Evaluate the effect of biodiesel and EGR system on diesel engine emissions

Vehicle Emission is one of the main causes of environmental damage. Vehicle engines produce carbon dioxide (CO2), hydrocarbon (HC), Nitrogen oxides (NOx) and many other harmful substances. An investigation was conducted using a compression-ignition engine fuelled with different ratios of blends of diesel and biodiesel at different EGR rates. The effects of different ratios of fuel blends and EGR rate on the emission characteristics (unburned hydrocarbon (HC), nitric oxide (NO), carbon dioxide (CO2) and oxygen (O2) were examined. The air-fuel equivalence ratio (λ), oil temperature and intake gas temperature were also analyzed. Results show that the different ratios of blends of diesel and biodiesel decrease HC emissions compared to those of the diesel fuel. The addition of biodiesel can increase NO, CO2 and O2 emissions compared with that of the diesel. EGR can reduce NO emissions in a compression-ignition engine fueled with diesel and biodiesel blends. The results also indicate that fuel consumption and air-fuel equivalence ratio were decreased by 19.2% and 72.9%, respectively, for 20% biodiesel blend with 20% EGR compared to diesel fuel without EGR. Intake gas temperature and oil temperature were also observed to increase by 87.5% and 6.2%, respectively, for 20% biodiesel blend with 20% EGR compared to diesel fuel without EGR.