Journal of Non-Newtonian Fluid Mechanics, Vol.121, No.2-3, 157-162, 2004
Transient solutions of the dynamics in film blowing processes
The transient behavior and stability of film blowing have been investigated solving the governing equations consisting of the moving-boundary partial differential equations. Incorporating an orthogonal collocation on finite elements and a coordinate transformation, a new numerical scheme was devised to obtain previously unavailable transient solutions. The scheme overcomes severe numerical problems, that are encountered especially when the process is in a periodic oscillation called draw resonance. These simulation results provide, for the first time, temporal pictures which are close to those observed experimentally, and enable a systematic analysis of the process as regards its stability, multiplicity, sensitivity and stabilization strategies. (C) 2004 Elsevier B.V. All rights reserved.
Keywords:coordinate transformation;draw resonance;film blowing;linear stability analysis;multiplicity of steady states;orthogonal collocation;transient response;stability diagram