DRAW RESONANCE IN FILM CASTING AS A RESPONSE PROBLEM USING A MATERIAL DESCRIPTION OF MOTION
W. S. Smith, and D. F. E. Stolle
A new numerical algorithm was developed for simulating one-dimensional, isothermal film casting of a viscoelastic polymer. The algorithm incorporates a material description of motion and allows the observation of draw resonance as a response problem. Simulation results for velocity, thickness, stress and stability for a low relaxation time agreed with the closed-form solutions for a viscous fluid. When the elastic contribution was increased the observed effects were as follows: the velocity decreased; the thickness gradient at the die increased; the thickness at the roll increased; the axial stress decreased; and the stability of the film decreased.