Effect of FIPs strategy and nanoparticles additives into the renewable fuel blends on NOX emissions, PM size distribution and soot oxidation in CRDI diesel engine

‏ The search of next prospective source of fuel is highlighted by the research community to compensate the aspects of shortcomings of diesel fuel and to treat the harmful emissions in the transportation sector. Among numerous economic sectors, the use of petro-diesel still the main fuel using for driving heavy machinery despite the high advance in electric motors for transportation systems. The characteristics of engine performance, nitrogen oxide (NOX) emissions, size distribution of particulate matter (PM), number and oxidation reactivity of soot particles from the effects of low and high fuel injection pressures (FIPs) and adding two types of nanoparticles (Al2O3 and TiO2) to the M20B10 blend (20 % of microalgae biodiesel, 10 % n-butanol and 70 % of diesel) were studied in common-rail diesel engine at different loads. The results revealed that the adding Al2O3 and TiO2 to the M20B10 blend decreased the BSFC by 21.28 % and 22.84 %, respectively, and also improved BTE by 4.46 % and 2.35 %, respectively, for different engine loads. It is observed that the applied HFIP and M20B10+Al2O3 blend also enhance the fuel consumption by 21.28 % and increase BTE by 9.63 % in comparison with M20B10+ TiO2 blend. In contrast, the presence HFIP with nano blends increased the NOX emissions by 24.73 % with respect to the LFIP, meanwhile the NOX emissions decreased from nano blends combustion more than to the neat M20B10 blend. The combustion of M20B10+Al2O3 blend decreased the PM concentration (by 52.82 %) and number (by 33.62 %) and when compared with blend of M20B10+ TiO2 and neat M20B10 blend combustion at HFIP. Furthermore, the reactivity of soot oxidation significantly increased when adding Al2O3 into the M20B10 blend and applying HFIP compared to the M20B10+ TiO2 blend.