We report a new kind of field-responsive fluid consisting of suspensions of diamagnetic (DM) and ferromagnetic (FM) microparticles in ferrofluids. We designate them as inverse magnetorheological (IMR) fluids for analogy with inverse ferrofluids (IFFs). Observations on the particle self-assembly in IMR fluids upon magnetic field application showed that DM and FM microparticles were assembled int...

Abstract Microswimmer suspensions in Newtonian fluids exhibit unusual macroscale properties, such as a superfluidic behavior, which can be harnessed to perform work at microscopic scales. Since most biological are non-Newtonian, here we study the rheology of microswimmer suspension weakly viscoelastic shear flow. At individual level, find that stresses generated by activity substantially modify...

The applicability of some constitutive equations for the solid stress tensor used in mixture model to describe shear-induced migration neutrally buoyant particles Newtonian fluids is investigated. It shown that moderately dense suspensions, where direct particle contacts and interparticle forces are negligible, must be due lubrication between particles. Results highlight accounting these part f...

Under an applied traction, highly concentrated suspensions of solid particles in fluids can turn from a state which they flow to counteract the traction as elastic solid: shear-jammed state. Remarkably, suspension back flowing simply by inverting traction. A tensorial model is presented and tested paradigmatic cases. We show that, reproduce phenomenology shear jamming generic geometries, it nec...

SYNOPSIS 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 obtained for conventional magnetorheolog...

This paper is concerned with difficulties encountered by engineers when they attempt to predict the orientation of fibers in creation injection molded plastic parts. It known that Jeffery’s equation, which was designed model a single fiber an infinite fluid, breaks down very badly applied, no modifications, this situation. In previous paper, author described how interactions between and viscosi...

Asphaltene precipitation occurs in petroleum fluids under certain unfavorable conditions, but can be controlled by tuning composition. Aromatic solvents in large quantities can prevent precipitation entirely and can dissolve already precipitated asphaltenes. Some polymeric surfactants can dissolve asphaltenes when added at much lower concentrations than required by aromatic solvents. Other disp...

Submitted for the MAR05 Meeting of The American Physical Society A Coarse-Grained Simulation of Rheology of Colloidal Suspensions and Polymer Nano-Composites VICTOR PRYAMITSYN, University of Texas@Austin, VENKAT GANESAN — We extend DPD model to address dynamical properties of suspensions of solid particles in complex fluids. In this approach, the solvent particles (polymer segments) are represe...

Raiskinmäki, Pasi Dynamics of multiphase flows: liquid-particle suspensions and droplet spreading Jyväskylä: University of Jyväskylä, 2004, 152 p. (Research report/Department of Physics, University of Jyväskylä, ISSN 0075-465X; 7/2004) ISBN 951-39-1967-6 diss. Most fluids that appear in nature as well in numerous applications in industry are multiphase fluids such as liquid-particle suspensions...

The aim of this work is the investigation of the magnetorheological behavior, under both simple steadyand oscillatory-shear flow regimes, of fluids composed by micron-sized iron particles (average diameter 930 ± 330 nm) dispersed in silicone oil. Magnetic fields ranging from 279 A/m (0.35 mT) to 1727 A/m (2.17 mT) were applied to the suspensions. The effect of silica nanoparticles as stabilizer...