Reaction Mechanism of the Nitrogen-Enriched Air Combustion and Emission in Diesel Engine

Combustion intermediate products in nitrogen-enriched intake air (NEA), such as CH2O and H2O2, are researched in this paper with chemical reaction kinetics software. Besides that, combustion of n-Heptane in NEA, different intake temperature and different rotate speed are researched. Nitrogen-enriched air combustion process in diesel engine is simulated with CAE software. The maximum temperature and NOx emission at NEA and different rotate speed are studied in this paper. The increment of nitrogen in the intake air greatly impacts on the n-Heptane combustion intermediate products CH2O and H2O2; and the results show that the nitrogen is of fire-retardant properties. The temperature peak decrease with the increment of nitrogen in intake air. NOx emissions decrease with the increment of nitrogen in intake air.