Effect of wall rougheners on cross-sectional flow characteristics for non-spherical particles in a horizontal rotating cylinder

Discrete-element-method(DEM) simulations have been performed to investigate the cross-sectional flow of non-spherical particles in horizontal rotating cylinders with and without wall rougheners. The nonspherical particles were modeled using the three-dimensional super-quadric equation. The influence of wall rougheners on flow behavior of grains was studied for increasing particle blockiness. Moreover,for approximately cubic particles(squareness parameters [555]), the rotational speed, gravitational acceleration and particle size were altered to investigate the effect of wall rougheners under a range of operating conditions. For spherical and near-spherical particles(approximately up to the squareness parameters [344]), wall rougheners are necessary to prevent slippage of the bed against the cylinder wall. For highly cubic particle geometries(squareness parameters larger than [344]), wall rougheners resulted in a counter-intuitive decrease in the angle of repose of the bed. In addition, wall rougheners employed in this study were demonstrated to have a higher impact on bed dynamics at higher rotational speeds and lower gravitational accelerations. Nevertheless, using wall rougheners had a comparatively small influence on particle-flow characteristics for a bed composed of finer grains.