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Gas permeability evolution of coal samples is investigated with a newly developed three-dimensional fluid-mechanical coupled experimental system. X-ray CT is used to investigate the internal structure of the coal samples and delivers the basis to set-up numerical twins. The work focuses on coal samples with inclusions. A novel coupling procedure between two different tools\u2014discontinuum and continuum codes\u2014is established to simulate the permeability evolution. The permeability is related to the crack pattern in general, and crack width in particular. A prediction of permeability is proposed based on fracture distribution and microcrack behavior. The experimental studies validated the coupling approach. Shear fractures cause substantial permeability enhancement. Piecewise relations between permeability and volumetric strain can be used to fit the whole process, where a nonlinear exponential relation is established after the expansion point. The inclusions as important structural characteristics influence this relation significantly.<\/jats:p>","DOI":"10.3390\/ma15238567","type":"journal-article","created":{"date-parts":[[2022,12,1]],"date-time":"2022-12-01T04:28:57Z","timestamp":1669868937000},"page":"8567","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Gas Permeability Evolution of Coal with Inclusions under Triaxial Compression-Lab Testing and Numerical Simulations"],"prefix":"10.3390","volume":"15","author":[{"given":"Yufeng","family":"Zhao","sequence":"first","affiliation":[{"name":"Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heinz","family":"Konietzky","sequence":"additional","affiliation":[{"name":"Geotechnical Institute, TU Bergakademie Freiberg, 09599 Freiberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Fr\u00fchwirt","sequence":"additional","affiliation":[{"name":"Geotechnical Institute, TU Bergakademie Freiberg, 09599 Freiberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8122-7300","authenticated-orcid":false,"given":"H.W.","family":"Zhou","sequence":"additional","affiliation":[{"name":"School of Energy and Mining Engineering, China University of Mining and Technology, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1016\/S0166-5162(03)00030-2","article-title":"Behavior and Effect of Different Coal Microlithotypes during Gas Transport for Carbon Dioxide Sequestration into Coal Seams","volume":"53","author":"Karacan","year":"2003","journal-title":"Int. J. Coal Geol."},{"key":"ref_2","first-page":"308","article-title":"Adsorption Characteristics of Coal Reservoirs in North China and Its Influencing Factors","volume":"36","author":"Yao","year":"2007","journal-title":"Zhongguo Kuangye Daxue Xuebao\/J. China Univ. Min. Technol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/j.coal.2007.07.003","article-title":"Fractal Characterization of Adsorption-Pores of Coals from North China: An Investigation on CH4adsorption Capacity of Coals","volume":"73","author":"Yao","year":"2008","journal-title":"Int. J. Coal Geol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/S0166-5162(98)00031-7","article-title":"Production Characteristics and Reservoir Analysis of Coalbed Methane Reservoirs","volume":"38","author":"Zuber","year":"1998","journal-title":"Int. J. Coal Geol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1016\/S0098-3004(00)00116-3","article-title":"Acquisition, Optimization and Interpretation of x-Ray Computed Tomographic Imagery: Applications to the Geosciences","volume":"27","author":"Ketcham","year":"2001","journal-title":"Comput. Geosci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.earscirev.2013.04.003","article-title":"High-Resolution X-Ray Computed Tomography in Geosciences: A Review of the Current Technology and Applications","volume":"123","author":"Cnudde","year":"2013","journal-title":"Earth-Sci. Rev."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1016\/j.coal.2007.06.001","article-title":"Determination of the Cleat Angle Distribution of the RECOPOL Coal Seams, Using CT-Scans and Image Analysis on Drilling Cuttings and Coal Blocks","volume":"73","author":"Wolf","year":"2008","journal-title":"Int. J. Coal Geol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"409","DOI":"10.1016\/S1365-1609(02)00065-5","article-title":"Numerical Methods in Rock Mechanics","volume":"39","author":"Jing","year":"2002","journal-title":"Int. J. Rock Mech. Min. Sci."