Stability of viscoelastic dynamic contact lines: An experimental study
- Department of Chemical Engineering, Stanford University, Stanford, California 94305 (United States)
An experimental study of the rivulet instability associated with spin coating a circular drop of fluid is conducted to examine the effect of elasticity on the onset and evolution of the instability. The spin coating experiments are conducted with viscoelastic drops consisting of a high molecular weight polystyrene in tricresyl phosphate (TCP), as well as the Newtonian solvent TCP. Results show an unequivocal delay in the onset of the instability when the appropriate Weissenberg number is sufficiently large, resulting in a larger coated area and more finger arms relative to Newtonian results. Experiments performed with the viscoelastic fluid at low Weissenberg number exhibit similar behavior to those performed with the Newtonian solvent as expected. Additionally, the growth rate of the instability is reduced for experiments in which the elastic forces are important, in agreement with the perturbation theory of Spaid and Homsy [Phys. Fluids {bold 8}, 460 (1996)], demonstrating that elastic forces have a stabilizing influence on the contact line instability. {copyright} {ital 1997 American Institute of Physics.}
- DOE Contract Number:
- FG03-87ER13673
- OSTI ID:
- 495864
- Journal Information:
- Physics of Fluids (1994), Vol. 9, Issue 4; Other Information: PBD: Apr 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
Stability of Newtonian and viscoelastic dynamic contact lines
Extensional viscosity and birefringence measurements of viscoelastic polymer solutions in filament stretching flows