Experimental Study of Rheological Behavior of MWCNT-Al(2)O(3)/SAE50 Hybrid Nanofluid to Provide the Best Nano-lubrication Conditions

In this study, MWCNT-Al(2)O(3) hybrid nanoparticles with a composition ratio of 50:50 in SAE50 base oil are used. This paper aims to describe the rheological behavior of hybrid nanofluid based on temperature, shear rate ([Formula: see text] and volume fraction of nanoparticles ([Formula: see text] ) to present an experimental correlation model. Flowmetric methods confirm the non-Newtonian behavior of the hybrid nanofluid. The highest increase and decrease in viscosity ([Formula: see text] ) in the studied conditions are measured as 24% and − 17%, respectively. To predict the experimental data, the five-point-three-variable model is used in the response surface methodology with a coefficient of determination of 0.9979. Margin deviation (MOD) of the data is determined to be within the permissible limit of − 4.66% < MOD < 5.25%. Sensitivity analysis shows that with a 10% increase in [Formula: see text] at [Formula: see text] 1%, the highest increase in [Formula: see text] of 34.92% is obtained.