(338f) Quantitative Validation for Frictional Granular Flows

Granular flows in which shearing plays a key role are prevalent in natural and industrial flows and understanding their behavior and flow characteristics is of considerable importance.  Because of their non-linear characteristics, and the general challenges in characterizing and describing multiphase granular flows, it has been difficult to develop models for and to simulate their flow behavior.  Experimental studies have frequently been employed to develop a better understanding of their behavior and to both guide and develop theoretical and computational models for them. Building upon our previous validation studies of collisional granular flows, here we focus on flows where friction plays a more significant role. We quantitatively validate DEM simulations with experimental measurements obtained from an annular shear cell and hopper devices to understand the impact of different frictional force models and material properties used in our validation tests on granular shearing flows.  In general, the frictional force models range from pragmatic linear techniques to rigorously more complex (nonlinear) contact mechanics inspired routines.  Computationally, we examine both ends of the spectrum to compare with the experimental measurements.