Optimization of conditions for an enhancement of thermal conductivity and minimization of viscosity of ethylene glycol based Fe3O4 nanofluid

Present study deals with experimental measurement of thermal conductivity and viscosity of Fe3O4 ethylene glycol nanofluid and multi-response optimization of conditions for maximum thermal conductivity and minimum viscosity of nanofluid. The thermal conductivity and viscosity were measured at 0.2, 0.5 and 0.8 vol% of concentration, 20, 50 and 80 degrees C temperature and 1, 2.5 and 4 h of ultrasonication time. Response surface methodology was employed to evaluate linear, quadratic and interactive effects of response variables. The multi response optimization yields the conditions: concentration 0.8 vol%, temperature 80 degrees C and ultrasonication time of 3.6 h. The optimum values of thermal conductivity and viscosity were 0.702 W/m K and 3.14 mPa s respectively and experimental values of thermal conductivity and viscosity were 0.694 W/m K and 3.10 mPa s with composite desirability (D) equal to 0.993. (C) 2016 Elsevier Ltd. All rights reserved.