The behaviors of particle-wall collision for non-spherical particles: Experimental investigation

The particle-wall collision behavior for non-spherical particles has significant effects on gas-solid separation, which is important in mechanical, energy and other industries. Particle-wall collision experiments of spherical and non-spherical glass particles with polished and rough walls were conducted. The collision velocities were measured by high-speed photography, and the effects of particle sphericity and wall roughness were analyzed. The results show for large impact angles alpha(1), the restitution coefficient e is independent of alpha(1) and increases with increasing particle diameter. For the non-spherical particles or the rough wall, e increases when alpha(1) is small and the friction coefficient f increases with decreasing alpha(1). The non-spherical particles have smaller e, and larger f for small alpha(1). The roughwall has smaller e for large alpha(1) but greater dependence of e on alpha(1), resulting in larger e instead for alpha(1) -> 20 degrees. Under sliding condition, f increases with increasing wall roughness or decreasing particle diameter. (c) 2019 Elsevier B.V. All rights reserved.