With the collaboration of Iran Polymer Society

Document Type : Original research

Authors

1 Faculty of Chemical Engineering, Sahand University of Technology, Sahand New Town, Tabriz, Post box: 51335/1996, Iran

2 Membrane Technology Research Center, Sahand University of Technology, Sahand New Town, Tabriz, Post box: 51335/1996, Iran

3 Faculty of Polymer Engineering, Sahand University of Technology, Sahand New Town, Tabriz, Post box: 51335/1996, Iran

4 Department of Chemical Engineering, University of Bonab, Bonab, Iran

Abstract

In the current study, the flow field and morphology development of a polyethylene (PE) and ethylene vinyl acetate (EVA) blend were investigated numerically during extrusion through a spinneret using Fluent 6.3.26 software. The interface of the two phases was tracked using the volume of fluid (VOF) method. In a conventional spinneret, EVA droplets near the walls break up due to the high shear rate, while the central droplet deforms without breaking up. To enhance the breakup of EVA droplets, the effects of device geometry, including the spinneret angle and the presence of one or two lamps, were investigated in detail. The numerical results indicated that a decrease in the spinneret angle from 60° to 45° causes the central droplet to become more elongated in the flow direction. Additionally, the results showed that the presence of one or two lamps in the conical zone of the spinneret causes a portion of the central droplet to break up.

Graphical Abstract

CFD study of PE/EVA blend morphology development in a spinneret by Volume of Fluid method

Keywords

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