Experimental study on the effects of graphene oxide nanoparticle added biodiesel–diesel fuel blends on engine performance and emissions

In this study, the effects of graphene oxide (GO) nanoparticle-added B20 biodiesel fuel on combustion characteristics, exhaust emissions, and fuel consumption of a single-cylinder diesel engine were experimentally investigated. The experiments were conducted under different engine load conditions using base diesel fuel as a reference and GO concentrations of 25, 50, 75, and 100 ppm. The results revealed that the addition of GO nanoparticles enhanced the combustion process, resulting in an increase of approximately 3–8% in the maximum in-cylinder pressure compared to base diesel fuel. Significant reductions in carbon monoxide (CO) and smoke opacity emissions were observed, ranging between 15–30% and 20–35%, respectively. Hydrocarbon (HC) emissions decreased at higher nanoparticle concentrations. However, nitrogen oxides (NOx) emissions showed a moderate increase (5–10%) due to elevated in-cylinder temperatures associated with improved combustion. Fuel consumption analysis demonstrated that GO addition partially compensated for the lower calorific value of biodiesel. The 100 ppm GO-added B20 fuel exhibited a 4–7% improvement in specific fuel consumption (SFC). Overall, the findings indicate that GO nanoparticle-enhanced biodiesel blends demonstrate strong potential as alternative fuels for diesel engines in terms of combustion efficiency and emission reduction when optimal nanoparticle concentrations are selected.