The field of fluid mechanics is rapidly advancing, driven by unprecedented volumes data from experiments, measurements, and large-scale simulations at multiple spatiotemporal scales. Machine learning (ML) offers a wealth techniques to extract ...Read More

A general method for computing the hydrodynamic interactions among N suspended particles, under condition of vanishingly small particle Reynolds number, is presented. The accounts both near-field lubrication effects and dominant many-body interactions. reproduce screening characteristic porous media 'effective viscosity' free suspensions. accurate computationally efficient, permitting dynamic simulation arbitrarily configured many-particle systems. calculated are shown to agree well with...

The newly developed simulation method known as Stokesian dynamics is used to investigate the rheological behaviour of concentrated suspensions. Both detailed microstructure (e.g. pair-distribution function) and macroscopic properties are determined for a suspension identical rigid spherical particles in simple shear flow. suspended interact through both hydrodynamic non-hydrodynamic forces. For suspensions with purely forces, increase viscosity volume fraction ϕ shown be caused by particle...

The viscosity of a suspension spherical Brownian particles is determined by Stokesian dynamics as function the Péclet number. Several new aspects concerning theoretical derivation direct contribution motion to bulk stress are given, along with results obtained from simulation monolayer. simulations reproduce experimental behavior generally observed in dense suspensions, and an explanation this given observing evolution different contributions shear rate. thinning at low numbers due...

A general method is presented for simulating the dynamical behavior of a suspension particles which interact through both hydrodynamic and nonhydrodynamic forces. In molecular-dynamics-like simulation there are two different procedures computing interactions among particles: pairwise additivity forces velocities. The preferred as it preserves lubrication prevent from overlapping. methods compared in monolayer identical rigid non-Brownian spherical simple shear flow. Periodic boundary...

The non-equilibrium behaviour of concentrated colloidal dispersions is studied by Stokesian Dynamics, a general molecular-dynamics-like technique for simulating particles suspended in viscous fluid. simulations are suspension monodisperse Brownian hard spheres simple shear flow as function the Péclet number, Pe , which measures relative importance and forces. Three clearly defined regions revealed. There first Brownian-motion-dominated regime ( ≤ 1) where departures from equilibrium...

A magnetoactive elastomer made of micronic carbonyl iron particles, structured in elongated clusters and embedded a silicon matrix is studied under traction both static dynamic modes. The application magnetic field 120 kA/m induces change elastic moduli about 0.6 MPa at strains 4 to 5%. Still higher changes (4 MPa) are observed storage modulus low (10 -4 10 -3 ). shape the stress-strain curves explained by taking into account existence fiber like structure.

A general method for computing the hydrodynamic interactions among an infinite suspension of particles, under condition vanishingly small particle Reynolds number, is presented. The follows procedure developed by O'Brien (1979) constructing absolutely convergent expressions interactions. For use in dynamic simulation, convergence these accelerated application Ewald summation technique. resulting mobility and/or resistance matrices correctly include all far-field non-convergent Near-field...

The hydrodynamic transport properties of hard-sphere dispersions are calculated for volume fractions (φ) spanning the dilute limit up to fluid–solid transition at φ=0.49. Particle distributions generated by a Monte Carlo technique and interactions Stokesian dynamics simulation. effects changing number particles in simulation cell investigated, scaling laws finite-size derived. using various levels approximation computing both far- near-field also examined. associated with freely mobile...

The self-diffusivity of Brownian hard spheres in a simple shear flow is studied by numerical simulation. Particle trajectories are calculated Stokesian dynamics, with an accurate representation the suspension hydrodynamics that includes both many-body interactions and lubrication. simulations monolayer identical as function Péclet number: Pe =γ̇a2/D0, which measures relative importance forces. Here γ̇ rate, particle radius, D0 diffusion coefficient single sphere at infinite dilution. In...

We present a general method based on multipole-expansion theory that allows us to calculate efficiently and accurately the electrostatic forces dielectric constant of an assembly spheres. This is applied study two aspects which play important role in behavior electrorheological (ER) fluids. The first one concerns calculation principal values ${\mathrm{\ensuremath{\epsilon}}}_{\mathrm{\ensuremath{\parallel}}}$ ${\mathrm{\ensuremath{\epsilon}}}_{\mathrm{\ensuremath{\perp}}}$ tensor...

The yield stress of a magnetorheological suspension is calculated from two different approaches. first one based on mesoscopic description the structure taking only into account shape anisotropy strained aggregates. second microscopic approach where interparticle forces, due to application field, are numerically by magnetostatics between particles inside We show that macroscopic well applies suspensions nonmagnetic in ferrofluid and layered structure, consisting parallel slabs magnetizable...

In this work, the magnetorheological properties of suspensions micron-sized iron particles dispersed in magnetite ferrofluids were studied. With aim, flow steady-state regime investigated using a commercial magnetorheometer with parallel-plate measuring cell. The effect both and concentration on magnitude yield stress was studied for broad range magnetic fields. addition, experimental values compared predictions from chain model. purpose obtained by means finite element calculations....

This work reports a detailed study on the shear magnetorheology of suspensions magnetic microfibers. The steady-state regime was investigated using controlled-stress rheometer for different concentrations particles and under presence broad range applied fields (up to 512kAm−1). results were compared with those obtained conventional magnetorheological fluids (suspensions microspheres). It found that fibers show an enhanced effect. We proposed existence field-dependent solid friction between...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation E. Lemaire, A. Meunier, G. Bossis, J. Liu, D. Felt, P. Bashtovoi, N. Matoussevitch; Influence of the particle size on rheology magnetorheological fluids. Rheol. 1 September 1995; 39 (5): 1011–1020. https://doi.org/10.1122/1.550614 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation O. Volkova, G. Bossis, M. Guyot, V. Bashtovoi, A. Reks; Magnetorheology of magnetic holes compared to particles. J. Rheol. 1 January 2000; 44 (1): 91–104. https://doi.org/10.1122/1.551075 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation G. Bossis, E. Lemaire; Yield stresses in magnetic suspensions. J. Rheol. 1 October 1991; 35 (7): 1345–1354. https://doi.org/10.1122/1.550234 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Dropdown Menu input auto suggest filter your...

This paper reports the first predictions of yield stress suspensions non-Brownian magnetic fibers in presence uniform fields. The quasistatic regime shear deformation (before flow onset) suspension is studied. Four different structures fiber are considered—column, zigzag, three-dimensional stochastic and near-planar structures—and attributed to failure given structure at a critical strain. main contributions found come from restoring torque acting on each solid friction between fibers....

Magnetorheological elastomers (MREs) are smart materials made by aligning magnetic microparticles inside a liquid polymer. Once the polymer is cured, this anisotropic structure kept, giving to composite new properties such as large change in electrical resistivity with applied pressure. In order understand conduction mechanism composites, influence of pressure on metal powders without was first investigated. It found that initial powder at zero about 108 Ω cm for pure nickel and 106 silver...