Berg, J.B. and Bokhove, O. and Peletier, M. and Williams, J.F. and Zwart, H. (2000) Thermal Modeling in Polymer Extrusion. [Study Group Report]
|
PDF
4MB |
Abstract
In this paper we consider thermal effects of polymer flows through a cylindrical die. First, we derive a model for the oscillatory behavior of polymer flow in an extruder given a functional relation between the pressure and flow rate. A simple isothermal but temperature dependent model is constructed to find this relation. Unfortunately, the model is shown to be invalid in the physical regime of interest. We present several arguments to suggest that the isothermal assumption is reasonable but that a more detailed understanding of the small-scale molecular dynamics near the boundary may be required. Second, we show that a simplified model for thermoflow multiplicity in a cooled tube is inconsistent, when the stationary non-Newtonian flow is assumed to be incompressible without radial pressure gradients and without radial velocity. This inconsistency can be removed by allowing for weak compressibility effects in the down-steam area.
Item Type: | Study Group Report |
---|---|
Problem Sectors: | Materials |
Study Groups: | European Study Group with Industry > ESGI 39 (Twente, Netherlands, Oct 9-13, 2000) (SWI 2000) |
ID Code: | 385 |
Deposited By: | Dr Kamel Bentahar |
Deposited On: | 26 Nov 2011 20:29 |
Last Modified: | 29 May 2015 20:00 |
Repository Staff Only: item control page