Shear granular flow of highly polydisperse disks

In this experimental project we study the shear flow of 2-D disk particles, using mechanical plungers to push the particles through a cross shaped canal. In this manner we can imitate the flow of amorphous solid particles with high polydispersity in various flow geometries.

We laser-cut disks of various radii ranging from 1.6 to 3.2 cm. We control the polydispersity by mixing together the disk sizes as required.

In particular, the mean affine flow does not depend much on the polydispersity, but individual particles move nonaffinely and the amount of that nonaffine motion depends on the particle size. We additionally quantify how these details relate to T1 events and particle rearrangements as the samples flow.