Sommaire:

The measurement of extensional viscosity of non-Newtonian fluids has been an area of activity for several decades. While it is in principle simple to impose a controlled shear deformation on a liquid, it is not so simple to produce a controlled extensional deformation.
This presentation will demonstrate the application of the so-called Filament Stretching Rheometer for the implementation of well controlled extensional flow. The attainment of steady flow will be shown. In addition the relaxation of stress after a defined deformation for polymeric liquids will be illustrated.

Finally the presentation will discuss instabilities that may occur in extension. These include instability at the plates and what appears to be a cohesive fracture in liquids.

Pour plus d'informations, merci de contacter Gross M.