Mixing Performances of Typical Screw Elements in Buss Kneader

In the present study, the flow and mixing characters of the typical screw elements in the re- ciprocating pin single-screw extruder were studied using a Polyflow finite element package. Based on the statistical treatment of the flow trajectories for a large number of the mass points which were located at the entrance of the screw element, the dynamic mixing process was analyzed. Furthermore, the distri- bution index and the segregation scale were applied to evaluate the distribution mixing and the dispersive mixing, respectively. At last, the effects of the operating conditions, material viscosity and the pins on the mixing performances of the extruder were also analyzed. Some of the numerical results were com- pared with previous results.