Monitoring Polymer Melt Process with Electrical Capacitance Tomography

H. Wanga, Y. Lib, G. Qiua, P. Lingc, W. Yangd

a Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, China

b. Department of Chemical Engineering & Biotechnology, University of Cambridge, UK c Shaanxi Shenmu red Liulin Mining Group Co. Ltd.,Shenmu, China

d School of Electrical and Electronic Engineering, University of Manchester, UK

Abstract

Accurate and reliable measurement of the polymer melt temperature can improve the operation efficiency and lead to the improved design of processing equipment and control for moulded products. Although different techniques, such as thermocouple wire mesh and infrared probe, have been employed to measure the temperature, there is no suitable means so far to measure the temperature distribution in 2-D in a polymer extrusion process without disturbing the melt flow. Electrical Capacitance Tomography (ECT) is a non-intrusive and non-invasive technique to obtain permittivity distribution of a cross section. This paper gives the preliminary test results with an ECT sensor for polymer melt process. Eight electrodes were mounted outside of the ceramic tube, which was used to heat and melt the polymer powder. A permittivity profile with time and reconstructed images of the melt process are given and analyzed.

Keywords: Polymer Powder, Melting, Capacitance Tomography, Temperature