Hybrid nanofluids has been attracted lots of attention due to simultaneous take advantage
of the properties of two or more kinds of nanoparticles in the base fluid.
Carbon Nanotubes (CNTs) are utilized widely attached to metal oxide nanoparticles
due to significant thermal characteristics. This study aims to assess experimentally the
thermal conductivity of the hybrid nanofluid of Zinc Oxide (ZnO) and Multi-Wall CNT
(MWCNT) in Engine oil (SAE 10W40). The influences of nanoparticles concentration as
well as fluid’s temperature are evaluated. The experiments performed at the temperature
between 25 oC and 50 oC and nanoparticles volume fraction from 0.05 to 0.8 %. The
experimental results showed that a higher ratio of nano-lubricant thermal conductivity
is achieved for a higher volume fraction and temperature of nanoparticles. According
to the absence of an exact relationship to determine the thermal conductivity of ZnOMWCNT/
Engine oil, a correlation is developed based on the test measurements presented
in terms of volume fraction and temperature using a curve-fitting method. A deviation analysis is also performed on the ratio of thermal conductivity achieved from the
developed correlation and experimental data showing a reasonable agreement