Mixing Patterns Obtained in An Oscillatory Shear Mixer

Even though there is a great amount of study of granular material, there still exists a great deal of interest in understanding concentrated granular flow because of its strong effect in the achievement of homogeneous granular mixing. Considering this emblematic problem in granular behavior, this work focused on developing a simple system where the imposed rate of strain was varied following a periodic function which permits to study the granular material random movement and the mixing of granular material at different wall amplitudes. The goal was to gain insights of the physical phenomena involved in the 3-dimensional granular flow using real powders with polydispersity on size. Results expose the presence of chaotic mixing in the superficial layer and are strongly related to the wall amplitude and particle size. The effect of the chaotic pattern is increased when increasing the velocity of the moving walls.