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"6924","DOI":"10.1002\/2014JB011198","article-title":"Failure Mechanisms in Coal: Dependence on Strain Rate and Microstructure","volume":"119","author":"Zhao","year":"2010","journal-title":"J. Geophys. Res. Solid Earth Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1016\/j.tecto.2013.11.014","article-title":"Numerical Study of Variation in Biot\u2019s Coefficient with Respect to Microstructure of Rocks","volume":"610","author":"Tan","year":"2014","journal-title":"Tectonophysics"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1680\/geot.1979.29.1.47","article-title":"A Discrete Numerical Model for Granular Assemblies","volume":"29","author":"Cundall","year":"1979","journal-title":"Geotechnique"},{"key":"ref_12","first-page":"41","article-title":"Stress-Strain, Strength and Failure Behavior of Postaer Sandstone in Tension and Compression Tests\u2013Laboratory Investigations and Numerical Modelling with PFC3D","volume":"Volume 1","author":"Baumgarten","year":"2012","journal-title":"Proceedings of the 41 Geomechanik-Kolloquium"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1329","DOI":"10.1016\/j.ijrmms.2004.09.011","article-title":"A Bonded-Particle Model for Rock","volume":"41","author":"Potyondy","year":"2004","journal-title":"Int. J. Rock Mech. Min. Sci."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"978","DOI":"10.1002\/nag.848","article-title":"Discrete Element Modeling of Direct Shear Tests for a Granular Material","volume":"34","author":"Yan","year":"2010","journal-title":"Int. J. Numer. Anal. Methods Geomech."},{"key":"ref_15","first-page":"381","article-title":"Test Study on Permeability Properties of Coal Specimen in Complete Stress-Strain Process","volume":"28","author":"Yang","year":"2007","journal-title":"Rock Soil Mech."},{"key":"ref_16","unstructured":"Tan, X. (2013). Hydro-Mechanical Coupled Behavior of Brittle Rocks\u2014Laboratory Experiments and Numerical Simulations, Technischen Universit\u00e4t Bergakademie Freiberg."},{"key":"ref_17","first-page":"2482","article-title":"Research on Measuring Method of Permeability by Using Storage-Variable Transient Pulse Method","volume":"27","author":"Li","year":"2008","journal-title":"Chin. J. Rock Mech. Eng."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1016\/0148-9062(75)91244-9","article-title":"Effect of Stress on Permeability of Coal","volume":"12","author":"Somerton","year":"1975","journal-title":"Int. J. Rock Mech. Min. Sci. Geomech."},{"key":"ref_19","first-page":"484","article-title":"Quantification of Fluid Flow: Hydro-Mechanical Behaviour of Different Natural Rough Fractures","volume":"69","author":"Lespinasse","year":"2000","journal-title":"J. Geochem. Explor."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"967","DOI":"10.1016\/S1365-1609(01)00060-0","article-title":"Influence of Asperity Degradation on the Mechanical Behavior of Rough Rock Joints under Cyclic Shear Loading","volume":"38","author":"Lee","year":"2001","journal-title":"Int. J. Rock Mech. Min. Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"5319","DOI":"10.1007\/s00603-021-02436-9","article-title":"Damage Evolution of Coal with Inclusions Under Triaxial Compression","volume":"54","author":"Zhao","year":"2021","journal-title":"Rock Mech. Rock Eng."},{"key":"ref_22","unstructured":"(2008). PFC3D-Particle Flow Code in 3 Dimensions, Itasca Consulting Group Inc.. Verion 3.10-305."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"L22402","DOI":"10.1029\/2008GL035622","article-title":"Multiscale Relationships between Fracture Length, Aperture, Density and Permeability","volume":"35","author":"Neuman","year":"2008","journal-title":"Geophys. Res. Lett."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1029\/1999RG000074","article-title":"Scaling of Fracture Systems in Geological Media","volume":"39","author":"Bonnet","year":"2001","journal-title":"Rev. Geophys."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1016","DOI":"10.1029\/WR016i006p01016","article-title":"Validity of Cubic Law for Fluid Flow in a Deformable Rock Fracture","volume":"16","author":"Witherspoon","year":"1980","journal-title":"Water Resour. Res."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/0148-9062(76)90003-6","article-title":"The Shear Strength of Rock and Rock Joints","volume":"13","author":"Barton","year":"1976","journal-title":"Int. J. Rock Mech. Min. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1191","DOI":"10.1016\/j.ijrmms.2004.05.005","article-title":"Stress-Dependent Permeability of Fractured Rock Masses: A Numerical Study","volume":"41","author":"Rutqvist","year":"2004","journal-title":"Int. J. Rock Mech. Min. 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