Simultaneous effects of MWCNT and SiO2 on the rheological behavior of cooling oil and sensitivity analysis

Mousa Rejvani; Alireza Heidari; Seyfolah Seadodin

doi:10.1016/j.heliyon.2023.e12942

Simultaneous effects of MWCNT and SiO2 on the rheological behavior of cooling oil and sensitivity analysis

Heliyon. 2023 Jan 12;9(2):e12942. doi: 10.1016/j.heliyon.2023.e12942. eCollection 2023 Feb.

Authors

Mousa Rejvani¹, Alireza Heidari², Seyfolah Seadodin¹

Affiliations

¹ Department of Mechanical Engineering, Semnan University, Semnan, Iran.
² Department of Mechanical Engineering, Damghan University, Damghan, Iran.

Abstract

Many scholars are attracted to nano-lubricants due to their unique properties. In the present study, the rheological behavior of a new generation of lubricants has been investigated. SiO₂ nanoparticles with an average diameter of 20-30 nm along with MWCNT with an internal diameter of 3-5 nm and the external diameter of 5-15 nm has been dispersed in 10W40 engine oil as base-lubricant and MWCNTs-SiO2 (20%-80%)/10W40 hybrid nano-lubricant has been produced. Nano-lubricant behavior agrees with the Herschel-Bulkley model and is of Bingham pseudo-plastic type below $55 ° C$ . Also, in the temperature of $55 ° C$ , nano-lubricant behavior has changed to Bingham dilatant. The viscosity is increased by 32% in the proposed nano-lubricant compared to base lubricant (Dynamics Viscosity Enhancement). Finally, a new correlation with a precision index of R-squared >0.9800, Adj. R-squared >0.9800, and the maximum margin of deviation of 2.72% has been presented, increasing the applicability of this nano-lubricant. Eventually, the sensitivity analysis of nano-lubricant has been conducted, studying the comparative effect of volume fraction and temperature on viscosity.

Keywords: Characterization; Hybrid nano-lubricants; Nanofluid; RSM Modeling; Sensitivity; Viscosity.