Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
670971 | Journal of Non-Newtonian Fluid Mechanics | 2010 | 19 Pages |
The cross-stream migration of a circular particles (or infinitely long cylinder) in two dimensional, inertia-less viscoelastic pressure-driven flows is examined through complementary finite element simulations and second-order fluid perturbation analyses for small Deborah number (De), where De is defined as the fluid relaxation time divided by the characteristic flow time. A neutrally buoyant, freely suspended particle migrates toward the center of the channel for all particle sizes and cross-stream positions due to the coupled effects of the linear and quadratic variations of the imposed velocity. A particle that is held at a fixed position, in contrast, experiences a cross-stream force directed toward the wall as a result of the coupled effects of the local shear flow and the flow relative to the particle.