Procédés et mécanique aux petites échelles PROMETHEE
Deformable micro-objects under hydrodynamic forcing
Microfluidics and Processes
Flow organization at small scales
Membrane separations
suite...
Processes and Small Scales Mechanics Team
Présentation
The PROMETHEE team develops marked competences in the field of continuum mechanics and process engineering, while combining experimental approaches with the development of theories and models. The originality of the studies carried out is declined according to several specificities:
Micro-nano scale of observation and analysis that evacuates the problems related to turbulence (Stokes regime) but requires to consider aspects at the boundaries of the discipline;
Predominant role of interfaces: interactions with solid walls at the nano scale (nano-tubes), fluid-structure interaction with fluid or polymerized membranes at the meso scale;
Connection with complex fluids, soft matter and biological systems.
On the theme of micro- and nano-fluidics, the objects of study, physico-chemical (drops, capsules,...) and biological (vesicles, red blood cells,...), also include the intensified processes of encapsulation and vectorization by microreactor, themes in full expansion. The team is also developing tools for characterizing the organization at small scales such as the development of numerical simulations to account for the segregation obtained within granular media and the development of chemical methods to characterize the effects of micromixing (mixing at the molecular scale). In addition to this, we are involved in the characterization and thermodynamic modeling of complex media.
The numerical tools developed and implemented are varied: boundary integral, finite elements, immersed boundary method, Lattice Boltzman method...
Revaz Chachanidze, Kaili Xie, Jinming Lyu, Marc Jaeger, Marc Leonetti. Breakups of Chitosan microcapsules in extensional flow. Journal of Colloid and Interface Science, 2023, 629, pp.445-454. ⟨10.1016/j.jcis.2022.08.169⟩. ⟨hal-03787637⟩ Plus de détails...
The controlled rupture of a core-shell capsule and the timely release of encapsulated materials are essential steps of the efficient design of such carriers. The mechanical and physico-chemical properties of their shells (or membranes) mainly govern the evolution of such systems under stress and notably the link between the dynamics of rupture and the mechanical properties. This issue is addressed considering weakly cohesive shells made by the interfacial complexation of Chitosan and PFacid in a planar extensional flow. Three regimes are observed, thanks to the two observational planes. Whatever the time of reaction in membrane assembly, there is no rupture in deformation as long as the hydrodynamic stress is below a critical value. At low times of complexation (weak shear elastic modulus), the rupture is reminiscent of the breakup of droplets: a dumbell or a waist. Fluorescent labelling of the membrane shows that this process is governed by continuous thinning of the membrane up to the destabilization. It is likely that the membrane shows a transition from a solid to liquid state. At longer times of complexation, the rupture has a feature of solid-like breakup (breakage) with a discontinuity of the membrane. The maximal internal constraint determined numerically marks the initial location of breakup as shown. The pattern becomes more complex as the elongation rate increases with several points of rupture. A phase diagram in the space parameters of the shear elastic modulus and the hydrodynamic stress is established.
Revaz Chachanidze, Kaili Xie, Jinming Lyu, Marc Jaeger, Marc Leonetti. Breakups of Chitosan microcapsules in extensional flow. Journal of Colloid and Interface Science, 2023, 629, pp.445-454. ⟨10.1016/j.jcis.2022.08.169⟩. ⟨hal-03787637⟩
Antoine Galko, Simon Gsell, Umberto d'Ortona, Laurent Morin, Julien Favier. Pulsated Herschel-Bulkley flows in two-dimensional channels: A model for mucus clearance devices. Physical Review Fluids, 2022, 7 (5), pp.053301. ⟨10.1103/PhysRevFluids.7.053301⟩. ⟨hal-03863329⟩ Plus de détails...
Umberto d'Ortona, Nathalie Thomas, Richard M Lueptow. Mechanisms for recirculation cells in granular flows in rotating cylindrical rough tumblers. Physical Review E, 2022. ⟨hal-03431772v2⟩ Plus de détails...
