Bidisperse Mixtures Of Particles Research Articles

Shear-driven density segregation: an experimental study

Granular materials can segregate spontaneously due to differences in particle properties when subjected to vibrations, shear strain or because of the equipment geometries. Although the difference in particle size is the most critical factor that drives segregation, the effects of large density difference may also be detrimental for a lot of industries. In this work, we experimentally investigate density-driven segregation in bi-disperse mixtures of particles having the same size but different density when subjected to non-uniform shear rates. We found that the features of the segregation process are related to the density ratio as well as to the dimensionless loaded mass. The experimental outcomes are then compared with the solution of a simple density-driven segregation model. The model can successfully capture the main features of segregation driven by density for a range of density ratios.

Spouting of Bidisperse Mixture of Particles: A CFD and Experimental Study

Many spouted bed applications involve mixtures of particles of different sizes, shapes, or densities. Depending on the characteristics of the particle mixture, undesirable phenomena such as particle segregation may occur, mainly due to differences in terminal velocities. Thus, a better understanding of the fluid dynamics of particle mixtures is still needed in this field. In this work, experiments and computational simulations were performed to analyze some aspects of the fluid dynamics of segregation patterns in conical spouted beds with binary mixtures. The simulated results are consistent with experimental data and can be used to predict regions of particle mixing or segregation in spouted beds.

Statistical model of collisions of bidisperse particles in an anisotropic turbulent flow

A statistical model for describing the motion and collisions of a bidisperse mixture of particles in anisotropic turbulent flows is presented. The model is based on a kinetic equation for the particle velocity probability density function (PDF). The results are compared with the data of a direct numerical simulation of the sedimentation of a bidisperse mixture of particles under the action of the gravity force.

Capabilities and limitations of laser doppler anemometers in studying heterogeneous flows with solid bidisperse particles

We consider some methodological problems connected with measurements of the velocities of large bidisperse particles when using laser Doppler anemometers (LDA's). We present the results of test measurements of the velocity distributions of different bidisperse mixtures of particles, required for LDA studies of heterogeneous flows.