Plastic contact mechanics and its impact on DEM simulations of solds transport in extruders

Research work using the Distinct Element Method (DEM) has identified the potential of a discrete approach for more accurately modeling the motion of plastics solids within a single-screw extruder. Experiments of HDPE particles contacting a steel anvil showed a velocity dependency in their impact behavior, which becomes an important consideration when selecting an appropriate force-displacement model for DEM simulations. In addition, Experimental trials have been conducted to examine the bulk motion of solids within an actual singlescrew extruder at different screw speeds and barrel temperatures. The implications of velocity-dependency in the contact-displacement models were subsequently examined in 3-D, non-isothermal DEM simulations of the solids-inflow and solids-conveying zones of a single-screw extruder.