Modelling of a conveying zone of a corotating twin screw extruder based on the local residence time distribution

Mathilde Mercier (1) , Sandrine Hoppe (2) , Thierry Vivier , Guo-Hua Hu (2) , Fernand Pla (1)

1 LSGC - Laboratoire des Sciences du Génie Chimique
2 LRGP - Laboratoire Réactions et Génie des Procédés

This work gives an access to local Residence Time Distribution (RTD) in a twin-screw extruder and is concerned by the elaboration of a model for a conveying zone and a study of the melting zone. An in-line fluorescence monitoring device has been designed to determine local RTD functions along a co-rotating twin screw extruder. The sensor used can be mounted at various locations in the barrel. Experiments were carried out to validate this system. The convolution theory enables to determine the RTD functions of independent sections of the extruder. This mathematical device gives an access to local zones such as melting areas despite some measurement difficulties. Then, a predictive model of conveying screw elements is developed based on the flow in individual screw elements and the theory of convolution. First, the conveying zone is divided into independent elements to be defined. Second, the flow inside the channel is supposed to be the same as in a parallel plate model. Then, the model is achieved by the statistical superposition of the individual RTDs. Finally, another interesting use of the fluorescent signal is to correlate it with the melting state and the temperature of the polymer in the melting zone.

Domaines: Polymères; Génie des procédés; Matériaux

Mathilde Mercier, Sandrine Hoppe, Thierry Vivier, Guo-Hua Hu, Fernand Pla. Modelling of a conveying zone of a corotating twin screw extruder based on the local residence time distribution. 18th Annual Meeting of the Polymer Processing Society, Jun 2002, Guimarães, Portugal. ⟨hal-02521860⟩