title: Electrokinetic effects of charged nanoparticles in microfluidic Couette flow.
abstract: The behavior of Couette flow of nanofluids composed of negatively-charged nanoparticles dispersed in aqueous NaCl solutions is studied theoretically. The equation for calculating the Couette flow velocity profiles is derived. The induced electric fields and velocity profiles are calculated as a function of key parameters including nanoparticle size and volume fraction. We have found for the first time that the velocity profile of nanofluids containing charged nanoparticles deviates significantly from the classical linear velocity profile for Couette flow. This previously unseen flow phenomenon is attributed to the dominance of the electric field strength induced by the flow of charged nanoparticles. This new mechanism of nanoparticle-induced microfluidic transport could lead to novel microfluidic and tribological applications.
authors.affiliation: Mechanical and Industrial Engineering Department, University of Illinois at Chicago, 842 West Taylor Street, Chicago, IL 60607, USA. chulchoi@uic.edu
authors.forename: Chul Jin
authors.initials: CJ
authors.lastname: Choi
authors.forename: Seok Pil
authors.initials: SP
authors.lastname: Jang
authors.forename: Stephen U S
authors.initials: SU
authors.lastname: Choi
mesh_terms: D004573:Electrolytes / Q000737:chemistry; D007700:Kinetics; D046210:Microfluidic Analytical Techniques; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D012666:Semiconductors; D012965:Sodium Chloride / Q000737:chemistry; D013499:Surface Properties
chemical_list: D004573:Electrolytes; D012965:Sodium Chloride