Influence of dispersant added nanoparticle additives with diesel-biodiesel blend on direct injection compression ignition engine: Combustion, engine performance, and exhaust emissions approach

The present work is intended to improve the performance of a direct injection compression-ignition engine fuelled with nanoparticle dispersed Flaxseed oil biodiesel blend (B20). The Chromium oxide (Cr2O3) nanoparticle additive with dispersant (QPAN 80) was mixed to B20 in concentrations of 50, 75, and 100 ppm. Tests were performed to assess the engine operating characteristics under varying load conditions such as 25, 50, 75, and 100% by maintaining a uniform speed of 1500 rpm. The combustion characteristics namely cylinder pressure (CP) and net heat release rate (NHRR) have greatly improved with the nanoparticle dispersed fuel than diesel-biodiesel blends. Besides, the brake thermal efficiency (BTE) has enhanced together with lower brake specific fuel consumption (BSFC). Finally, a significant decrease in emissions like carbon monoxide (CO), unburnt hydrocarbons (UHC), smoke, and nitrogen oxides (NOx) were observed. At maximum load, the CP and NHRR have improved by 18.66% and 11.61% respectively for B20Cr2O375DS1 (B20 with 75 ppm Cr2O3 and 1:1 dispersant) while the BTE has enhanced by 3.62% and the BSFC reduced by 3.53% compared to normal diesel. The reduction in CO, UHC, NOx, and smoke were found to be 14.05%, 12.93%, 6.66%, and 22.4% respectively for B20Cr2O375DS1 than conventional diesel. •Good stability was caused for B20 with surface modified Cr2O3 nanoparticles.•BTE was improved by 3.62% while the BSFC was lowered by 3.53% for B20Cr2O375DS1.•Enhancement of CP and NHRR for B20Cr2O375DS1were seen by18.66% and 11.61%.•Lower emissions were noticed together with NOx for B20Cr2O375DS1.