Abstract
Oxygen-enriched combustion technology is an appealing option for enhancing the combustion process with reduced exhaust emissions in diesel engines. A study was conducted on a four-stroke single cylinder diesel engine to investigate how the combustion characteristics, exhaust emissions and performance are affected by oxygen-enriched air during partial and full load operating conditions. Specifically, the study focused on analyzing the impact on diesel combustion when the intake air was enriched with 10%, 15% and 20% of oxygen by conventional berating engine air flow rate. Results from the experiments demonstrated that an oxygen-enriched diesel engine resulted in improved combustion characteristics as enhancing the oxygen in the intake charge led to elevated peak cylinder pressure, rate of pressure rise and faster burn rates. The improved combustion process is resulting in a maximum of 13% additional cumulative heat release, 5% to 9% increase in thermal efficiency and an average of 12% decrease in brake-specific fuel consumption. A significant reduction in unburned hydrocarbon, carbon monoxide is noted, nevertheless presence of extra oxygen and elevated combustion temperature are yielding a notable increase in nitrogen oxide emissions.
Keywords: Brake-Specific Fuel Consumption, Brake Thermal Efficiency, Exhaust Emissions, Oxygen-Enriched Diesel Combustion, Performance.