Dense suspensions of small strongly interacting particles are complex systems that are rarely understood on the microscopic level. We investigate properties of dense suspensions and sediments of small spherical Al2O3 particles in a shear cell by means of a combined molecular-dynamics and stochastic rotation dynamics simulation. We study structuring effects and the dependence of the suspension's...

Shear-induced particle migration was investigated by using a continuum diffusive -flux model for the creep flow of nickel powder filled polymers, which are viscous with shear-thinning characteristic. The model, together with flow equations, was employed for solving the non-Newtonian flow patterns and non-uniform particle concentration distribution of mono-modal suspensions in a pressure-driven ...

The nonlinear rheological properties of dense suspensions are discussed within simplified models, suggested by a recent first principles approach to the model of Brownian particles in a constant-velocity-gradient solvent flow. Shear thinning of colloidal fluids and dynamical yielding of colloidal glasses arise from a competition between a slowing down of structural relaxation, because of partic...

Using both instantaneous snapshots and simulation generated scattering data, the steady-state ̄ ow behaviour of a concentrated aggregated colloidal suspension is analysed in terms of its structure factor S(k). We ® nd that in the shear thinning regime, unlike model hard sphere results, S(k) exhibits pre-peaks at small k, which we interpret as indicative of intermediate range order in the shear i...

We study optimal control problems of systems describing the flow of incompressible shearthinning fluids. Taking advantage of regularity properties of the flows, we derive necessary optimality conditions under a restriction on the optimal control.

The validity of potential flow analogy by the Hele-Shaw flow of non-Newtonian fluids is examined through experiments using two shear-thinning elastic polymer solutions for three different flow configurations, i.e. flows around a circular cylinder and a square cylinder and flows through an abruptly converging-diverging channel (slit). Although the polymer solutions are highly shear-thinning and ...

In this study, we use micro-particle image velocimetry (μ-PIV) and adapt a commercial birefringence microscopy system for making full-field, quantitative measurements of flow-induced birefringence (FIB) for the purpose of microfluidic, opticalrheometry of two worm-like micellar solutions. In combination with conventional rheometric techniques, we use our microfluidic rheometer to study the prop...

Some cultivars of grapevine have very compact cluster which adversely affect its quality and marketability. ‘Yaghouti’ is a commercial early table grape cultivar that has very compact clusters. The present study was conducted to assess the effects of mechanical and chemical thinning as well as GA3 application on cluster morphology and berry size of grapevine cv. ‘Yaghouti’. Treatments were chem...