CFSeminar: Gaojin Li (Cornell University), "Electrophoresis in Viscoelastic Fluids"

• 12:00 PM until 1:15 PM 
• Tuesday, September 12, 2017, 12 pm, 116 Upson Hall (Refreshments)

Abstract:  Electrophoresis is the motion of suspended charged particles under electric field and has been widely used in bio-analysis and microfluidics. The particle is drifted due to the balance of three forces: the electric force, the drag and the retardation force due to the relative motion between the particle and its surrounding ion cloud of negative charges. So far, most previous studies are limited to the particle motion in a Newtonian fluid. In this study, we theoretically investigate the electrophoretic motion of charged particles in viscoelastic fluids under the assumption of small polymer concentration. The analysis show that at small Deborah number, the polymers breaks the front-and-aft symmetry of the flow field while does not affect the particle speed. At high Deborah number, polymers strongly stretch near the stagnation points of the particle and reduce the particle speed.