Modeling Melt Conveying and Power-Consumption of Co-Rotating Twin-Screw Extruder Conveying Elements

Description

Fully intermeshing co-rotating twin-screw extruders are used for various applications ranging from polymer to food processing. This extruder type shows excellent mixing capability and conveying behavior, therefore, it perfectly suits for demanding applications in terms of homogeneity, gentle material processing and product quality. Tailoring the screw configuration and processing conditions to the material requires accurate prediction of conveying and power-consumption behavior. For this purpose, we present novel prediction models for double-flighted fully-intermeshing co-rotating conveying elements. These elements are the most common element type in co-rotating twin screw extruders, due to their conveying and mixing capabilities. Our isothermal Newtonian models are based on CFD-simulation data of the complex element geometry without simplifications. The subfactorial dataset of 772 design points spans a broad parameter range, including various screw pitches, diameter ratios, and screw and barrel clearances. Using this dataset, symbolic regression generated easy-to-use mathematical functions that include all the knowledge gained by the CFD-simulations. For the first time, it is possible to predict the conveying and power-consumption behavior of fully-intermeshing co-rotating conveying elements without any geometry simplifications and therefore achieve significantly higher accuracy at predicting the process performance. In other words, our models combine low application barrier of analytical models with high accuracy of CFD-simulations. Furthermore, included screw flight clearances allow significantly better predictions of the influences of wear on the conveying and power-consumption behavior, which helps in understanding the increasing power demand and possible material degradation due to screw wear.

Period	03 Oct 2024
Event title	European Regional Meeting of the Polymer Processing Society, PPS-2024
Event type	Conference
Location	SpainShow on map