Friction at the endwalls of partially-filled horizontal rotating tumblers induces curvature and axial drift of particle trajectories in the surface flowing layer. Here we describe the results of a detailed discrete element method study of the dry granular flow of monodisperse particles in threedimensional cylindrical tumblers with endwalls and cylindrical wall that can be either smooth or rough. Endwall roughness induces more curved particle trajectories, while a smooth cylindrical wall enhances drift near the endwall. This drift induces recirculation cells near the endwall. The use of mixed roughness (cylindrical wall and endwalls having different roughness) shows the influence of each wall on the drift and curvature of particle trajectories as well as the modification of the free surface topography. The effects act in opposite directions and have variable magnitude along the length of the tumbler such that their sum determines both direction of net drift and the recirculation cells. Near the endwalls, the dominant effect is always the endwall effect, and the axial drift for surface particles is toward the endwalls. For long enough tumblers, a counter-rotating cell occurs adjacent to each of the endwall cells having a surface drift toward the center because the cylindrical wall effect is dominant there. These cells are not dynamically coupled with the two endwall cells. The competition between the drifts induced by the endwalls and the cylindrical wall determines the width and drift amplitude for both types of cells.
Umberto d'Ortona, Nathalie Thomas, Richard M Lueptow. Mechanisms for recirculation cells in granular flows in rotating cylindrical rough tumblers. Physical Review E, 2022. ⟨hal-03431772v2⟩
Pierrette Guichardon, Carlos Baqueiro, Nelson Ibaseta. Villermaux–Dushman Test of Micromixing Characterization Revisited: Kinetic Effects of Acid Choice and Ionic Strength. Industrial and engineering chemistry research, 2021, 60 (50), pp.18268-18282. ⟨10.1021/acs.iecr.1c03208⟩. ⟨hal-03597451⟩ Plus de détails...
The well-known Villermaux-Dushman system is nowadays widely used for examining the micromixing efficiency either in batch or continuous intensified reactors. However, a bibliographic review shows that kinetic data are too scattered for a reliable determination of the micromixing times. The Dushman reaction kinetics is then reexamined with the use of sulfuric and perchloric acids. The results confirm the fifth-order rate law. More precisely, the I-, H+, and IO3- dependence orders on the rate law are, respectively, 2, 2, and 1, under any condition. To be more consistent with the reactant concentrations used in the Villermaux-Dushman test, we extend their studied range, namely, 1.6 x 10(-3) M <= [I-](0) <= 1.6 x 10(-2) M, 1.2 x 10(-4) M <= [H+](0) <= 1.57 x 10(-2) M, and 4 x 10(-5) M <= [IO3-] <= 2.1 X 10(-4) M. The ionic strength varies up to 2 M. The experimental results show that the rate constant is still ionic-strength-dependent. The results obtained with sulfuric and perchloric acids are found to be consistent and in relatively good agreement at small ionic strengths (mu < 0.1 M) only. At a higher ionic strength, the use of sulfuric acid requires sustained attention to the constant of the second dissociation equilibrium. The nonideal solution behavior raising at a high ionic strength makes its estimation deeply sensitive.
Pierrette Guichardon, Carlos Baqueiro, Nelson Ibaseta. Villermaux–Dushman Test of Micromixing Characterization Revisited: Kinetic Effects of Acid Choice and Ionic Strength. Industrial and engineering chemistry research, 2021, 60 (50), pp.18268-18282. ⟨10.1021/acs.iecr.1c03208⟩. ⟨hal-03597451⟩
Journal: Industrial and engineering chemistry research
Pierrette Guichardon, Carlos Baqueiro, Nelson Ibaseta. Villermaux–Dushman Test of Micromixing Characterization Revisited: Kinetic Effects of Acid Choice and Ionic Strength. Industrial and engineering chemistry research, 2021, 60 (50), pp.18268-18282. ⟨10.1021/acs.iecr.1c03208⟩. ⟨hal-03514628⟩ Plus de détails...
The well-known Villermaux-Dushman system is nowadays widely used for examining the micromixing efficiency either in batch or continuous intensified reactors. However, a bibliographic review shows that kinetic data are too scattered for a reliable determination of the micromixing times. The Dushman reaction kinetics is then reexamined with the use of sulfuric and perchloric acids. The results confirm the fifth-order rate law. More precisely, the I-, H+, and IO3- dependence orders on the rate law are, respectively, 2, 2, and 1, under any condition. To be more consistent with the reactant concentrations used in the Villermaux-Dushman test, we extend their studied range, namely, 1.6 x 10(-3) M <= [I-](0) <= 1.6 x 10(-2) M, 1.2 x 10(-4) M <= [H+](0) <= 1.57 x 10(-2) M, and 4 x 10(-5) M <= [IO3-] <= 2.1 X 10(-4) M. The ionic strength varies up to 2 M. The experimental results show that the rate constant is still ionic-strength-dependent. The results obtained with sulfuric and perchloric acids are found to be consistent and in relatively good agreement at small ionic strengths (mu < 0.1 M) only. At a higher ionic strength, the use of sulfuric acid requires sustained attention to the constant of the second dissociation equilibrium. The nonideal solution behavior raising at a high ionic strength makes its estimation deeply sensitive.
