Use of powder rheometry as a DEM calibration tool

Discrete element modelling (DEM) is a powerful tool to predict the behavior of granular materials in industrial operation. However, DEM requires a full definition of particulate material properties to be used in the calculation. The Anton Paar Powder Cell rheometer with its different impellers geometries allow to provide different experimental conditions in which the different mechanical properties play a different role so that they can be independently set. In this project the experimental tool is the state of the art Powder Cell purposely developed by Anton Paar Company to fit on an Anton Paar rheometer and to carry out torque measurements on both aerated and fluidized powders. This instrument is able to carry out torque measurements with different impeller geometries, speed, position and aeration rate. The different kind of impeller used in this research are flat impellers with two heights of 5 and 10 mm, a cylindrical impeller and a circular impeller. These impellers were used to measure the torque value of glass beads with nominal size of 2 and 4 mm. at different rotational speeds. The same conditions were used for the simulation of torque values with EDEM commercial software. Simulation were carried on with the different impellers geometries and rotational speeds in order to have conditions in which the different material properties came into play singularly in a limited number. This could enable us to provide a sequence of experimental conditions to fully characterize the best material parameters to be used in the in DEM modelling in more general and different applications.