Improvement in techniques to determine extensional rheology from entrance flows: Computational and experimental analysis

Abstract

Flow through an abrupt contraction has been analyzed experimentally and theoretically through FEM simulations using the modified White-Metzner model. The results show that the 'entrance viscosity' (entrance pressure drop divided by the shear rate) strongly depends on the shape of the steady extensional viscosity, the L/D ratio of the orifice die, and it can be properly described by the newly proposed model.