Numerical and experimental investigation on flow of polymer in extrusion die
Loading...
Date
2019-07
Authors
Nuraina Nabilah Binti Idris
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
This study is conducted to investigate the rheology of the polymer melt in the extrusion die and the best processing conditions to minize the extrudate swell. It can be determined through a series of process which consist of melt flow index(MFI) testing, numerical analysis using ANSYS Fluent Software and the extrusion process. From the MFI testing, it was found that the MFI value increases when the temperature is increases as well as the load applied increases. However, when the highest 15 kg load was applied the MFI value decreased. The apparent viscosity decreased when the temperature increased as well as the load applied. The polymer exhibits the pseudoplastic behaviour as the temperature increases since the power law index is less than 1. Simulation of the die swell ratio at 115°C melting temperature and screw speed 30 rpm is the lowest followed by melting temperature at 135°C and screw speed of 70 rpm and at 125°C and 30 rpm contributes to the highest die swell ratio. The best processing condition which contributes to the lowest die swell ratio obtained from the experimental is observed at melting temperature 125°C and screw speed of 30 rpm. The difference of the die swell ratio between the experimental and simulation investigation indicates that the numerical analysis is unable to meet the agreement of the real-world factors as the simulation do not have any external factor such as surrounding temperature to be considered.