Abstract
The effect of O_2 concentration on production process of NOx and soot in diesel spray combustion in a high temperature and high pressure combustion vessel was experimentally examined. The O_2 concentration was changed from 5 to 21%. The ambient temperature was changed from 885K to 985K. The mode of non-luminous combustion like homogeneous-charge-combustion appeared before diffusion combustion under a low O_2 concentration condition. The flame temperature, the amount of soot and NOx decrease with the decrease of O_2 concentration. CO emission increase with the decrease of O_2 concentration condition.
