Effect of regulated harmful matters from a heavy-duty diesel engine by H2/O2 addition to the combustion chamber

This work investigated the effects of induction of hydrogen and oxygen mixture (H2/O2) to a heavy-duty diesel engine (HDDE) on the thermal performance, fuel consumption and emission characteristics. The HDDE was tested at one low load steady-state condition, 24.5% of the max load (40 km/h), using neat diesel and seven H2/O2 mixtures: 10–70 L/min, interval 10 L/min. The results show that brake thermal efficiency is increased from 31.1% for neat diesel to 39.9% for 70 L/min of H2/O2 mixture. For 10–40 L/min of H2/O2 mixture addition, the brake specific fuel consumption (BSFC) was higher than that of neat diesel. However, for 50, 60 and 70 L/min of H2/O2 mixture addition, the BSFC was lower than that of neat diesel by about 3.2%, 9.9% and 10.5%, respectively. Due to improved combustion efficiency, the emission concentrations of hydrocarbon, carbon dioxide and carbon monoxide were all lowered, while those of the nitrogen oxides were increased.