Comprehensive study of MWCNT and CuO/SAE50 hybrid nanofluid with experimental method and response surface methodology and introducing this nanofluid to the industry

Abstract

In this study, rheological behavior of hybrid nanofluid (HNF) with MWCNT(35%)-CuO (65%) nanoparticles (NPs) in SAE50 base oil was investigated by response surface methodology (RSM) and laboratory methods. Viscosity of HNF samples with solid volume fractions of SVF = 0.0625% to 1% was measured at temperatures between (T = 25–50 °C) and shear rates in the range of SR = 666.5–7998 s−1 using a Brookfield viscometer. The behavior of HNF shows non-Newtonian behavior in terms of relation between SR and shear stress (SS) in all SVFs. The relative viscosity at T = 30 °C and SVF = 1% has the highest value and is equal to + 22%. Viscosity changes in terms of temperature show that viscosity decreases with increasing temperature. The maximum viscosity difference at T = 25 °C is equal to −13.7 (-2.97). Also, to save time and reduce economic costs and check the accuracy and correctness of experimental data, it was predicted by RSM. Modeling with a three-variable mathematical relationship including T, SVF, and SR with R2 = 0.9986 coefficient was presented. After checking the viscosity with independent variables, it was determined that T effect is greater than other parameters on viscosity. Comparison results between experimental data and the proposed data show a high agreement between the predicted values.