Pore structure

Micro CT of porous medium: Pores of the porous medium shown as purple color and impermeable porous matrix shown as green-yellow color.

Pore structure is a common term employed to characterize the porosity, pore size, pore size distribution, and pore morphology (such as pore shape, surface roughness, and tortuosity of pore channels) of a porous medium.[1][2] Pores are the openings in the surfaces impermeable porous matrix which gases, liquids, or even foreign microscopic particles can inhabit them.[3] The pore structure and fluid flow in porous media are intimately related.

With micronanoscale pore radii, complex connectivity, and significant heterogeneity,[4] the complexity of the pore structure affects the hydraulic conductivity and retention capacity of these fluids.[5] The intrinsic permeability is the attribute primarily influenced by the pore structure, and the fundamental physical factors governing fluid flow and distribution are the grain surface-to-volume ratio and grain shape.[6]

The idea that the pore space is made up of a network of channels through which fluid can flow is particularly helpful. Pore openings are the comparatively thin sections that divide the relatively large portions known as pore bodies. Other anatomical analogies include "belly" or "waist" for the broad region of a pore and "neck" or "throat" for the constrictive part. Pore bodies are the intergranular gaps with dimensions that are generally significantly smaller than those of the surrounding particles in a medium where textural pore space predominates, such as sand. On the other hand, a wormhole[7] can be regarded as a single pore if its diameter is practically constant over its length.

Such pores can have one of three types of boundaries: (1) constriction, which is a plane across the locally narrowest part of the pore space; (2) interface with another pore (such as a wormhole or crack); or (3) interface with solid.[8]

  1. ^ Tang, H. P.; Wang, J.; Qian, Ma (1 January 2015). "28 - Porous titanium structures and applications". Titanium Powder Metallurgy. Butterworth-Heinemann: 533–554. doi:10.1016/b978-0-12-800054-0.00028-9. ISBN 9780128000540.
  2. ^ Gao, Qian-Feng; Jrad, Mohamad; Hattab, Mahdia; Fleureau, Jean-Marie; Ameur, Lamine Ighil (1 June 2020). "Pore Morphology, Porosity, and Pore Size Distribution in Kaolinitic Remolded Clays under Triaxial Loading". International Journal of Geomechanics. 20 (6): 04020057. doi:10.1061/(asce)gm.1943-5622.0001682. S2CID 216280837.
  3. ^ "Pore size measurement :: Anton Paar Wiki". Anton Paar (in French).
  4. ^ Dai, Quanqi; Wang, Guiwen; Zhao, Xing; Han, Zongyan; Lu, Kai; Lai, Jin; Wang, Song; Li, Dong; Li, Yafeng; Wu, Kunyu (1 August 2021). "Fractal model for permeability estimation in low-permeable porous media with variable pore sizes and unevenly adsorbed water lay". Marine and Petroleum Geology. 130: 105135. Bibcode:2021MarPG.13005135D. doi:10.1016/j.marpetgeo.2021.105135. ISSN 0264-8172. S2CID 236308390.
  5. ^ Scholz, Christian; Wirner, Frank; Klatt, Michael A.; Hirneise, Daniel; Schröder-Turk, Gerd E.; Mecke, Klaus; Bechinger, Clemens (30 October 2015). "Direct relations between morphology and transport in Boolean models". Physical Review E. 92 (4): 043023. Bibcode:2015PhRvE..92d3023S. doi:10.1103/PhysRevE.92.043023. PMID 26565348.
  6. ^ Torskaya, T.; Shabro, V.; Torres-Verdín, C.; Salazar-Tio, R.; Revil, A. (March 2014). "Grain Shape Effects on Permeability, Formation Factor, and Capillary Pressure from Pore-Scale Modeling". Transport in Porous Media. 102 (1): 71–90. Bibcode:2014TPMed.102...71T. doi:10.1007/s11242-013-0262-7. S2CID 53326234.
  7. ^ Tillman, Nola Taylor; published, Ailsa Harvey (13 January 2022). "What is a Wormhole?". Space.com.
  8. ^ Nimmo, J.R. (2013). "Porosity and Pore Size Distribution". Reference Module in Earth Systems and Environmental Sciences: B9780124095489052659. doi:10.1016/B978-0-12-409548-9.05265-9. ISBN 9780124095489.