x
Diese Website verwendet Cookies. Mit der Nutzung der Website stimmen Sie deren Verwendung zu. Weitere Informationen erhalten Sie in unserer Datenschutzerklärung.

Simulation of charge and structure behaviour in a tumbling mill

For a long time discrete element methods (DEM) has been used as simulation tools to gain insight into particulate flow processes. Such a process may be grinding in tumbling mills, where the mechanical behaviour is complex. To include all phenomena that occur in a mill in a single numerical model is today not possible. Therefore, a common approach is to model milling charges using the DEM assuming a rigid mill structure. To close the gap between reality and numerical models in milling, more physically realistic methods must be used. In this work, the finite element method (FEM) and the smoothed particle hydrodynamic (SPH) method are used together to model a ball mill charge in a tumbling mill. The mesh free formulation and the adaptive nature of the SPH method result in a method that handles extremely large deformations and thereby suits for modelling of grinding charges. The mill structure consists of rubber lifter and liners and a mantel made of solid steel. It is modelled with the finite element method. For the elastic behaviour of the rubber, a Blatz-Ko hyper-elastic model is used. The supplier of the lining provided experimental data for the rubber. The deflection profile of the lifters obtained from SPH-FEM simulation shows a reasonably good correspondence to pilot mill measurements as measured by an embedded strain gauge sensor. This computational model makes it possible to predict charge pressure and shear stresses within the charge. It is also possible to predict contact forces for varying mill dimensions and liner combinations.