Draw resonance and kinematic waves in viscoelastic isothermal spinning

Draw resonance is one of the major instabilities in polymer processing. It is a hydrodynamic instability and not a viscoelastic one. The isothermal spinning of viscoelastic fluids is analyzed to derive the criterion for draw resonance agreeing with the results by the linear stability analysis. This criterion explains the mechanism of draw resonance as to how and why the oscillation starts and persists, as the drawdown ratio is increased beyond its critical value. Differences between viscoelastic and Newtonian fluids reveal that viscoelasticity delays the tension response of the system, rendering the tension less sensitive to make the system more stable.