Experimental investigations for rheological characteristics of TiO₂ nanoparticles doped diesel, biodiesel fuel blends for use in compression ignition engine

The present experimental study aims to investigate the variations in rheological characteristics of TiO₂ nanoparticles doped biodiesel diesel fuel blends at different temperatures and nanoparticle mass fractions. Fuel blends of Acacia Concinna biodiesel (AC BD) in the volume fraction of 40% are mixed with in the remaining 60% volume fraction of mineral diesel. Fuel blends are modified by doping TiO₂ nanoparticles in the weight fraction of 0.1, 0.2, 0.3 and 0.4 g/liter in biodiesel diesel fuel blends. These modified fuel blends (MNF) are prepared by means of mechanical stirring and ultra-sonication process, which are tested on Rheometer in a temperature range of 293K-363K under different shear rates. The experimental results showed that at concentration of 0.4 g/liter the viscosity of modified fuel blend (MNF0.4) was 7.16% more than the viscosity of mineral diesel. This increase in viscosity of MNF fuel blends are undesirable due to the fact that high injection pressure is required for proper atomization and combustion of fuel, which otherwise overshadows the gain in total heat release rate due to high heat of combustion of TiO2 nanoparticles. Furthermore, rheological characteristics of nanoparticle mixed modified fuel blends are found to be non- Newtonian and shear thinning. The findings of present study ascertain us that modified fuel blend up to 0.2 g/liter of TiO2 nanoparticle concentration (MNF0.2) in AC can be used as alternative fuel without much modifications in the operating and design parameters of existing diesel engine.