The vortex growth of a K.B.K.Z. fluid in an abrupt contraction
A constitutive equation of the K.B.K.Z. type is used to describe the flow behavior of LDPE melts in abrupt contractions. The numerical algorithm is the finite element method based on a fixed mesh while the strain history is calculated along streamlines. It is shown that the calculations based on the K.B.K.Z. model do predict the occurrence of vortices at relatively low values of the Weissenberg number, which in general is not the case with other less realistic models.
constitutive equation of the K.B.K.Z. type
scientific article; zbMATH DE number 4091004