Energy dissipation during the impact of steel ball with liner in a tumbling ball mill

Abstract

The coefficient of restitution and the energy dissipation during the impact of the steel ball with liner in a tumbling ball mill was addressed. Critical speed ranged from 76 to 88% was concerned, and numerical solution using the finite element method for steel ball impacting with liner was investigated. Results indicated that the coefficient of restitution and impulse ratio increase in proportion to the critical speed increasing. Moreover, the contact force-displacement response is obtained and divided into two stages: elastic-plastic compression stage and elastic restitution stage. By representing the energy dissipation during collision, the encompassed area by the elastic-plastic compression stage and the elastic restitution stage decreases with the critical speed increasing. Finally, the kinetic energy loss ratio is given to quantitative represent the energy dissipation. It is shown that the kinetic energy loss ratio is inversely proportional to the critical speed.

Mathematical modeling and optimization of spiral drum screen in the concrete residue recovery system

“…When the distance between point A and point D is less than the diameter of the material, the material rising from point A will collide with the material falling from point C. In order to avoid energy loss caused by material collision in parabolic motion, material diameter must be less than 2 times of curvature radius of parabolic vertex. 20 By using the curvature radius formula, it can be obtained that the curvature radius of any point on the parabolic trajectory as shown in equation (5) is …”