Simulating Sedimentaion of Two Large Solid Particles in a Confined Bingham Fluid

Sedimentation of two rigid circular solid particles aligned in the vertical direction at a distance from each other and freely falling in a Bingham fluid is numerically simulated using the OpenFOAM softaware. It is shown that a fluid’s yield stress strongly affects the settling of both particles in a non-trivial fashion. The numerical results shows that, in general, a fluid’s yield stress has a retarding effect on the particles motion. Interestingly, we predict that center of mass of the pair of particles move with a constant velocity at sufficiently large times. The shape and size of the plugs formed in the domain are also affected by the Bingham numbe.