Experimental analysis and comparison of thermophysical properties of the three different hybrid nano-catalyst blended diesel fuels

Abstract

ABSTRACT In this study various hybrid nanofluids were synthesized and investigated to evaluate the different thermophysical and heat transfer properties of nanoparticle suspension-based diesel fuel (DF). The experiments were performed to measure the thermophysical properties of several hybrid nanofluids containing nanoparticles of CuO-Al2O3, Gr-Al2O3 and CuO-Gr with surfactant Sodium Dodecyl Sulphate (SDS). Five nanofluids were synthesized at 5, 44, 102, 160 and 200 mg/l with 1-3% of SDS. The experimental results indicate significant improvements in heat transfer properties with the use of CuO-Al2O3, Gr-Al2O3 and CuO-Gr based nanodiesel test fuels compared to conventional diesel fuel. The thermal conductivity improved by 16.2%-29.5% while specific heat decreased by 3.5% -5.5%. The addition of a surfactant efficiently reduces the increase in viscosity which rises with nanoparticle concentration by 10%-17.5% respectively. Increased heat transport capacities are indicated by an 7-11% rise in the Nusselt number at the different mass concentrations. CuO-Gr hybrid nano-diesel shows encouragingly better results in thermal study that had the most significant modifications. This particular combination is the most promising for heat transfer applications because the heat transfer coefficient also significantly improves by 14-18% at a Reynolds number of 5474. Prandtl number of the CuO-Gr nano-diesel interestingly drops by 5.5%.