Analyzing mixing behavior in a double paddle blender containing two types of non-spherical particles through discrete element method (DEM) and response surface method (RSM)

Abstract

The discrete element method (DEM) and experiments were used to examine the mixing mechanisms and flow patterns in a twin-paddle blender containing two types of non-spherical particles. The applicability of the GPU-based DEM model was demonstrated through calibration tests using a classical rotary drum. Afterward, the calibrated DEM model was utilized to investigate the impact of factors such as the vessel fill level, paddle rotational speed, and particle number ratio on mixing performance. The relation between mixing performance and the operational parameters was predicted using the Response Surface Method (RSM). An escalation in the fill level, coupled with a reduction in impeller speed, led to a rise in the overall number of particles that came into contact with one another, suggesting an increase in the compactness of the mixture. The computed Peclet numbers and diffusivity coefficients revealed that diffusion was the prevailing mixing mechanism.