Pierrette Guichardon, Carlos Baqueiro, Nelson Ibaseta. Villermaux–Dushman Test of Micromixing Characterization Revisited: Kinetic Effects of Acid Choice and Ionic Strength. Industrial and engineering chemistry research, 2021, 60 (50), pp.18268-18282. ⟨10.1021/acs.iecr.1c03208⟩. ⟨hal-03514628⟩
Journal: Industrial and engineering chemistry research
Mercredi 16 juin 2021
- De la vague déferlante au globule rouge / Soutenance HDR Paul Gang CHEN
Dr. Paul Gang CHEN
Date de soutenance : le mercredi 16 juin à 15h00 (visio - Zoom)
Résumé : au cours de cette soutenance, je présenterai mes différents travaux sur la modélisation et la simulation numérique d’écoulements interfaciaux : de la vague déferlante au globule rouge.
Jury :
M. Daniel Henry, LMFA, École Centrale de Lyon, Rapporteur
M. Grétar Tryggvason, Johns Hopkins University, Rapporteur
M. Stéphane Zaleski, d’Alembert, Sorbonne Université, Rapporteur
M. Richard Saurel, LMA, Aix-Marseille Université
M. Marc Jaeger, M2P2, École Centrale de Marseille, Tuteur
M. Marc Leonetti, LRP, Grenoble, Invité
Mardi 16 Mars
- Preparation of polyurea microcapsules calibrated in size and shell thickness by a microfluidic process for the absorption of ultraviolet / Soutenance de thèse Jiupeng DU
Doctorant : Jiupeng DU
Date de soutenance : le mardi 16 mars à 14h00 en VISIO
Abstract : This thesis aims to exploit the advantages of microfluidics for the production of polyurea microcapsules. Because of its ability to produce drops with a very narrow size distribution, microfluidic emulsification shows great interest as the first step for rapid interfacial polymerisation. Although the literature on the production of drops in microchannels is abundant, commonly used organic solvents are limited to certain toxic hydrocarbon oils or ketones, as these solvents are very hydrophobic and therefore easy to emulsify in water.
The first part of the work concentrates on the feasibility of emulsifying two less hydrophobic green solvents (dibutyl adipate and n-butyl acetate) in water and study the different flow regimes within a hydrophilic flow-focusing microchannel of glass. The results show that the wetting of the walls by dibutyl adipate can be modified by adding a surfactant (Tween 80). However, the formation of the drops being much faster than the transfer of the surfactant to the interface of the drop being formed, concentrations much higher than the critical micellar concentration are necessary to avoid wetting of the walls by the dispersed phase and thus the appearance of disordered flow regimes. The behavior of the n-butyl acetate/water system is similar, but the comparison of the flow maps for the two systems raises the question of the choice of dimensional numbers for representing the transition between the dripping and jetting regimes.
In the second part, the addition of an interfacial polymerization within the emulsion formed by microfluidics is studied in detail. We aim to fabricate polyurea microcapsules calibrated in size and shell thickness containing octyl salicylate (OS). These microcapsules are used to study, for the first time, the influence of the shell thickness of microcapsules on their absorption efficiency against ultraviolet (UV) light. The results show that an increase of the concentration of isocyanate (HDB-LV or hexamethylene diisocyanate biuret) in the organic phase increases the shell thickness of the microcapsules, their encapsulation efficiency and very moderately their average absorbance. The average absorbance of the microcapsules is inversely proportional to the size of the microcapsules (for the same mass of OS). A theoretical model is proposed to estimate the average absorbance as a function of the mass fraction of HDB-LV in the organic phase and of the size of microcapsules. Finally, the concentration of amine (ethylenediamine) has been optimized to ensure the spherical shape of the microcapsules.
Jury:
Marc LEONETTI (CNRS, LRP), Rapporteur
Nathalie LE SAUZE (Univ Toulouse III), Rapportrice