investigated in terms of morphology in this paper. The miscibility of wax with polyethylene and polypropylene is investigated in the molten state via a rheological study, revealing wax full miscibility with high-density polyethylene and restricted miscibility with polypropylene. Mercury porosimetry measurements realized after wax extraction allow the characterization of wax dispersion in both neat organic blends and zirconia filled feedstocks. Miscibility differences in the molten state highly impact wax dispersion in backbone polymers after cooling: wax is preferentially located in polyethylene phase, while it is easily segregated from polypropylene phase, leading to the creation of large cracks during solvent debinding. The use of a polyethylene/polypropylene ratio higher than 70/30 hinders wax segregation and favors its homogeneous dispersion in organic binder. As zirconia is added to organic blends containing polyethylene, polypropylene, and wax, the pore size distribution created by wax extraction is shifted towards smaller pores. Above zirconia percolation at 40 vol%, the pore size distribution becomes sharp attesting of wax homogeneous dispersion. As the PP content in the organic binder decreases from 100% to 0%, the pore size distribution is reduced of 30%, leading to higher densification ability. In order to ensure a maximal densification of the final ceramic, polyethylene/polypropylene ratios with a minimum content of 70% of high-density polyethylene should be employed.

scholarly journals Physical parameters of Fluvisols on flooded and non-flooded terraces

2017 ◽  
Vol 31 (1) ◽  
pp. 73-82 ◽  
Author(s):  
Milena Kercheva ◽  
Zofia Sokołowska ◽  
Mieczysław Hajnos ◽  
Kamil Skic ◽  
Toma Shishkov
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Mercury Intrusion Porosimetry ◽  
Water Retention Curve ◽  
Anthropogenic Factors ◽  
Physical Parameters ◽  
Water Desorption ◽  
Mercury Intrusion ◽  
The Impact

Abstract The heterogeneity of soil physical properties of Fluvisols, lack of large pristine areas, and different moisture regimes on non-flooded and flooded terraces impede the possibility to find a soil profile which can serve as a baseline for estimating the impact of natural or anthropogenic factors on soil evolution. The aim of this study is to compare the pore size distribution of pristine Fluvisols on flooded and non-flooded terraces using the method of the soil water retention curve, mercury intrusion porosimetry, nitrogen adsorption isotherms, and water vapour sorption. The pore size distribution of humic horizons of pristine Fluvisols on the non-flooded terrace differs from pore size distribution of Fluvisols on the flooded terrace. The peaks of textural and structural pores are higher in the humic horizons under more humid conditions. The structural characteristics of subsoil horizons depend on soil texture and evolution stage. The peaks of textural pores at about 1 mm diminish with lowering of the soil organic content. Structureless horizons are characterized by uni-modal pore size distribution. Although the content of structural pores of the subsoil horizons of Fluvisols on the non-flooded terrace is low, these pores are represented by biopores, as the coefficient of filtration is moderately high. The difference between non-flooded and flooded profiles is well expressed by the available water storage, volume and mean radius of pores, obtained by mercury intrusion porosimetry and water desorption, which are higher in the surface horizons of frequently flooded Fluvisols.

Development of porous SiLK™ Semiconductor Dielectric Resin for the 65 nm and 45 nm Nodes

2003 ◽  
Vol 766 ◽  
Author(s):  
R. J. Strittmatter ◽  
J. L. Hahnfeld ◽  
H. C. Silvis ◽  
T. M. Stokich ◽  
J. D. Perry ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Scale Up ◽  
Process Window ◽  
Pore Morphology ◽  
Monitoring And Control ◽  
Interlayer Dielectric ◽  
The Impact

AbstractPorous SiLK resin is an ultra-low-k interlayer dielectric (ILD) material designed to meet the needs of the 65 nm technology node and beyond. In early 2002, the porous SiLK resin formulation was defined and scaled up, facilitating the tight monitoring and control of key properties, including pore size distribution, over several lots of material. The film processing kinetics are now well understood and a wide process window exists which ensures optimum pore morphology and pore size distribution. Thermal cycling of films demonstrates no effect on pore morphology or dielectric constant. The material has been designed to minimize the impact of CTE mismatch at high temperature, which challenged the integration of some previous generations of SiLK and porous SiLK dielectric resins. The discrete, closed-cell pore geometry is well characterized and enables the extendibility of process module development from SiLK resin technology to porous SiLK resin. Concurrent with the scale up efforts, advancements in minimizing both cure time and temperature simultaneously, as well as significant improvements in pore size and pore size distribution, have been achieved. The cure and porogen burn out time has been reduced by 50% or greater, and the temperature has been reduced to 370°C. The pore size has been reduced by ∼35%, and the pore size distribution has been narrowed by ∼40%. These advancements have resulted in the introduction of porous SiLK T resin, with a dielectric constant of k = 2.4 and a recommended cure temperature of 370°C, and the introduction of porous SiLK U resin, with a mean pore diameter of ∼5 nm and a dielectric constant of k = 2.2.

scholarly journals Combining SEM and Mercury Intrusion Capillary Pressure in the characterization of pore-throat distribution in tight sandstone and its modification by diagenesis: A case study in the Yanchang Formation, Ordos Basin, China

2020 ◽  
Vol 24 (1) ◽  
pp. 19-28
Author(s):  
Wei Wang ◽  
Caili Yu ◽  
Le Zhao ◽  
Shuang Xu ◽  
Lei Gao
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Pore Space ◽  
Ordos Basin ◽  
Pore Throat ◽  
Tight Sandstone ◽  
Nano Scale ◽  
Carbonate Cementation ◽  
Pressure Controlled

