Lift forces on a cylindrical particle in plane Poiseuille flow of shear thinning fluids are investigated by direct numerical simulation. Previous works on this topic for Newtonian fluids show that the two-dimensional channel can be divided into alternating regions defined by the stability of the particle’s equilibrium. We observe stability regions with the same pattern in flows of shear thinnin...

The formation of a thin film by (i) the slow penetration of a gas bubble into a liquid filled tube, (ii) the withdrawal of a planar substrate from a liquid filled gap, is investigated theoretically for the cases of both Newtonian and shear thinning liquids; the latter conforming to either a power law or Ellis model. Formulated as a boundary value problem underpinned by lubrication theory, the a...

We use a lattice-Boltzmann (LB) kinetic scheme for modelling amphiphilic mixtures to impose Couette flow on self-assembled gyroid mesophase. We report evidence of non-Newtonian behaviour (“shear thinning”) and we show that the particular lack of inversion symmetry which characterizes the gyroid unit cell does not quantitatively affect the flow dynamics beyond a certain predictable shear velocit...

A microcantilever based method for fluid viscosity and mass density measurements with high temporal resolution and microliter sample consumption is presented. Nanomechanical cantilever vibration is driven by photothermal excitation and detected by an optical beam deflection system using two laser beams of different wavelengths. The theoretical framework relating cantilever response to the visco...

The rheological behaviour of ethylene glycol-based nanofluids containing hexagonal scalenohedral-shaped α-Fe2O3 (hematite) nanoparticles at 303.15 K and particle weight concentrations up to 25% has been carried out using a cone-plate Physica MCR rheometer. The tests performed show that the studied nanofluids present non-Newtonian shear-thinning behaviour. In addition, the viscosity at a given s...

We use molecular dynamics simulations to study the behavior of a compressible Lennard-Jones fluid in simple shear flow in a two-dimensional nanochannel. The system is equilibrated in the fluid phase close to the triple point at which gas, liquid and solid phases coexist and is subjected to steady shear in Couette geometry. It is observed that at higher shear rates, the system develops a density...

Rod-like fillers in a flow field of viscous fluid may form complex structures after passing sudden contraction. The rods start with dilute distribution random positions and orientations. Behind the contraction, large amount tumble spatially correlated way, such that orientations perpendicular to occur at regular distances along channel. tumbling results from an interplay several effects, inferr...

A recently developed first-principles approach to the non-linear rheology of dense colloidal suspensions is evaluated and its results compared to those from simulations of sheared systems close to their glass transitions. The predicted scenario of a universal transition of the structural dynamics between yielding of glasses and non-Newtonian (shear-thinning) fluid flow appears well obeyed, and ...

We study the dynamics of shear-band formation and evolution using a simple rheological model. The description couples the local structure and viscosity to the applied shear stress. We consider in detail the Couette geometry, where the model is solved iteratively with the Navier-Stokes equation to obtain the time evolution of the local velocity and viscosity fields. It is found that the underlyi...