Anisotropies in granular temperature in a dense sheared granular flow

We investigate a three-dimensional, slow, gravity-driven, sheared granular flow, making use of both simulation (carried out using the Discrete-Element Method) and experiment (using glass beads, imaged via an index-matched fluid). We begin by performing a quantitative comparison between the two procedures, concentrating on the level of agreement at the microscopic scale. After establishing how well the simulation can reproduce the microscopic fluctuations in particle velocities seen in experiment, we proceed to carry out a tensorial analysis of granular temperature. Our results show different types of behavior near the boundary and in the bulk of a granular flow, due to differences in the particle packing structure, and highlight anisotropies that may have implications for granular continuum modeling.