TY - JOUR
T1 - Diesel combustion analysis based on two-zone model
T2 - (Examination of excess air ratio in burned zone)
AU - Ishida, Masahiro
AU - Ueki, Hironobu
AU - Matsumura, Noboru
AU - Chen, Zhi Li
PY - 1996/8
Y1 - 1996/8
N2 - The burned zone excess air ratio λd in the diffusion combustion process was analyzed using the two-zone model, and it was compared with the excess air ratio λf estimated using a steady diffusion flame model of the fuel spray. It is found that λd is dependent on the fuel spray penetration and ignition delay. If the premixed combustion fraction is less than 50%, the NO formation is minimally influenced by the excess air ratio during premixed combustion and is dependent on the excess air ratio λd which determines the maximum temperature during diffusion combustion. It is clarified by analysis of the two-zone model that the large reduction in NOx due to timing retard is mainly caused by decreases in both combustion temperature and combustion pressure, and the small reduction in NOx occurring when the nozzle-hole diameter is decreased, is due to a small decrease in combustion pressure resulting from a decrease in the heat release rate during premixed combustion.
AB - The burned zone excess air ratio λd in the diffusion combustion process was analyzed using the two-zone model, and it was compared with the excess air ratio λf estimated using a steady diffusion flame model of the fuel spray. It is found that λd is dependent on the fuel spray penetration and ignition delay. If the premixed combustion fraction is less than 50%, the NO formation is minimally influenced by the excess air ratio during premixed combustion and is dependent on the excess air ratio λd which determines the maximum temperature during diffusion combustion. It is clarified by analysis of the two-zone model that the large reduction in NOx due to timing retard is mainly caused by decreases in both combustion temperature and combustion pressure, and the small reduction in NOx occurring when the nozzle-hole diameter is decreased, is due to a small decrease in combustion pressure resulting from a decrease in the heat release rate during premixed combustion.
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U2 - 10.1299/jsmeb.39.632
DO - 10.1299/jsmeb.39.632
M3 - Article
AN - SCOPUS:0030211727
SN - 0914-8817
VL - 39
SP - 632
EP - 639
JO - JSME International Journal, Series B: Fluids and Thermal Engineering
JF - JSME International Journal, Series B: Fluids and Thermal Engineering
IS - 3
ER -