Combined viscoelastic and elastic wave dissipation mechanism at low velocity impact

Abstract

The understanding of effects occurring during low velocity normal particle impact on a hard elastic plate is important for the description of different processes occurring during pneumatic conveying, in jet mills, mixers, or fluidized bed apparatuses. In this study, a suitable semi-empiric method is proposed to calculate the coefficient of restitution. This coefficient of restitution is modelled by means of combination of two different approaches. The first approach is based on dissipation of impact energy due to bending wave excitation in the plate described only by one inelasticity parameter. The second approach is based on viscoelastic mechanism of energy dissipation, represented by an additional viscoelastic damping coefficient. Thus, these two coefficients are responsible for bending and viscoelastic energy dissipation and are calculated independently from each other. The summarized energy dissipation is used to determine both material parameters and coefficients. A good agreement between calculated and measured coefficient of restitution was observed. In this way, the interaction between steel spheres impacting on glass plates with a thickness comparable to the diameter of the sphere was calculated as an example.