Influence of the uniform electric field on viscosity of magnetic nanofluid (Fe3O4-EG)

Viscosity of Fe3O4/ethylene glycol nanofluids under electric field (ac and dc) was investigated experimentally. Magnetic nanofluids were prepared by dispersing Fe3O4 nanoparticles in ethylene glycol using a sonicator. Experiments showed that dilute magnetic nanofluids (<0.05 vol. %) as well as base fluid exhibit Newtonian behavior. Viscosity of Fe3O4/ethylene glycol nanofluids in electric field was measured using capillary tube viscometer. Electric field decreased the viscosity of magnetic nanofluids and base fluid. The viscosity reduction was more profound in higher volume concentrations of nanoparticles. dc electric field caused greater viscosity reduction in magnetic nanofluids relative to ac electric field while ac electric field showed greater reduction effect for base liquid. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4763469]