The simulation of viscoelastic flow past a sphere, or a sedimenting sphere, has attracted considerableinterest since being established as a benchmark problem in computational flow dynamics [23]. As a
geometry exhibiting both shearing and extensional flows, the sedimenting sphere design has the potential
to probe properties of viscoelastic fluids under various conditions. In particular, we explore the low
Reynolds, high Weissenberg number flow regime, in which elastic forces dominate. Using OpenFOAM,
an open-source computational fluid dynamics software, we are able to implement immersed boundary
conditions so that we can demonstrate unsteady startup in addition to steady-state dynamics. We find
that these conditions as specified are currently unstable for reasonable sphere densities under typical
gravitational acceleration, and therefore opt for unrealistically high densities and reduced accelerations
(see Table 1). Nonetheless, we are able to capture realistic steady-state conditions, which we compare to
the Faxen wall correction. We find that our boundary conditions, described in section 2, perform better
than the Faxen correction for certain geometries. In future research, we hope to stabilize our startup
dynamics for reasonable sphere densities and gravitational acceleration.