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

Abstract

We investigate the effect of magnetic field ( ) on the thermal conductivity ( ) and effusivity ( ) of cobalt ferrite based nanofluids having different concentrations ( ). Cobalt ferrite nanoparticles (NPs) have been synthesized using the microwave assisted method. At high volume fraction of cobalt ferrite nanoparticles in water ( > 0), both thermal parameters have been found to be suppressed relative to and of water in the absence of . 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.

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