Granular Shear Cell
(with varying innerwheel roughness)
An annular shear cell was fabricated to study the behavior of granular flows in a shear cell, where the rotating wheel has a prescribed roughness. As shown in Fig. 1, the granular shear cell (GSC) has an aluminum frame with a Plexiglas body so that the dynamic behavior of the granular flow can be observed. The wheel is attached to a 1/16 HP motor capable of achieving a constant rotational speed of approximately 53 to 222 RPM, which corresponds to a linear velocity of 0.55 m/s to 2.29 m/s. The wheel radius is 8.57 cm (3.375 in) and the distant from the center of the wheel to the stationary outer cylinder is 14 cm (5.625 in). Thus, the gap height H is approximately 5.43cm. The steel spheres (diameter = 4mm) fill up the gap with a solid fraction = 0.7, which means that 70% of the overall shear gap volume is filled with the steel spheres or “granules” during operation. 

