M
A
Last name: MEUNIER
First name: Alain
International audience
We have developed a numerical simulation including many body hydrodynamic interactions which allows to reproduce particle's migration in a monodisperse or a bidisperse suspension placed in a two dimensional Couette flow. The concentration profiles obtained by numerical simulation have been compared to the predictions of models based on the...
We have performed numerical simulations of a monolayer of a bidisperse suspension of colloidal particles in a cylindrical Couette flow taking into account hydrodynamic interactions (HI). We compare our simulation results with a simple phenomenological model and obtain good agreement for the monodisperse case. For a bidisperse suspension, we...
Capture of micron-sized magnetic particles on high gradient magnetic separators has been studied for decades in view of broad applications to ore benefication and to magnetic separation of biological cells. Filtration of magnetic nanoparticles, as small as 10-20 nm in diameter, is often considered as practically irrelevant because of the...
Discontinuous shear thickening is a phenomenon observed in concentrated suspensions where, at a given applied stress, the flow becomes suddenly partially blocked and the shear rate begins to decrease and to oscillate when the stress is increased above the critical one. In this work, we show that it is possible to control with a magnetic field...
We present an experimental work performed on a vibrated granular gas enclosed into a 2D-cell. Experimental investigations are performed in microgravity during parabolic flights. High speed video recording and optical tracking allow to obtain the full kinematics of the particles allowing the determination of all inelastic parameters as well as...
The shear-induced microstructure in non-Brownian suspensions is studied. The Pair Distribution Function in the shear plane is experimentally determined for particle volume fractions ranging from 0.05 to 0.56. Transparent suspensions made of PMMA particles (172µm in diameter) dispersed in a fluorescent index matched Newtonian liquid is sheared...
Capture of micron-sized magnetic particles on high gradient magnetic separators has been studied for decades in view of broad applications to ore benefication and to magnetic separation of biological cells. Filtration of magnetic nanoparticles, as small as 10-20 nm in diameter, is often considered as practically irrelevant because of the...
We present experimental results showing an increase of stress of about 150kPa for a weak applied magnetic field (H<10kA/m) in an aqueous suspension of carbony iron particles coated with a superplasticizer molecule used in cement industry. These values, which are several orders of magnitude larger than those classically obtained with...
Different samples of cobalt powder were synthesized. Particle size and shape were characterized by electron microscopy and light scattering. These measures showed that the synthesized powders consisted of monodisperse spheres with average diameters ranging between 63 and 760 nm. These powders were used for the preparation of magnetorheological...
Water pollution is an important problem for the environment. The presence of inorganic and organic pollutants, like metallic cations or polyaromatic hydrocarbons (PAHs), causes environmental damage and provokes different health diseases. Many techniques are currently used to extract these pollutants from water but most of them do not allow...
No description
Water pollution is an important problem for the environment. The presence of inorganic and organic pollutants, like metallic cations or polyaromatic hydrocarbons (PAHs), causes environmental damage and provokes different health diseases. Many techniques are currently used to extract these pollutants from water but most of them do not allow...
No description
This paper is focused on the theoretical modeling of the rheological properties of the magnetic suspensions in shear flows under an external magnetic field aligned with the streamlines. The conventional theory postulates that the field-induced aggregates of magnetic particles are highly anisotropic and aligned with the flow direction....
We present a review of recent experimental and theoretical results on the magnetorheology of fiber suspensions in magnetic fields perpendicular to the shear as well as of suspensions of spherical magnetic particles in longitudinal magnetic fields. Both these problems reveal essentially similar physics. Upon magnetic field application, both...
We present a review of recent experimental and theoretical results on the magnetorheology of fiber suspensions in magnetic fields perpendicular to the shear as well as of suspensions of spherical magnetic particles in longitudinal magnetic fields. Both these problems reveal essentially similar physics. Upon magnetic field application, both...
This work reports a detailed study on the shear magnetorheology of suspensions of magnetic microfibers. The steady-state regime was investigated using a controlled-stress rheometer for different concentrations of particles and under the presence of a broad range of applied magnetic fields up to 512 kA m−1 . The results were compared with those...
This work reports a detailed study on the shear magnetorheology of suspensions of magnetic microfibers. The steady-state regime was investigated using a controlled-stress rheometer for different concentrations of particles and under the presence of a broad range of applied magnetic fields up to 512 kA m−1 . The results were compared with those...
This work is focused on the theoretical modeling of the rheological properties of the magnetic suspensions in shear flows under an external magnetic field aligned with the streamlines. The conventional theory postulates that the field-induced aggregates of magnetic particles are highly anisotropic and aligned with the flow direction. Therefore,...
This work is focused on the theoretical modeling of the rheological properties of the magnetic suspensions in shear flows under an external magnetic field aligned with the streamlines. The conventional theory postulates that the field-induced aggregates of magnetic particles are highly anisotropic and aligned with the flow direction. Therefore,...
If a suspension of magnetic micron-sized and nano-sized particles is subjected to a homogeneous magnetic field, the nanoparticles are attracted to the microparticles and form thick anisotropic halos (clouds) around them. Such clouds can hinder approach of microparticles and result in effective repulsion between them [Lopez-Lopez et al. Soft...
The kinetics of aggregation of non Brownian magnetizable particles in the presence of a magnetic field is studied both theoretically and by means of computer simulations. Theoretical approach is based on a system of Smoluchowski equations for the distribution function of the number of particles in linear chain-like aggregates. Results obtained...
International audience
The kinetics of aggregation of non Brownian magnetizable particles in the presence of a magnetic field is studied both theoretically and by means of computer simulations. Theoretical approach is based on a system of Smoluchowski equations for the distribution function of the number of particles in linear chain-like aggregates. Results obtained...