Determining the characteristics of pore-throat structures, including the space types present and the pore size distribution, is essential for the evaluation of reservoir quality in tight sandstones. In this study, the results of various testing methods, including scanning electron microscopy (SEM), pressure-controlled porosimetry (PCP) and rate-controlled porosimetry (RCP), were compared and integrated to characterize the pore size distribution and the effects of diagenesis upon it in tight sandstones from the Ordos Basin, China. The results showed that reservoir spaces in tight sandstones can be classified into those with three types of origins (compaction, dissolution, and clay-related) and that the sizes and shapes of pore space differ depending on origin. Considering the data obtained by mercury injection porosimetry and the overestimation of pore radii by pressure-controlled porosimetry, the full-range pore size distribution of tight sandstones can be determined by combining data from PCP with corrected RCP data. The pore-throat radii in tight sandstone vary from 36 nm to 200 μm, and the distribution curve is characterized by three peaks. The right peak remains similar across the sample set and corresponds to residual intergranular pores and dissolution pores. The middle and left peaks show variation between samples due to the heterogeneity and complexity of nano-scale throat bodies. The average micro-scale pore content is 33.49%, and nano-scale throats make up 66.54%. The nano-scale throat spaces thus dominate the reservoir space of the tight sandstones. Compaction, dissolution, carbonate cementation, and clay cementation have various effects on pore-throats. Compaction and carbonate cementation decrease pore body content. Pore-bridging clay cementation decreases throat space content. As pore-lining clay cementation preserves pore space.

scholarly journals Steady-State Water Drainage by Oxygen in Anodic Porous Transport Layer of Electrolyzers: A 2D Pore Network Study

Processes ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 362 ◽  
Author(s):  
Haashir Altaf ◽  
Nicole Vorhauer ◽  
Evangelos Tsotsas ◽  
Tanja Vidaković-Koch
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Network Model ◽  
Phase Interface ◽  
Pore Network ◽  
Transport Layer ◽  
Pore Network Model ◽  
Network Simulations ◽  
The Impact

Recently, pore network modelling has been attracting attention in the investigation of electrolysis. This study focuses on a 2D pore network model with the purpose to study the drainage of water by oxygen in anodic porous transport layers (PTL). The oxygen gas produced at the anode catalyst layer by the oxidation of water flows counter currently to the educt through the PTL. When it invades the water-filled pores of the PTL, the liquid is drained from the porous medium. For the pore network model presented here, we assume that this process occurs in distinct steps and applies classical rules of invasion percolation with quasi-static drainage. As the invasion occurs in the capillary-dominated regime, it is dictated by the pore structure and the pore size distribution. Viscous and liquid film flows are neglected and gravity forces are disregarded. The curvature of the two-phase interface within the pores, which essentially dictates the invasion process, is computed from the Young Laplace equation. We show and discuss results from Monte Carlo pore network simulations and compare them qualitatively to microfluidic experiments from literature. The invasion patterns of different types of PTLs, i.e., felt, foam, sintered, are compared with pore network simulations. In addition to this, we study the impact of pore size distribution on the phase patterns of oxygen and water inside the pore network. Based on these results, it can be recommended that pore network modeling is a valuable tool to study the correlation between kinetic losses of water electrolysis processes and current density.

scholarly journals Describing the Full Pore Size Distribution of Tight Sandstone and Analyzing the Impact of Clay Type on Pore Size Distribution

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-20 ◽  
Author(s):  
Qiang Lei ◽  
Liehui Zhang ◽  
Hongming Tang ◽  
Yulong Zhao ◽  
Man Chen ◽  
...  
Keyword(s):  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Clay Minerals ◽  
Pore Volume ◽  
Tight Sandstone ◽  
Volume Versus ◽  
Intercrystalline Pores ◽  
The Impact ◽  
Pore Volume Versus

Understanding the pore size distribution (PSD) of tight sandstone and the effect of clay minerals on the PSD is important for reservoir evaluation. Due to the complex shape of clay minerals, the multiscale pore size of tight sandstone, and the limitation of different experimental methods, it is hard to characterize the full PSD of tight sandstone, especially the point of connection (POC) of different derived PSD curves. In this paper, a more comprehensive technique integrated different precision methods of N2/CO2 low-pressure adsorption isotherms (N2/CO2-LPAI), mercury injection capillary pressure (MICP), nuclear magnetic resonance (NMR), and synchrotron X-ray computed tomography (XCT) to investigate the full PSD for three typical tight sandstones in China. Two different forms of PSD data presentations, differential pore volume versus diameter (dV/dR) and the log differential pore volume versus diameter (dV/dlogR), were firstly used to determine the POC. The full integrated PSD curves and scanning electron microscopy (SEM) images were carried out on the different clay-rich tight sandstones. The results show that the pores are classified into three types: intercrystalline pores (less than 0.01 μm), clay-related pores and residual intergranular pores (0.01 μm to 10 μm), and microfractures and dissolution pores (greater than 10 μm). The percentage of intercrystalline pores has a small relation on the porosity and connectivity, while there is a strong correlation among microfractures, dissolution pores, porosity, and especially connectivity. The microfractures and dissolution pores are the main connection channels, so a little change of the main connection channels will have a great effect on the permeability of the tight sandstones.

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