Simulations of pendant drop formation of a viscoelastic liquid

  • Davidson Malcolm R. (Department of Chemical and Biomolecular Engineering, The University of Melbourne) ;
  • Harvie Dalton J.E. (Department of Chemical and Biomolecular Engineering, The University of Melbourne) ;
  • Cooper-White Justin J. (Department of Chemical Engineering, The University of Queensland St. Lucia)
  • Published : 2006.06.01

Abstract

A modified Volume-of-Fluid (VOF) numerical method is used to predict the dynamics of a liquid drop of a low viscosity dilute polymer solution, forming in air from a circular nozzle. Viscoelastic effects are rep-resented using an Oldroyd-B model. Predicted drop shapes are compared with experimental observations. The main features, including the timing of the shape evolution and the 'bead-on-a-string' effect, are well reproduced by the simulations. The results confirm published conclusions of the third author, that the deformation is effectively Newtonian until near the time of Newtonian pinch-off and that the elastic stress becomes large in the pinch region due to the higher extensional flow there.

Keywords

References

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