NUMERICAL-SIMULATION OF THE MOTION OF A SPHERE IN A BOGER FLUID

We use the finitely extensible non-linear elastic dumbbell theory deve loped by Chilcott and Rallison in order to analyze the flow of an inor ganic Boger fluid around a sphere for two ratios of the cylinder to sp here radii. We use four different sets of material parameters for desc ribing the same viscometric behavior of the fluid; we find important d ifferences in the drag dependence upon the Weissenberg number. In part icular, we examine the generation of recirculating vortices in the wak e of the sphere. We also calculate the effect of the second normal str ess difference upon the drag.