Experimental Investigation of Thermal Conductivity and Effusivity of Ferrite Based Nanofluids under Magnetic Field

Abstract

We investigate the effect of magnetic field ( H ) on the thermal conductivity ( λ ) and effusivity ( ε ) of cobalt ferrite based nanofluids having different concentrations ( ϕ ). Cobalt ferrite nanoparticles (NPs) have been synthesized using the microwave assisted method. At high volume fraction of cobalt ferrite nanoparticles in water ( ϕ > 0), both thermal parameters have been found to be suppressed relative to ϕ and λ of water in the absence of H . However, it is seen that percentage values of the effusivity in perpendicular field direction show negative to positive variation, and thermal conductivity in parallel field direction shows negative to zero variation.