Computation of Saturation Dependence of Effective Diffusion Coefficient in Unsaturated Argillite Micro-fracture by Lattice Boltzmann Method
| Autor: | Alain Genty, Soukaina Gueddani, Magdalena Dymitrowska |
|---|---|
| Přispěvatelé: | CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'étude et de recherche sur les transferts et les interactions dans les sous-sols (IRSN/PSE-ENV/SEDRE/LETIS), Service des déchets radioactifs et des transferts dans la géosphère (IRSN/PSE-ENV/SEDRE), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), financial support of the NEEDS-MIPOR program within 'Mission for Interdisciplinarity' of the French National Centre for Scientific Research, PSE-ENV/SEDRE/LETIS, Institut de Radioprotection et de Sûreté Nucléaire (IRSN) |
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
010504 meteorology & atmospheric sciences
[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th] General Chemical Engineering 0208 environmental biotechnology Lattice Boltzmann method Borehole Lattice Boltzmann methods Mineralogy 02 engineering and technology 01 natural sciences Catalysis Physics::Geophysics Effective diffusion TRACER Effective diffusion coefficient Diffusion (business) 0105 earth and related environmental sciences Unsaturated Hydrogeology Mechanics 020801 environmental engineering Fracture Clay Tomography Saturation (chemistry) Geology |
| Zdroj: | Transport in Porous Media Transport in Porous Media, 2017, 117, pp.149-168. ⟨10.1007/s11242-017-0826-z⟩ Transport in Porous Media, Springer Verlag, 2017, 117, pp.149-168. ⟨10.1007/s11242-017-0826-z⟩ |
| ISSN: | 0169-3913 1573-1634 |
| DOI: | 10.1007/s11242-017-0826-z⟩ |
| Popis: | Getting access to the effective diffusion coefficient is a key point to provide realistic predictions of migration of radionuclides from radioactive waste repository in deep argillaceous geological formations. In the present work, the effective diffusion coefficient was computed inside an argillite micro-fracture as a function of its saturation level. The micrometric fracture geometry was extracted from the X-ray $$\mu $$ -tomography image ( $$0.7\,\upmu \mathrm{m}$$ voxel resolution) of an Opalinus clay sample. It was collected in the host rock excavated damaged zone surrounding a borehole in the Mont Terri laboratory. The computations were performed using two two-relaxation-time lattice Boltzmann models. The first one, a phase separation model, was used to extract the connected liquid phase inside the fracture for given saturations. The second, a diffusion model, was used to compute non-reactive tracer diffusion in the connected liquid phase of the fracture and to calculate the effective diffusion coefficient for the associated saturations. The dependence of the effective diffusion coefficient on saturation was found to be quasi-linear and to qualitatively match the Maxwell expression for saturations lower than 0.8. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink