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Marzin Tom Desvages Brice Creppy Adama Lépine Louis Esnault-Filet Annette Auradou Harold 《Transport in Porous Media》2020,132(2):283-297
Transport in Porous Media - Microbial-induced carbonate precipitation (MICP) in porous media is a two-step procedure: First, the suspension of bacteria is injected and some of the bacteria get... 相似文献
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The evolution and spatial structure of displacement fronts in fractures with self-affine rough walls are studied by numerical simulations. The fractures are open and the two faces are identical but shifted along their mean plane, either parallel or perpendicular to the flow. An initially flat front advected by the flow is progressively distorted into a self-affine front with a Hurst exponent equal to that of the fracture walls. The lower cutoff of the self-affine regime depends only on the aperture, while the upper cutoff grows with the lateral shift and linearly with the width of the front. 相似文献
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Auradou H. Zei M. Bouchaud E. 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,44(3):365-372
This article reports results concerning the
fracture of a 2d triangular lattice of atoms linked by springs.
The lattice is submitted to controlled strain tests and the influence of both porosity and temperature on failure is investigated.
The porosity is found on one hand to decrease the stiffness of the specimen but on the other hand it increases the deformation
sustained prior to failure.
Temperature is shown to control the ductility due to the presence of cavities that grow and merge.
The rough surfaces resulting from the propagation of the crack exhibit
self-affine properties with a roughness exponent = 0.59 ±
0.07 over a range of length scales which increases with
temperature. Large cavities also have rough walls which are found
to be fractal with a dimension, D, which evolves with the
distance from the crack tip. For large distances, D is found to be
close to 1.5, and close to 1.0 for cavities just before their
coalescence with the main crack. 相似文献
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Eric Clement Anke Lindner Carine Douarche Harold Auradou 《The European physical journal. Special topics》2016,225(11-12):2389-2406
Fluids laden with motile bacteria enter in the category of active matter, a new field currently developing at the convergence of biology, hydrodynamics and statistical physics. Such suspensions were shown recently to exhibit singular macroscopic transport properties. In this paper we review some recent results, either theoretical or experimental, on the active fluid rheology. We focus principally on bacteria suspensions and the objective is to provide the basis for understanding the emergence of the singular constitutive relations characterizing the macroscopic transport properties of such an active fluid under flow. 相似文献
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The geometry of postmortem rough fracture surfaces of porous glass ceramics made of sintered glass beads is shown experimentally to be self-affine with an exponent zeta=0.40+/-0.04, remarkably lower than the "universal" value zeta=0.8 frequently measured for many materials. This low value of zeta is similar to that found for sandstone samples of similar microstructure and is also practically independent on the porosity phi in the range investigated (3%< or =phi< or =26%) as well as on the bead diameter d and of the crack growth velocity. In contrast, the roughness amplitude normalized by d increases linearly with phi while it is still independent, within experimental error, of d and of the crack propagation velocity. An interpretation of this variation is suggested in terms of a transition from transgranular to intergranular fracture propagation with no influence, however, on the exponent zeta. 相似文献
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M. V. D’Angelo B. Semin G. Picard M. E. Poitzsch J. P. Hulin H. Auradou 《Transport in Porous Media》2010,84(2):389-408
The transport of fibers by a fluid flow is investigated in transparent channels modeling rock fractures: the experiments use
flexible polyester thread (mean diameter 280 μm) and water or a water–polymer solution. For a channel with smooth parallel walls and a mean aperture ā = 0.65 mm, both fiber segments of length ℓ = 20–150 mm and “continuous” fibers longer than the channel length have been used: in both the cases, the velocity of the
fibers and its variation with distance could be accounted for while neglecting friction with the walls. For rough self-affine
walls and a continuous gradient of the local mean aperture transverse to the flow, transport of the fibers by a water flow
is only possible in the region of larger aperture (ā ≲ 1.1 mm) and is of “stop and go” type at low velocities. With the polymer solution, the fibers move faster and more continuously
in high aperture regions and their interaction with the walls is reduced; fiber transport becomes also possible in narrower
regions where irreversible pinning occurred for water. In a third rough model with parallel walls and a low mean aperture
ā = 0.65 mm, fiber transport is only possible with the water–polymer solution. The dynamics of fiber deformations and entanglement
during pinning–depinning events and permanent pinning is analyzed. 相似文献
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Yanina Lucrecia Roht Ricardo Chertcoff Jean-Pierre Hulin Harold Auradou Irene Ippolito 《Transport in Porous Media》2018,122(2):421-436
We study the mixing dynamics of a dyed and a clear miscible fluid by an oscillating flow inside an Hele-Shaw cell with randomly distributed circular obstacles. A transparent setup allows us to analyze the distribution of the two fluids and the reversible and irreversible mixing components. At the lower Péclet numbers Pe (based on the averaged absolute fluid velocity), geometrical dispersion due to the disordered flow field between the obstacles is dominant: the corresponding dispersivity is constant with Pe and, at constant Pe, increases with the amplitude of the oscillations and is negligible at small ones. Compared to echo dispersion with only one injection–suction cycle, oscillating flows are shown to provide additional information when the number of oscillations and, as a result, the distance of transverse mixing are varied. Geometrical dispersion is dominant up to a limiting Pe increasing with the amplitude. At higher \({\textit{Pe}}'{\textit{s}}\), the results are similar to those of Taylor dispersion in cells with smooth walls. 相似文献
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