Fundamentals of plasticating extrusion. III. Development of a mathematical model

Abstract

This article describes a general mathematical model summarized in the form of a computer program for the plasticating extruder. The model combines features of the metering‐zone model previously published, the melting‐zone model described in paper No. I of this series, and a feed‐zone model based on an extension of known theories. It is based on theoretical models for each zone unified and improved by non‐linear estimation to accurately describe the extrusion experiments. The mathematical model predicts temperature, pressure, and melt channel width profiles of the plastic being processed in the plasticating extruder as a function of design and operating variables of the machine. It enables for the first time the design of the whole machine based on temperature and pressure profiles, including new combinations of cylindrical and tapered roots.

Rheological Behavior of Unvulcanized Rubber

“…A detailed theory relating the rheological and thermal properties of polymers to their screw extrusion characteristics has been developed. Integrated models of all three regions of the screw extruder have been developed and put in the form of digital computer programs by Klein et al [137,274] and later authors. Pigott [230] and Carley et al [53] applied this theory to the analysis of screw extruders.…”

A novel melting model for polymer extrusion: Mechanically induced transition layer removal

“…[35] In the same year, along with Tadmor, they proposed some modifications to the original melting model and developed software to estimate the profiles for melt temperature, melt pressure, and melting based on screw design and operating conditions. [36] Halmos and Pearson developed a melting model in 1976 considering the five regions identified in Maddock's experiments. It includes two more regions than the Tadmor melting model: the melt layer between the screw root and the solid bed, and the melt layer between the passive flank on flight and the solid bed.…”

“…[ 35 ] In the same year, along with Tadmor, they proposed some modifications to the original melting model and developed software to estimate the profiles for melt temperature, melt pressure, and melting based on screw design and operating conditions. [ 36 ]…”