Conclusions
In the past decade, filament rheometry has developed into a viable tool for measuring transient extensional viscosity of complex fluids.
Interaction of experimentation, simulation and molecular modeling!
- Good agreement with Brownian dynamics simulations, except at extremely high molecular weights (R. Larson, plenary paper).
Filament Stretching Extensional Rheometers (FISER)
- Impose a time scale
- Mechanically difficult (& expensive) to implement
Capillary Breakup Extensional Rheometers (CABER)
- Material selects its own time-scale for self-similar visco-elasto-capillary thinning:
- Easy to realize, but analysis is more complex:
- Timescales: capillary, elastic, mass transfer, heat transfer...
Future work: other classes of complex ‘Non-Newtonian’ fluids