Experimental investigation on thermal properties of silver nanofluids

摘要

This paper reports on an experimental investigation of the thermal properties behavior of 0.5 wt% silver nanoparticle-based nanofluids (NF) containing oleic acid (OA) and potassium oleate surfactant (OAK) with concentrations of 0.5, 1, and 1.5 wt% respectively. The experiments were conducted from 20 degrees C to 80 degrees C. It was shown that the NF with 1 wt% OAK(+) yielded the highest thermal behavior enhancement of about 28% at 80 degrees C compared to deionized water. The thermal performance had higher than the base fluidanofluids at approximately 80%. Moreover, the NF containing OAK(+) showed higher thermal conductivity and dynamics of specific heat capacity than deionized water in all of the experimental conditions in this study. The rheological experiment showed that viscosity of NF was significantly dependant on temperature. As shear rate increased, the shear stress of the NF increased; however, the viscosity of the nanofluids decreased first and then stabilized. It was further found that NF containing OAK(+) at a range of operating temperatures produced Newtonian behavior. (C) 2015 Elsevier Inc. All rights reserved.