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RICHEFEU Vincent
Domaines de Recherche:  Sciences du Vivant/Ingénierie des aliments
 Sciences de l'ingénieur/Génie des procédés
 Informatique/Modélisation et simulation
 Sciences de l'ingénieur/Mécanique
 Sciences de l'ingénieur/Mécanique/Mécanique des matériaux
 Sciences de l'ingénieur/Mécanique/Mécanique des fluides
 Sciences du Vivant
 Physique/Mécanique/Mécanique des matériaux
 Sciences de l'ingénieur/Mécanique/Matériaux et structures en mécanique
 Physique/Mécanique/Matériaux et structures en mécanique
 Sciences de l'ingénieur/Mécanique/Mécanique des solides
 Physique/Mécanique/Mécanique des solides
 Physique/Matière Condensée/Science des matériaux

Dernieres productions scientifiques :


Modélisation discrète de la déconstruction d’aliments  projet AIC MiDiDAM
Auteur(s): Frank Xavier, Delenne J.Y., Lampoh K., Nezamabadi S., Radjai F., Guessasma Sofiane, Della Valle Guy, Kristiawan Magdalena, Reguerre AnneLaure, Jebalia Imen, Richefeu V.
Conference: Métaséminaire CEPIA 2018 (Paris, FR, 20180327)
Actes de conférence: , vol. p. (2018)



Lattice Boltzmann modelling of liquid distribution in unsaturated granular media
Auteur(s): Richefeu V., Radjai F., Delenne J.Y.
(Article) Publié:
Computers And Geotechnics, vol. 80 p.353359 (2016)
Ref HAL: hal01837433_v1
DOI: 10.1016/j.compgeo.2016.02.017
Exporter : BibTex  endNote
6 citations
Résumé: We use capillary condensation simulated by a multiphase Lattice Boltzmann model as a means to generate homogeneous distributions of liquid clusters in 2D granular media. Liquid droplets condense from the vapour phase between and on the grains, and they transform into capillary bonds and liquid clusters as thermodynamic equilibrium is approached. As the amount of condensed liquid is increased, liquid clusters of increasing connectivity are formed and the distribution of liquid undergoes topological transitions until the whole pore space is filled by the liquid. We investigate the cluster statistics and local grain environments. From extensive simulations, we also obtain the mean Laplace pressure as a function of the amount of liquid, which is found to be quite similar to the wellknown experimental retention curve in soil mechanics. The tensile stress carried by the grains increases as a function of the amount of condensed liquid up to a peak in the funicular state beyond which the stress falls off as a result of pressure drop inside the merging clusters.



Lattice Boltzmann modeling of liquid clusters in granular media
Auteur(s): Delenne J.Y., Richefeu V., Radjai F.
(Affiches/Poster)
3. International Symposium on Geomechanics from Micro to Macro (Cambridge, GB), 2015
Ref HAL: hal01837458_v1
Exporter : BibTex  endNote
Résumé: We use capillary condensation simulated by a multiphase Lattice Boltzmann model as a means to generate homogeneous distributions of liquid clusters in 2D granular media. Liquid droplets condense from the vapor phase between and on the grains, and they transform into capillary bonds and liquid clusters as thermodynamic equilibrium is approached. As the amount of condensed liquid is increased, liquid clusters of increasing connectivity are formed and the distribution of liquid undergoes topological transitions until the whole pore space is filled by the liquid. We investigate the cluster statistics and local grain environments. From extensive simulations, we also obtain the mean Laplace pressure as a function of the amount of liquid, which is found to be quite similar to the wellknown experimental retention curve in soil mechanics.



Flowbox
Auteur(s): Delenne J.Y., Richefeu V., Frank Xavier, Radjai F.
(Autres publications)
, 2015
Ref HAL: hal01603489_v1
Exporter : BibTex  endNote
Résumé: The code FLOWbox is dedicated to the computation of flow through porous and granular materials.FLOWbox is based on an optimized 3D Lattice Boltzmann algorithm for the computation of liquid or gas flows directly at the scale of heterogeneities. FLOWbox intends to be a powerful and versatile software able to operate on highly detailed microstructures in a systematic fashion. These microstructures can be generated either from numerical simulation or from tomography.



Distribution of liquid clusters inside a granular packing by LBM
Auteur(s): Richefeu V., Radjai F., Delenne J.Y.
(Affiches/Poster)
Conference on ParticleBased Methods (PARTICLES 2015) (Barcelone, ES), 2015
Ref HAL: hal01568144_v1
Exporter : BibTex  endNote
Résumé: Partially wetted granular materials have remained largely unexplored because of the intricate texturing of water in the pore space [1] in spite of its essential role in many natural and industrial processes. We investigate the distribution of liquid in a granular material and its relationship with capillary stresses as the liquid fills gradually and homogeneously the pore space of a 2D granular packing. The distribution of liquid is computed using a singlecomponent multiphase Lattice Boltzmann Method (LBM) [2]. The thermodynamics of phase change is based on Carnahan Starling's equation of state from which the interactions between liquid, gas and solid are derived using nonlocal potentials. These potentials are calculated between the fluid particles and neighbouring lattice nodes that control the surface tension and contact angle between fluid and solid. A homogeneous grainliquid mixture is obtained allowing for detailed investigation of the statistics of liquid distribution inside the packing at increasing degree of saturation. A percolation algorithm is employed to identify the liquid clusters and to determine their volume and connectivity with the surrounding grains. The internal pressure of the clusters is analysed as a function of liquid content [3]. We are thus able to obtain the global liquidretention curve as well as the forces acting on the grains. The tensile stress carried by the grains as a function of the amount of condensed liquid reveals four distinct states with a peak stress occurring at transition from a primary coalescence process, where the cohesive strength is carried mostly by the grains, to a secondary process governed by the increase of the liquid cluster volumes. Finally, we show that the evolution of capillary states is correctly captured by a simple model accounting for the competing effects of the Laplace pressure and grainliquid interface.


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