A Simple Model of the Melt Fracture Instability
نویسنده
چکیده
In this note we develop and analyze a system of equations describing a molten linear polymer being extruded in a capillary rheometer which is operating under the controlled condition that the mean velocity at the capillary inlet is maintained at a constant value. Slipping of the melt at the pipe wall is permitted and an evolution equation for the boundary slip parameter is postulated. The combined system governing the mean cross-sectional velocity and slip parameter is shown to exhibit relaxation oscillations similar to those observed in actual rheometers.
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