Ductile behavior and heat transfer efficiency in polymer extrusion by self-controlled “flipping melt-pancakes” with multi-fields synergy

Abstract

A new design approach of “Flipping Melt-Pancakes” structure was proposed to improve the ductile behavior and heat transfer capacity for polymer melt extrusion. Three-dimensional numerical analysis of novel proposed structures was implemented compared with Maddock element and conventional screw that are commonly used in industry. Results indicated that flow patterns of polymer fluid affected by the screw configurations, inducing different ductile deformation, i.e., shear deformation occurred in Maddock channel and torsional deformation yielded in the “Flipping Melt-Pancakes” structure. Deformation flow patterns can contribute to radial mass transfer, achieving effective exchange of local heat and making temperature distribution more uniform. Besides, the change of velocity direction brought by the circumferential movement facilitated the synergy between velocity and temperature gradient and, improved heat transfer. The novel proposed structure based on the polymeric multi-fields synergy principle- “Flipping Melt-Pancakes” structure- has good heat transfer properties, low pressure loss and good synergy effect, reflecting that the field synergy principle can be applied to optimize the screw structures in polymer processing. It provides a new theoretical perspective to solve the increasingly severe challenges due to the insufficient control of mass transfer and heat management in plasticization process of extrusion or injection.