NUMERICAL-SIMULATION OF HIGHLY VISCOELASTIC FLOWS THROUGH AN ABRUPT CONTRACTION

In a recent paper, Marchal and Crochet have proposed a new mixed algorithm for calculating viscoelastic flow. The coupling between velocity and stress components is solved by means of multiple bilinear stress sub-elements embedded in the Lagrangian element for the velocity field while streamline upwinding is used for solving the advection dominated constitutive equations. The paper reviews the motivation and the contents of the new method and explores in detail the flow of Oldroyd-B, Phan Thien-Tanner and Giesekus-Leonov fluids through a circular abrupt contraction. No limitation based on the value of the Weissenberg number has been found for the calculation of such flows. The sensitivity of the macroscopic flow features upon a variation of the material parameters is also investigated.